Internet Engineering Task Force Alan Johnston
Internet Draft WorldCom
Document: draft-ietf-sipping-call-flows-01.txt Steve Donovan
Category: Informational Robert Sparks
July 2002 Chris Cunningham
Expires: December 2002 Dean Willis
Jonathan Rosenberg
dynamicsoft
Kevin Summers
Sonus
Henning Schulzrinne
Columbia University
Session Initiation Protocol Call Flow Examples
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of RFC2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that other
groups may also distribute working documents as Internet-Drafts.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet- Drafts as reference
material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html.
Abstract
This informational document gives examples of Session Initiation
Protocol (SIP) call flows. Elements in these call flows include SIP
User Agents and Clients, SIP Proxy and Redirect Servers, and Gateways
to the PSTN (Public Switch Telephone Network). Scenarios include SIP
Registration, SIP to SIP calling, SIP to Gateway, Gateway to SIP, and
Gateway to Gateway via SIP. Call flow diagrams and message details
are shown. PSTN telephony protocols are illustrated using ISDN
(Integrated Services Digital Network), ANSI ISUP (ISDN User Part),
and FGB (Feature Group B) circuit associated signaling. PSTN calls
are illustrated using global telephone numbers from the PSTN and
private extensions served on by a PBX (Private Branch Exchange).
Example SIP messages used for testing during SIP interoperability
test events include SIP "torture test" messages, and messages with
invalid parameters, methods, and tags.
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Internet Draft SIP Call Flow Examples July 2002
Table of Contents
1 Overview...................................................4
1.1 General Assumptions........................................4
1.2 Legend for Message Flows...................................5
1.3 SIP Protocol Assumptions...................................6
2 SIP Registration...........................................7
2.1 Success Scenarios..........................................7
2.1.1 SIP Client New Registration................................7
2.1.2 User updates contact list..................................9
2.1.3 User Requests Current Contact List........................11
2.1.4 User Cancels Registration.................................12
2.2 Failure Scenarios.........................................13
2.2.1 Unsuccessful SIP registration.............................13
3 SIP to SIP Dialing........................................15
3.1 Success Scenarios.........................................15
3.1.1 Successful Simple SIP to SIP..............................16
3.1.2 Successful SIP to SIP through two proxies.................19
3.1.3 Successful SIP to SIP with Multi Proxy Authentication.....29
3.1.4 Successful SIP to SIP with Proxy failure..................39
3.1.5 Successful SIP to SIP through SIP ALG ....................47
3.1.6 Successful SIP to SIP via Redirect and Proxy SDP in ACK...55
3.1.7 Successful SIP to SIP with re-INVITE......................61
3.2 Failure Scenarios.........................................67
3.2.1 Unsuccessful SIP to SIP no answer.........................67
3.2.2 Unsuccessful SIP to SIP busy..............................74
3.2.3 Unsuccessful SIP to SIP no response.......................79
3.2.4 Unsuccessful SIP to SIP Temporarily Unavailable...........84
4 SIP to Gateway Dialing....................................90
4.1 Success Scenarios.........................................90
4.1.1 Successful SIP to ISUP PSTN call..........................91
4.1.2 Successful SIP to ISDN PBX call...........................99
4.1.3 Successful SIP to ISUP PSTN call with overflow...........107
4.2 Failure Scenarios........................................115
4.2.1 Unsuccessful SIP to PSTN call: Treatment from PSTN.......116
4.2.2 Unsuccessful SIP to PSTN: REL w/Cause from PSTN..........123
4.2.3 Unsuccessful SIP to PSTN: ANM Timeout....................127
5 Gateway to SIP Dialing...................................133
5.1 Success Scenarios........................................133
5.1.1 Successful PSTN to SIP call..............................134
5.1.2 Successful PSTN to SIP call, Fast Answer.................140
5.1.3 Successful PBX to SIP call...............................145
5.2 Failure Scenarios........................................151
5.2.1 Unsuccessful PSTN to SIP REL, SIP error mapped to REL....151
5.2.2 Unsuccessful PSTN to SIP REL, SIP busy mapped to REL.....153
5.2.3 Unsuccessful PSTN->SIP, SIP error interworking to tones..157
5.2.4 Unsuccessful PSTN->SIP, ACM timeout......................161
5.2.5 Unsuccessful PSTN->SIP, ACM timeout, stateless Proxy.....165
5.2.6 Unsuccessful PSTN->SIP, Call Abandonment.................168
6 Gateway to Gateway Dialing via SIP Network...............174
6.1 Success Scenarios........................................174
6.1.1 Successful ISUP PSTN to ISUP PSTN call...................175
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6.1.2 Successful FGB PBX to ISDN PBX call with overflow........182
7 SIP Test Messages........................................191
7.1 INVITE Parser Torture Test Message.......................191
7.2 INVITE with Proxy-Require and Require....................192
7.3 INVITE with Unknown Schemes in URIs and URLs.............192
7.4 REGISTER with Y2038 Test.................................193
7.5 INVITE with inconsistent Accept and message body.........193
7.6 INVITE with non-SDP message body.........................194
7.7 Unknown Method Message...................................194
7.8 Unknown Method with CSeq Error...........................195
7.9 REGISTER with Unknown Authorization Scheme...............195
7.10 Multiple SIP Request in a Single Message.................196
7.11 INVITE missing Required Headers..........................197
7.12 INVITE with Duplicate Required Headers...................197
7.13 INVITE with Illegal Expires Header.......................198
7.14 200 OK Response with Broadcast Via Header................198
7.15 INVITE with Invalid Via and Contact Headers..............199
7.16 INVITE with Incorrect Content-Length Header..............200
7.17 INVITE with Invalid Value for Content-Length.............200
7.18 INVITE with Garbage after Message Body...................201
7.19 INVITE with Error in Display Name in To Header...........201
7.20 INVITE with long tokens, Call-ID, and SIP URIs...........202
7.21 INVITE with Illegal Enclosing of Request-URI in "<>".....202
7.22 INVITE with Illegal LWS within Elements of Request-URI...203
7.23 INVITE with Illegal >1 SP between elements Request-URI...204
7.24 INVITE with a Legal SIP URI With Escaped Characters......204
7.25 INVITE with the Illegal Escaped Headers Request-URI......205
7.26 INVITE with Unknown Scheme in Request-URI................206
7.27 OPTIONS with no LWS between display name and "<".........206
7.28 OPTIONS with Extra WS between display name and "<".......206
7.29 INVITE with an Illegal Date Format.......................207
7.30 INVITE with Passed Expires Time..........................207
7.31 INVITE with Max-Forwards Set to Zero.....................208
7.32 REGISTER with Escaped Header in a Legal Contact URI......209
7.33 REGISTER with Escaped Header in an Illegal Contact URI...209
7.34 INVITE with Long Values in Headers.......................210
7.35 OPTIONS with Multiple Headers............................211
7.36 INVITE with Large Number of SDP Attributes and Long URI..211
7.37 REGISTER with Contact Parameter..........................212
7.38 REGISTER with a URI Parameter............................213
7.39 INVITE with Unquoted Display Name with Tokens............213
7.40 INVITE with Unquoted Display Name with Non-Token Chars...213
7.41 INVITE with Unknown (Higher) Protocol Version Start Line.214
8 Security Considerations .................................214
9 IANA Considerations .....................................215
10 Acknowledgements.........................................215
11 References...............................................215
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1 Overview
The call flows shown in this document were developed in the design of
a carrier-class SIP IP Telephony network. They represent an example
minimum set of functionality for SIP to be used in IP Telephony
applications. The message examples were developed during the SIP
interoperability tests known as SIPit.
It is the hope of the authors that this document will be useful for
SIP implementors, designers, and protocol researchers alike and will
help further the goal of a standard SIP implementation for IP
Telephony. It is envisioned that as changes to the standard and
additional RFCs are added that this document will reflect those
changes and represent the current state of a standard interoperable
SIP IP Telephony implementation.
Note that this document is informational, and is NOT NORMATIVE on any
aspect of SIP or SIP/PSTN interworking.
These call flows are based on the current version 2.0 of SIP in
[RFC3261] with SDP usage described in [RFC3264].
Various PSTN signaling protocols are illustrated in this document:
ISDN (Integrated Services Digital Network), ANSI ISUP (ISDN User
Part) and FGB (Feature Group B) circuit associated signaling. They
were chosen to illustrate the nature of SIP/PSTN interworking - they
are not a complete or even representative set. Also, some details
and parameters of these PSTN protocols have been omitted. For full
information about SIP to ISUP mapping, refer to [SIP-ISUP].
Finally, some example messages are given along with expected
behavior of clients and servers.
1.1 General Assumptions
A number of architecture, network, and protocol assumptions underly
the call flows in this document. Note that these assumptions are not
requirements. They are outlined in this section so that they may be
taken into consideration and to aid in the understanding of the call
flow examples.
The authentication of SIP User Agents in these example call flows is
performed using SIP Digest as defined in [RFC3261] and [RFC2617].
Throughout this document the call flows show a network where the
proxy servers authenticate users on behalf of gateways. Gateways may
also authenticate users directly. Both of these are reasonable usages
of SIP. If gateways do not authenticate directly they would be to
refuse requests from entities other than trusted proxy servers with
which they have effective channel security (for example [RFC2246] or
[RFC2401])."
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The SIP Proxy Server has access to a Location Service and other
databases. Information present in the Request-URI and the context
(From header) is sufficient to determine to which proxy or gateway
the message should be routed. In most cases, a primary and secondary
route will be determined in case of Proxy or Gateway failure
downstream.
Some Proxy Servers in these call flows insert Record-Route headers
into requests to ensure that they are in the signaling path for
future message exchanges.
Gateways provide tones (ringing, busy, etc) and announcements to the
PSTN side based on SIP response messages, or pass along audio in-band
tones (ringing, busy tone, etc.) in an early media stream to the SIP
side.
The interactions between the Proxy and Gateway can be summarized as
follows:
. The SIP Proxy Server performs digit analysis and lookup and
locates the correct gateway.
. The SIP Proxy Server performs gateway location based on primary
and secondary routing.
Telephone numbers are usually represented as SIP URIs. Note that an
alternative is the use of the tel URI [RFC2806].
These flows show UDP for transport. Other transport schemes could
also be used.
1.2 Legend for Message Flows
Dashed lines (---) represent signaling messages that are mandatory to
the call scenario. These messages can be SIP or PSTN
signaling. The arrow indicates the direction of message flow.
Double dashed lines (===) represent media paths between network
elements.
Messages with parentheses around their name represent optional
messages.
Messages are identified in the Figures as F1, F2, etc. This
references the message details in the list that follows the Figure.
Comments in the message details are shown in the following form:
/* Comments. */
1.3 SIP Protocol Assumptions
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This document is informational only and is NOT NORMATIVE in any
sense.
For simplicity in reading and editing the document, there are a
number of differences between some of the examples and actual SIP
messages. For example, the SIP Digest responses are not actual MD5
encodings. Call-IDs are often repeated, and CSeq counts often begin
at 1. Header fields are usually shown in the same order. Usually
only the minimum required header field set is shown, others that
would normally be present such as Accept, Supported, Allow, etc are
not shown.
Actors:
Element Display Name URI IP Address
------- ------------ --- ----------
User Agent BigGuy UserA@atlanta.com 192.168.100.101
User Agent LittleGuy UserB@biloxi.com 192.168.200.201
User Agent UserB@chicago.com 192.168.200.100
Proxy Server ss1.atlanta.com 192.168.255.111
Proxy/Registrar ss2.biloxi.com 192.168.156.222
Proxy Server ss3.chicago.com 192.168.182.333
ALG alg1.atlanta.com 192.168.255.128
User Agent (Gateway) gw1.atlanta.com 192.168.255.201
User Agent (Gateway) gw2.atlanta.com 192.168.255.202
User Agent (Gateway) gw3.atlanta.com 192.168.255.203
User Agent (Gateway) ngw1.atlanta.com 192.168.255.101
User Agent (Gateway) ngw2.atlanta.com 192.168.255.102
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2 SIP Registration
2.1 Success Scenarios
Registration binds a particular device Contact URI with a SIP user
AOR (Address of Record).
2.1.1 SIP Client New Registration
User B SIP Server
| |
| REGISTER F1 |
|------------------------------>|
| 401 Unauthorized F2 |
|<------------------------------|
| REGISTER F3 |
|------------------------------>|
| 200 OK F4 |
|<------------------------------|
| |
User B sends a SIP REGISTER request to the SIP server. The request
includes the user's contact list. The SIP server provides a
challenge to User B. User B enters her/his valid user ID and
password. User B's SIP client encrypts the user information
according to the challenge issued by the SIP server and
sends the response to the SIP server. The SIP server validates the
user's credentials. It registers the user in its contact database
and returns a response (200 OK) to User B's SIP client. The response
includes the user's current contact list in Contact headers. The
format of the authentication shown is SIP digest. It is assumed that
User B has not previously registered with this Server.
Message Details
F1 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F2 401 Unauthorized SIP Server -> User B
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SIP/2.0 401 Unauthorized
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>;tag=1410948204
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
WWW-Authenticate: Digest realm="atlanta.com", qop="auth",
nonce="ea9c8e88df84f1cec4341ae6cbe5a359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F3 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=ja743ks76zlflH
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 2 REGISTER
Contact: <sip:UserB@192.168.200.201>
Authorization: Digest username="UserB", realm="atlanta.com"
nonce="ea9c8e88df84f1cec4341ae6cbe5a359", opaque="",
uri="sip:ss2.biloxi.com", response="dfe56131d1958046689d83306477ecc"
Content-Length: 0
F4 200 OK SIP Server -> B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=ja743ks76zlflH
To: LittleGuy <sip:UserB@biloxi.com>;tag=37GkEhwl6
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 2 REGISTER
Contact: <sip:UserB@192.168.200.201>;expires=3600
Content-Length: 0
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2.1.2 User updates contact list
User B SIP Server
| |
| REGISTER F1 |
|------------------------------>|
| 200 OK F2 |
|<------------------------------|
| |
User B wishes to update the list of addresses where the SIP server
will redirect or forward INVITE requests.
User B sends a SIP REGISTER request to the SIP server. User B's
request includes an updated contact list. Since the user already has
authenticated with the server, the user supplies authentication
credentials with the request and is not challenged by the server.
The SIP server validates the user's credentials. It registers the
user in its contact database, updates the user's contact list, and
returns a response (200 OK) to User B's SIP client. The response
includes the user's current contact list in Contact headers.
Message Details
F1 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Contact: mailto:UserB@biloxi.com
Authorization: Digest username="UserB", realm="atlanta.com",
qop="auth", nonce="1cec4341ae6cbe5a359ea9c8e88df84f", opaque="",
uri="sip:ss2.biloxi.com",
response="71ba27c64bd01de719686aa4590d5824"
Content-Length: 0
F2 200 OK SIP Server -> B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>;tag=34095828jh
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
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CSeq: 1 REGISTER
Contact: <sip:UserB@192.168.200.201>;expires=3600
Contact: <mailto:UserB@biloxi.com>;expires=4294967295
Content-Length: 0
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2.1.3 User Requests Current Contact List
User B SIP Server
| |
| REGISTER F1 |
|------------------------------>|
| 200 OK F2 |
|<------------------------------|
| |
User B sends a register request to the Proxy Server containing no
Contact headers, indicating the user wishes to query the server for
the user's current contact list. Since the user already has
authenticated with the server, the user supplies authentication
credentials with the request and is not challenged by the server. The
SIP server validates the user's credentials. The server returns a
response (200 OK) which includes the user's current registration list
in Contact headers.
Message Details
F1 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Authorization: Digest username="UserB", realm="atlanta.com",
nonce="df84f1cec4341ae6cbe5ap359a9c8e88", opaque="",
uri="sip:ss2.biloxi.com",
response="aa7ab4678258377c6f7d4be6087e2f60"
Content-Length: 0
F2 200 OK SIP Server -> B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>;tag=jqoiweu75
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Contact: <sip:UserB@192.168.200.201>;expires=3600
Contact: <mailto:UserB@biloxi.com>;expires=4294967295
Content-Length: 0
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2.1.4 User Cancels Registration
User B SIP Server
| |
| REGISTER F1 |
|------------------------------>|
| 200 OK F2 |
|<------------------------------|
| |
User B wishes to cancel their registration with the SIP
server. User B sends a SIP REGISTER request to the
SIP server. The request has an expiration period of 0 and applies to
all existing contact locations. Since the user already has
authenticated with the server, the user supplies authentication
credentials with the request and is not challenged by the server.
The SIP server validates the user's credentials. It clears the
user's contact list, and returns a response (200 OK) to User B's SIP
client.
Message Details
F1 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Expires: 0
Contact: *
Authorization: Digest username="UserB", realm="atlanta.com",
nonce="88df84f1cac4341aea9c8ee6cbe5a359", opaque="",
uri="sip:ss2.biloxi.com",
response="ff0437c51696f9a76244f0cf1dbabbea"
Content-Length: 0
F2 200 OK SIP Server -> B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>;tag=1418nmdsrf
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Content-Length: 0
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2.2 Failure Scenarios
2.2.1 Unsuccessful SIP registration
User B SIP Server
| |
| REGISTER F1 |
|------------------------------>|
| 401 Unauthorized F2 |
|<------------------------------|
| REGISTER F3 |
|------------------------------>|
| 401 Unauthorized F4 |
|<------------------------------|
| |
User B sends a SIP REGISTER request to the SIP Server. The SIP
server provides a challenge to User B. User B enters her/his user ID
and password. User B's SIP client encrypts the user information
according to the challenge issued by the SIP server and sends the
response to the SIP server. The SIP server attempts to validate the
user's credentials, but they are not valid (the user's password does
not match the password established for the user's account). The
server returns a response (401 Unauthorized) to User B's SIP client.
Message Details
F1 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F2 Unauthorized SIP Server -> User B
SIP/2.0 401 Unauthorized
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=a73kszlfl
To: LittleGuy <sip:UserB@biloxi.com>;tag=1410948204
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Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 1 REGISTER
WWW-Authenticate: Digest realm="atlanta.com", qop="auth",
nonce="f1cec4341ae6ca9c8e88df84be55a359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F3 REGISTER B -> SIP Server
REGISTER sip:ss2.biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=JueHGuidj28dfga
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 2 REGISTER
Contact: <sip:UserB@192.168.200.201>
Authorization: Digest username="UserB", realm="atlanta.com",
nonce="f1cec4341ae6ca9c8e88df84be55a359", opaque="",
uri="sip:ss2.biloxi.com",
response="61f8470ceb87d7ebf508220214ed438b"
Content-Length: 0
/* The response above encodes the incorrect password */
F4 401 Unauthorized SIP Server -> User B
SIP/2.0 401 Unauthorized
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=JueHGuidj28dfga
To: LittleGuy <sip:UserB@biloxi.com>;tag=1410948204
Call-ID: 1j9FpLxk3uxtm8tn@biloxi.com
CSeq: 2 REGISTER
WWW-Authenticate: Digest realm="atlanta.com", qop="auth",
nonce="84f1c1ae6cbe5ua9c8e88dfa3ecm3459",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
Johnston, et al. Informational [Page 14]
Internet Draft SIP Call Flow Examples July 2002
3 SIP to SIP Dialing
3.1 Success Scenarios
This section details calls between two SIP User Agents (UAs):
User A and User B. User A (LittleGuy sip:UserA@atlanta.com) and User
B (BigGuy sip:UserB@biloxi.com) are assumed to be SIP phones or SIP-
enabled devices. The successful calls show the initial signaling,
the exchange of media information in the form of SDP payloads, the
establishment of the media session, then finally the termination of
the call.
SIP digest authentication is used by Proxy Servers to
authenticate the caller User A. It is assumed that User B has
registered with Proxy Server Proxy 2 as per Section 2.1 to be able to
receive the calls via the Proxy.
Johnston, et al. Informational [Page 15]
Internet Draft SIP Call Flow Examples July 2002
3.1.1 Successful Simple SIP to SIP
User A User B
| |
| INVITE F1 |
|----------------------->|
| 180 Ringing F2 |
|<-----------------------|
| |
| 200 OK F3 |
|<-----------------------|
| ACK F4 |
|----------------------->|
| Both Way RTP Media |
|<======================>|
| |
| BYE F5 |
|<-----------------------|
| 200 OK F6 |
|----------------------->|
| |
In this scenario, User A completes a call to User B directly.
Message Details
F1 INVITE User A -> User B
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 180 Ringing User B -> User A
Johnston, et al. Informational [Page 16]
Internet Draft SIP Call Flow Examples July 2002
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=8321234356
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F3 200 OK User B -> User A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=8321234356
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 ACK User A -> User B
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=8321234356
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* RTP streams are established between A and B */
/* User B Hangs Up with User A. Note that the CSeq is NOT 2, since
User A and User B maintain their own independent CSeq counts.
(The INVITE was request 1 generated by User A, and the BYE is
request 1 generated by User B) */
F5 BYE User B -> User A
Johnston, et al. Informational [Page 17]
Internet Draft SIP Call Flow Examples July 2002
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=8321234356
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F6 200 OK User A -> User B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=8321234356
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
Johnston, et al. Informational [Page 18]
Internet Draft SIP Call Flow Examples July 2002
3.1.2 Successful SIP to SIP through two proxies
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| | |
| 407 F2 | | |
|<---------------| | |
| ACK F3 | | |
|--------------->| | |
| INVITE F4 | | |
|--------------->| INVITE F5 | |
| 100 F6 |--------------->| INVITE F7 |
|<---------------| 100 F8 |--------------->|
| |<---------------| |
| | | 180 F9 |
| | 180 F10 |<---------------|
| 180 F11 |<---------------| |
|<---------------| | 200 F12 |
| | 200 F13 |<---------------|
| 200 F14 |<---------------| |
|<---------------| | |
| ACK F15 | | |
|--------------->| ACK F16 | |
| |--------------->| ACK F17 |
| | |--------------->|
| Both Way RTP Media |
|<================================================>|
| | | BYE F18 |
| | BYE F19 |<---------------|
| BYE F20 |<---------------| |
|<---------------| | |
| 200 F21 | | |
|--------------->| 200 F22 | |
| |--------------->| 200 F23 |
| | |--------------->|
| | | |
In this scenario, User A completes a call to User B using two proxies
Proxy 1 and Proxy 2. The initial INVITE (F1) contains a pre-loaded
Route header with the address of Proxy 1 (Proxy 1 is configured as a
default outbound proxy for User A). The request does not contain the
Authorization credentials Proxy 1 requires, so a 407 Proxy
Authorization response is sent containing the challenge information.
A new INVITE (F4) is then sent containing the correct credentials and
the call proceeds. The call terminates when User B disconnects by
initiating a BYE message.
Proxy 1 inserts a Record-Route header into the INVITE message to
ensure that it is present in all subsequent message exchanges. Proxy
2 also inserts itself into the Record-Route header. The ACK (F15)
and BYE (F18) both have a Route header.
Johnston, et al. Informational [Page 19]
Internet Draft SIP Call Flow Examples July 2002
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 challenges User A for authentication */
F2 407 Proxy Authorization Required Proxy 1 -> User A
SIP/2.0 407 Proxy Authorization Required
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=3flal12sf
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 INVITE
Proxy-Authenticate: Digest realm="atlanta.com", qop="auth",
nonce="f84f1cec41e6cbe5aea9c8e88d359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F3 ACK A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=3flal12sf
Johnston, et al. Informational [Page 20]
Internet Draft SIP Call Flow Examples July 2002
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* User A responds be re-sending the INVITE with authentication
credentials in it. */
F4 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="wf84f1ceczx41ae6cbe5aea9c8e88d359", opaque="",
uri="sip:UserB@biloxi.com", response="42ce3cef44b22f50c6a6071bc8"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 accepts the credentials and forwards the INVITE to Proxy
2. Proxy 1 is assumed to have been authenticated by Proxy 2 using
IPSec. Client for A prepares to receive data on port 49172 from the
network. */
F5 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Johnston, et al. Informational [Page 21]
Internet Draft SIP Call Flow Examples July 2002
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F6 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Content-Length: 0
F7 INVITE Proxy 2 -> B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F8 100 Trying Proxy 2 -> Proxy 1
Johnston, et al. Informational [Page 22]
Internet Draft SIP Call Flow Examples July 2002
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Content-Length: 0
F9 180 Ringing B -> Proxy 2
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
Contact: <sip:UserB@192.168.200.201>
CSeq: 2 INVITE
Content-Length: 0
F10 180 Ringing Proxy 2 -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
Contact: <sip:UserB@192.168.200.201>
CSeq: 2 INVITE
Content-Length: 0
F11 180 Ringing Proxy 1 -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Johnston, et al. Informational [Page 23]
Internet Draft SIP Call Flow Examples July 2002
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
Contact: <sip:UserB@192.168.200.201>
CSeq: 2 INVITE
Content-Length: 0
F12 200 OK B -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F13 200 OK Proxy 2 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
Johnston, et al. Informational [Page 24]
Internet Draft SIP Call Flow Examples July 2002
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F14 200 OK Proxy 1 -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F15 ACK A -> Proxy 1
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>, <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 ACK
Content-Length: 0
F16 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Johnston, et al. Informational [Page 25]
Internet Draft SIP Call Flow Examples July 2002
Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 ACK
Content-Length: 0
F17 ACK Proxy 2 -> B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 3848276298220188511@atlanta.com
CSeq: 2 ACK
Content-Length: 0
/* RTP streams are established between A and B */
/* User B Hangs Up with User A. */
/* Again, note that the CSeq is NOT 3. User A and User B maintain
their own separate CSeq counts */
F18 BYE User B -> Proxy 2
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F19 BYE Proxy 2 -> Proxy 1
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
Max-Forwards: 69
Route: <sip:ss1.atlanta.com;lr>
Johnston, et al. Informational [Page 26]
Internet Draft SIP Call Flow Examples July 2002
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F20 BYE Proxy 1 -> User A
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
Max-Forwards: 68
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F21 200 OK User A -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F22 200 OK Proxy 1 -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.100.101
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
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F23 200 OK Proxy 2 -> User B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 3848276298220188511@atlanta.com
CSeq: 1 BYE
Content-Length: 0
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3.1.3 SIP to SIP with Multi Proxy Authentication
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|----------->| | |
| 407 Proxy Authorization Required F2 |
|<-----------| | |
| ACK F3 | | |
|----------->| | |
| INVITE F4 | | |
|----------->| | |
| 100 F5 | | |
|<-----------| INVITE F6 | |
| |---------->| |
| | 407 Proxy Authorization Required F7
| |<----------| |
| | ACK F8 | |
| |---------->| |
| 407 Proxy Authorization Required F9 |
|<-----------| | |
| ACK F10 | | |
|----------->| | |
| INVITE F11| | |
|----------->| | |
| 100 F12 | | |
|<-----------| INVITE F13| |
| |---------->| |
| | 100 F14 | |
| |<----------| INVITE F15 |
| | |------------>|
| | | 200 OK F16 |
| | 200 OK F17|<------------|
| 200 OK F18 |<----------| |
|<-----------| | |
| ACK F19 | | |
|----------->| ACK F20 | |
| |---------->| ACK F21 |
| | |------------>|
| RTP Media Path |
|<====================================>|
In this scenario, User A completes a call to User B using two proxies
Proxy 1 and Proxy 2. User A has valid credentials in both domains.
Since the initial INVITE (F1) does not contain the
Authorization credentials Proxy 1 requires, so a 407 Proxy
Authorization response is sent containing the challenge information.
A new INVITE (F4) is then sent containing the correct credentials and
the call proceeds after Proxy 2 challenges and receives valid
credentials. The call terminates when User B disconnects by
initiating a BYE message.
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Proxy 1 inserts a Record-Route header into the INVITE message to
ensure that it is present in all subsequent message exchanges. Proxy
2 also inserts itself into the Record-Route header.
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 challenges User A for authentication */
F2 407 Proxy Authorization Required Proxy 1 -> User A
SIP/2.0 407 Proxy Authorization Required
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=876321
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Proxy-Authenticate: Digest realm="atlanta.com", qop="auth",
nonce="wf84f1cczx41ae6cbeaea9ce88d359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F3 ACK A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
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Max-Forwards: 70
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=876321
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* User A responds be re-sending the INVITE with authentication
credentials in it. The same Call-ID is used, so the CSeq is
increased. */
F4 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="wf84f1ceczx41ae6cbe5aea9c8e88d359", opaque="",
uri="sip:UserB@biloxi.com", response="42ce3cef44b22f50c6a6071bc8"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 accepts the credentials and forwards the INVITE to Proxy
2. Proxy 1 is assumed to have been authenticated by Proxy 2 using
IPSec. Client for A prepares to receive data on port 49172 from the
network. */
F5 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
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CSeq: 2 INVITE
Content-Length: 0
F6 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 2 challenges User A for authentication */
F7 407 Proxy Authorization Required Proxy 2 -> Proxy 1
SIP/2.0 407 Proxy Authorization Required
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=838209
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Proxy-Authenticate: Digest realm="biloxi.com", qop="auth",
nonce="c1e22c41ae6cbe5ae983a9c8e88d359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F8 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
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Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=838209
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 ACK
Content-Length: 0
/* Proxy 1 forwards the challenge to User A for authentication from
Proxy 2 */
F9 407 Proxy Authorization Required Proxy 1 -> User A
SIP/2.0 407 Proxy Authorization Required
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=838209
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Proxy-Authenticate: Digest realm="biloxi.com", qop="auth",
nonce="c1e22c41ae6cbe5ae983a9c8e88d359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F10 ACK User A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=838209
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 ACK
Content-Length: 0
/* User A responds be re-sending the INVITE with authentication
credentials for Proxy 1 AND Proxy 2. */
F11 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
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nonce="wf84f1ceczx41ae6cbe5aea9c8e88d359", opaque="",
uri="sip:UserB@biloxi.com", response="42ce3cef44b22f50c6a6071bc8"
Proxy-Authorization: Digest username="UserA", realm="biloxi.com",
nonce="c1e22c41ae6cbe5ae983a9c8e88d359", opaque="",
uri="sip:UserB@biloxi.com", response="f44ab22f150c6a56071bce8"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 finds its credentials and authorizes User A, forwarding
the INVITE to Proxy. */
F12 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Content-Length: 0
F13 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="biloxi.com",
nonce="c1e22c41ae6cbe5ae983a9c8e88d359", opaque="",
uri="sip:UserB@biloxi.com", response="f44ab22f150c6a56071bce8"
Content-Type: application/sdp
Content-Length: 147
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v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 2 finds its credentials and authorizes User A, forwarding
the INVITE to User B. */
F14 100 Trying Proxy 2 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Content-Length: 0
F15 INVITE Proxy 2 -> User B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK31972.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
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/* User B answers the call immediately */
F16 200 OK User B -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK31972.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=9103874
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F17 200 OK Proxy 2 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=9103874
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
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a=rtpmap:0 PCMU/8000
F18 200 OK Proxy 1 -> User A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=9103874
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F19 ACK User A -> Proxy 1
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>, <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=9103874
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 ACK
Content-Length: 0
F20 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=9103874
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 ACK
Contact: <sip:UserB@192.168.200.201>
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Content-Length: 0
F21 ACK Proxy 2 -> User A
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK31972.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK230f2.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=9103874
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 ACK
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
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3.1.4 Successful SIP to SIP with Proxy failure
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| | |
| INVITE F2 | | |
|--------------->| | |
| INVITE F3 | | |
|--------------->| | |
| INVITE F4 | | |
|--------------->| | |
| INVITE F5 | | |
|--------------->| | |
| INVITE F6 | | |
|--------------->| | |
| INVITE F7 | | |
|--------------->| | |
| INVITE F8 | |
|-------------------------------->| |
| 407 F9 | |
|<--------------------------------| |
| ACK F10 | |
|-------------------------------->| |
| INVITE F11 | |
|-------------------------------->| INVITE F12 |
| 100 F13 |--------------->|
|<--------------------------------| |
| | 180 F14 |
| 180 F15 |<---------------|
|<--------------------------------| |
| | 200 F16 |
| 200 F17 |<---------------|
|<--------------------------------| |
| ACK F18 | |
|-------------------------------->| ACK F19 |
| |--------------->|
| Both Way RTP Media |
|<================================================>|
| | BYE F20 |
| BYE F21 |<---------------|
|<--------------------------------| |
| 200 F22 | |
|-------------------------------->| 200 F23 |
| |--------------->|
| | |
In this scenario, User A completes a call to User B via a Proxy
Server. User A is configured for a primary SIP Proxy Server Proxy 1
and a secondary SIP Proxy Server Proxy 2 (Or is able to use DNS SRV
records to locate Proxy 1 and Proxy 2). User A has valid credentials
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Internet Draft SIP Call Flow Examples July 2002
for both domains. Proxy 1 is out of service and does not respond to
INVITEs (it is reachable, but unresponsive). User A then completes
the call to User B using Proxy 2.
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK465bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 INVITE A -> Proxy 1
Same as Message F1
F3 INVITE A -> Proxy 1
Same as Message F1
F4 INVITE A -> Proxy 1
Same as Message F1
F5 INVITE A -> Proxy 1
Same as Message F1
F6 INVITE A -> Proxy 1
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Internet Draft SIP Call Flow Examples July 2002
Same as Message F1
F7 INVITE A -> Proxy 1
Same as Message F1
/* User A gives up on the unresponsive proxy */
F8 INVITE A -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 2 challenges User A for authentication */
F9 407 Proxy Authorization Required Proxy 2 -> User A
SIP/2.0 407 Proxy Authorization Required
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=2421452
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 INVITE
Proxy-Authenticate: Digest realm="biloxi.com", qop="auth",
nonce="1ae6cbe5ea9c8e8df84fqnlec434a359",
opaque="", stale=FALSE, algorithm=MD5
Content-Length: 0
F10 ACK A -> Proxy 2
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ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=2421452
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* User A responds be re-sending the INVITE with authentication
credentials in it. */
F11 INVITE A -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="biloxi.com",
nonce="1ae6cbe5ea9c8e8df84fqnlec434a359", opaque="",
uri="sip:UserB@biloxi.com",
response="8a880c919d1a52f20a1593e228adf599"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 2 accepts the credentials and forwards the INVITE to User B.
Client for A prepares to receive data on port 49172 from the network.
*/
F12 INVITE Proxy 2 -> B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss2.biloxi.com;lr>
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From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F13 100 Trying Proxy 2 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Content-Length: 0
F14 180 Ringing B -> Proxy 2
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F15 180 Ringing Proxy 2 -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
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To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F16 200 OK B -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F17 200 OK Proxy 2 -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
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a=rtpmap:0 PCMU/8000
F18 ACK A -> Proxy 2
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss2.biloxi.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 ACK
Content-Length: 0
F19 ACK Proxy 2 -> B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 2 ACK
Content-Length: 0
/* RTP streams are established between A and B */
/* User B Hangs Up with User A. */
F20 BYE User B -> Proxy 2
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
Max-Forwards: 70
Route: <sip:ss2.biloxi.com;lr>
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F21 BYE Proxy 2 -> User A
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
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;received=192.168.200.201
Max-Forwards: 69
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F22 200 OK User A -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F23 200 OK Proxy 2 -> User B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKnashds7
;received=192.168.200.201
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 4Fde34wkd11wsGFDs3@atlanta.com
CSeq: 1 BYE
Content-Length: 0
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3.1.5 Successful SIP to SIP through SIP ALG
User A ALG Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| INVITE F2 | |
| 100 F3 |--------------->| INVITE F4 |
|<---------------| 100 F5 |--------------->|
| |<---------------| 180 F6 |
| | 180 F7 |<---------------|
| 180 F8 |<---------------| |
|<---------------| | 200 F9 |
| | 200 F10 |<---------------|
| 200 F11 |<---------------| |
|<---------------| |
| ACK F12 | |
|--------------->| ACK F13 |
| |-------------------------------->|
| RTP Media | Both Way RTP Media |
|<==============>|<===============================>|
| BYE F14 | |
|--------------->| BYE F15 |
| |-------------------------------->|
| | 200 F16 |
| 200 F17 |<--------------------------------|
|<---------------| |
| | |
User A completes a call to User B through a ALG (Application Layer
Gateway) and a SIP Proxy. The routing through the ALG is
accomplished using a pre-loaded Route header in the INVITE F1. Note
that the media stream setup is not end-to-end - the ALG terminates
both media streams and bridges them. This is done by the ALG
modifying the SDP in the INVITE (F1) and 200 OK (F10) messages, and
possibly any 18x or ACK messages containing SDP.
In addition to firewall traversal, this Back-to-Back User Agent
(B2BUA) could be used as part of an anonymizer
service (in which all identifying information on User A would be
removed), or to perform codec media conversion, such as mu-law to A-
law conversion of PCM on an international call.
Also note that Proxy 2 does not Record-Route in this call flow.
Message Details
F1 INVITE A -> SIP ALG
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
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From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Route: <sip:alg1.atlanta.com;lr>
Proxy-Authorization: Digest username="UserA", realm="biloxi.com",
nonce="85b4f1cen4341ae6cbe5a3a9c8e88df9", opaque="",
uri="sip:UserB@biloxi.com",
response="b3f392f9218a328b9294076d708e6815"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Client for A prepares to receive data on port 49172 from the
network. */
F2 INVITE SIP ALG -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="biloxi.com",
nonce="85b4f1cen4341ae6cbe5a3a9c8e88df9", opaque="",
uri="sip:UserB@biloxi.com",
response="b3f392f9218a328b9294076d708e6815"
Content-Type: application/sdp
Content-Length: 146
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.255.128
t=0 0
m=audio 2000 RTP/AVP 0
a=rtpmap:0 PCMU/8000
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F3 100 Trying SIP ALG -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
/* SIP ALG prepares to proxy data from port 192.168.255.128/2000 to
192.168.100.101/49172. Proxy 2 uses a Location Service function to
determine where B is located. Based upon location analysis the call
is forwarded to User B */
F4 INVITE Proxy 2 -> B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 146
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.255.128
t=0 0
m=audio 2000 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F5 100 Trying Proxy 2 -> SIP ALG
SIP/2.0 100 Trying
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
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;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 180 Ringing B -> Proxy 2
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.156.222
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F7 180 Ringing Proxy 2 -> SIP ALG
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F8 180 Ringing SIP ALG -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Johnston, et al. Informational [Page 50]
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Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F9 200 OK B -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.156.222
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F10 200 OK Proxy 2 -> SIP ALG
SIP/2.0 200 OK
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
Johnston, et al. Informational [Page 51]
Internet Draft SIP Call Flow Examples July 2002
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F11 200 OK SIP ALG -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.255.128
t=0 0
m=audio 1734 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* The ALG prepares to proxy packets from 192.168.255.128/
1734 to 192.168.200.201/3456 */
F12 ACK A -> SIP ALG
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F13 ACK SIP ALG -> B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Johnston, et al. Informational [Page 52]
Internet Draft SIP Call Flow Examples July 2002
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* RTP streams are established between A and the ALG and
between the ALG and B*/
/* User A Hangs Up with User B. */
F14 BYE A -> SIP ALG
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:alg1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F15 BYE SIP ALG -> B
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F16 200 OK B -> SIP ALG
SIP/2.0 200 OK
Via: SIP/2.0/UDP alg1.atlanta.com:5060;branch=z9hG4bK739578.1
;received=192.168.255.128
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
Johnston, et al. Informational [Page 53]
Internet Draft SIP Call Flow Examples July 2002
F17 200 OK SIP ALG -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
Johnston, et al. Informational [Page 54]
Internet Draft SIP Call Flow Examples July 2002
3.1.6 Successful SIP to SIP via Redirect and Proxy with SDP in ACK
User A Redirect Server Proxy 3 User B
| | | |
| INVITE F1 | | |
|--------------->| | |
| 302 F2 | | |
|<---------------| | |
| ACK F3 | | |
|--------------->| | |
| INVITE F4 | |
|-------------------------------->| INVITE F5 |
| 100 F6 |--------------->|
|<--------------------------------| 180 F7 |
| 180 F8 |<---------------|
|<--------------------------------| |
| | 200 F9 |
| 200 F10 |<---------------|
|<--------------------------------| |
| ACK F11 | |
|-------------------------------->| ACK F12 |
| |--------------->|
| Both Way RTP Media |
|<================================================>|
| | BYE F13 |
| BYE F14 |<---------------|
|<--------------------------------| |
| 200 F15 | |
|-------------------------------->| 200 F16 |
| |--------------->|
| | |
In this scenario, User A places a call to User B using first a
Redirect server then a Proxy Server. The INVITE message is first
sent to the Redirect Server. The Server returns a 302 Moved
Temporarily response (F2) containing a Contact header with User B's
current SIP address. User A then generates a new INVITE and sends to
User B via the Proxy Server and the call proceeds normally. In this
example, no SDP is present in the INVITE, so the SDP is carried in
the ACK message.
The call is terminated when User B sends a BYE message.
Message Details
F1 INVITE A -> Redirect Server
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bKbf9f44
Max-Forwards: 70
Johnston, et al. Informational [Page 55]
Internet Draft SIP Call Flow Examples July 2002
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Length: 0
F2 302 Moved Temporarily Redirect Proxy -> A
SIP/2.0 302 Moved Temporarily
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bKbf9f44
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=53fHlqlQ2
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: sip:UserB@chicago.com
Content-Length: 0
F3 ACK A -> Redirect Server
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bKbf9f44
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=53fHlqlQ2
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F4 INVITE A -> Proxy 3
INVITE sip:UserB@chicago.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Length: 0
F5 INVITE Proxy 3 -> B
INVITE sip:UserB@192.168.200.100 SIP/2.0
Via: SIP/2.0/UDP ss3.chicago.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Johnston, et al. Informational [Page 56]
Internet Draft SIP Call Flow Examples July 2002
Max-Forwards: 69
Record-Route: <sip:ss3.chicago.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Length: 0
F6 100 Trying Proxy 3 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Content-Length: 0
F7 180 Ringing B -> Proxy 3
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss3.chicago.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.182.333
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss3.chicago.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.100>
Content-Length: 0
F8 180 Ringing Proxy 3 -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss3.chicago.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.100>
Content-Length: 0
Johnston, et al. Informational [Page 57]
Internet Draft SIP Call Flow Examples July 2002
F9 200 OK B -> Proxy 3
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss3.chicago.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.182.333
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss3.chicago.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.100>
Content-Type: application/sdp
Content-Length: 146
v=0
o=UserB 2890844527 2890844527 IN IP4 client.chicago.com
s=-
c=IN IP4 192.168.200.100
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F10 200 OK Proxy -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss3.chicago.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserB@192.168.200.100>
Content-Type: application/sdp
Content-Length: 146
v=0
o=UserB 2890844527 2890844527 IN IP4 client.chicago.com
s=-
c=IN IP4 192.168.200.100
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* ACK contains SDP of A since none present in INVITE */
F11 ACK A -> Proxy 3
Johnston, et al. Informational [Page 58]
Internet Draft SIP Call Flow Examples July 2002
ACK sip:UserB@192.168.200.100 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss3.chicago.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 ACK
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F12 ACK Proxy 3 -> B
ACK sip:UserB@111.112.112.114 SIP/2.0
Via: SIP/2.0/UDP ss3.chicago.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 ACK
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* RTP streams are established between A and B*/
/* User B Hangs Up with User A. */
F13 BYE B -> Proxy 3
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP client.chicago.com:5060;branch=z9hG4bKfgaw2
Max-Forwards: 70
Route: <sip:ss3.chicago.com;lr>
Johnston, et al. Informational [Page 59]
Internet Draft SIP Call Flow Examples July 2002
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F14 BYE Proxy 3 -> A
BYE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP ss3.chicago.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.200.100
Via: SIP/2.0/UDP client.chicago.com:5060;branch=z9hG4bKfgaw2
Max-Forwards: 69
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F15 200 OK A -> Proxy 3
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss3.chicago.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.182.333
Via: SIP/2.0/UDP client.chicago.com:5060;branch=z9hG4bKfgaw2
;received=192.168.200.100
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 BYE
Content-Length: 0
F16 200 OK Proxy 3 -> B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.chicago.com:5060;branch=z9hG4bKfgaw2
;received=192.168.200.100
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 BYE
Content-Length: 0
Johnston, et al. Informational [Page 60]
Internet Draft SIP Call Flow Examples July 2002
3.1.7 Successful SIP to SIP with re-INVITE (IP Address Change)
User A Proxy 2 User B
| F1 INVITE | |
|------------------->| F2 INVITE |
| F3 100 Trying |------------------->|
|<-------------------| F4 180 Ringing |
| F5 180 Ringing |<-------------------|
|<-------------------| |
| | F6 200 OK |
| F7 200 OK |<-------------------|
|<-------------------| |
| F8 ACK |
|---------------------------------------->|
| Both Way RTP Media Established |
|<=======================================>|
| |
| B changes IP address |
| |
| F9 INVITE |
|<----------------------------------------|
| F10 200 OK |
|---------------------------------------->|
| F11 ACK |
|<----------------------------------------|
| New RTP Media Stream |
|<=======================================>|
| F12 BYE |
|---------------------------------------->|
| F25 200 OK |
|<----------------------------------------|
| |
This example shows a session in which the media is changes midway
through the session. When User B?s IP address changes during the
session, User B sends a re-INVITE containing a new Contact and SDP
(version number incremented) information to A. In this flow, the
proxy does not Record-Route so is not in the SIP messaging path after
the initial exchange.
Message Details
F1 INVITE A -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Johnston, et al. Informational [Page 61]
Internet Draft SIP Call Flow Examples July 2002
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 INVITE Proxy 2 -> B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F3 100 Trying Proxy 2 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F4 180 Ringing B -> Proxy 2
Johnston, et al. Informational [Page 62]
Internet Draft SIP Call Flow Examples July 2002
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F5 180 Ringing Proxy 2 -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F6 200 OK B -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.156.222
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F7 200 OK Proxy 2 -> A
Johnston, et al. Informational [Page 63]
Internet Draft SIP Call Flow Examples July 2002
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F8 ACK A -> B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* RTP streams are established between A and B */
/* B changes IP address and re-INVITEs A with new Contact and SDP */
F9 INVITE B -> A
INVITE sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKlkld5l
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 14 INVITE
Contact: <sip:UserB@192.168.200.100>
Content-Type: application/sdp
Content-Length: 147
v=0
Johnston, et al. Informational [Page 64]
Internet Draft SIP Call Flow Examples July 2002
o=UserB 2890844527 2890844528 IN IP4 client.chicago.com
s=-
c=IN IP4 192.168.200.100
t=0 0
m=audio 47172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F10 200 OK A ->B
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.chicago.com:5060;branch=z9hG4bKlkld5l
;received=192.168.200.100
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 14 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 1000 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F11 ACK B -> A
ACK sip:UserA@192.168.100.101 SIP/2.0
Via: SIP/2.0/UDP client.biloxi.com:5060;branch=z9hG4bKlkld5l
Max-Forwards: 70
From: LittleGuy <sip:UserB@biloxi.com>;tag=314159
To: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 14 ACK
Content-Length: 0
/* New RTP stream established between A and B */
/* A hangs up with B */
F12 BYE A -> B
BYE sip:UserB@192.168.200.100 SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Johnston, et al. Informational [Page 65]
Internet Draft SIP Call Flow Examples July 2002
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F13 200 OK B -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
Johnston, et al. Informational [Page 66]
Internet Draft SIP Call Flow Examples July 2002
3.2 Failure Scenarios
3.2.1 Unsuccessful SIP to SIP no answer
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| INVITE F2 | |
| 100 F3 |--------------->| INVITE F4 |
|<---------------| 100 F5 |--------------->|
| |<---------------| |
| | | 180 F6 |
| | 180 F7 |<---------------|
| 180 F8 |<---------------| |
|<---------------| | |
| | | |
| CANCEL F9 | | |
|--------------->| | |
| 200 F10 | | |
|<---------------| CANCEL F11 | |
| |--------------->| |
| | 200 F12 | |
| |<---------------| |
| | | CANCEL F13 |
| | |--------------->|
| | | 200 F14 |
| | |<---------------|
| | | 487 F15 |
| | |<---------------|
| | | ACK F16 |
| | 487 F17 |--------------->|
| |<---------------| |
| | ACK F18 | |
| 487 F19 |--------------->| |
|<---------------| | |
| ACK F20 | | |
|--------------->| | |
| | | |
In this scenario, User A gives up on the call before User B answers
(sends a 200 OK response). User A sends a CANCEL (F9) since no final
response had been received from User B. If a 200 OK to the INVITE
had crossed with the CANCEL, User A would have sent an ACK then a BYE
to User B in order to properly terminate the call.
Note that the CANCEL message is acknowledged with a 200 OK on a hop
by hop basis, rather than end to end.
Johnston, et al. Informational [Page 67]
Internet Draft SIP Call Flow Examples July 2002
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="ze7k1ee88df84f1cec431ae6cbe5a359", opaque="",
uri="sip:UserB@biloxi.com",
response="b00b416324679d7e243f55708d44be7b"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/*Client for A prepares to receive data on port 49172 from the
network.*/
F2 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
Johnston, et al. Informational [Page 68]
Internet Draft SIP Call Flow Examples July 2002
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F3 100 Trying Proxy 1 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F4 INVITE Proxy 2 -> B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.client.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
Max-Forwards: 68
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F5 100 Trying Proxy 2 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Johnston, et al. Informational [Page 69]
Internet Draft SIP Call Flow Examples July 2002
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 180 Ringing B -> Proxy 2
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss2.client.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F7 180 Ringing Proxy 2 -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F8 180 Ringing Proxy 1 -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Johnston, et al. Informational [Page 70]
Internet Draft SIP Call Flow Examples July 2002
Content-Length: 0
F9 CANCEL A -> Proxy 1
CANCEL sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F10 200 OK Proxy 1 -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F11 CANCEL Proxy 1 -> Proxy 2
CANCEL sip:UserA@atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F12 200 OK Proxy 2 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F13 CANCEL Proxy 2 -> B
Johnston, et al. Informational [Page 71]
Internet Draft SIP Call Flow Examples July 2002
CANCEL sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F14 200 OK B -> Proxy 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F15 487 Request Terminated B -> Proxy 2
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F16 ACK Proxy 2 -> B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F17 487 Request Terminated Proxy 2 -> Proxy 1
Johnston, et al. Informational [Page 72]
Internet Draft SIP Call Flow Examples July 2002
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F18 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F19 487 Request Terminated Proxy 1 -> A
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
F20 ACK A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
Johnston, et al. Informational [Page 73]
Internet Draft SIP Call Flow Examples July 2002
3.2.2 Unsuccessful SIP to SIP busy
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| INVITE F2 | |
| 100 F3 |--------------->| INVITE F4 |
|<---------------| 100 F5 |--------------->|
| |<---------------| |
| | | 486 F6 |
| | |<---------------|
| | | ACK F7 |
| | 486 F8 |--------------->|
| |<---------------| |
| | ACK F9 | |
| 486 F10 |--------------->| |
|<---------------| | |
| ACK F11 | | |
|--------------->| | |
| | | |
In this scenario, User B is busy and sends a 486 Busy Here response
to User A's INVITE. Note that the non-2xx response is acknowleged on
a hop-by-hop basis instead of end-to-end.
Message Details
F1 INVITE User A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="dc3a5ab2530aa93112cf5904ba7d88fa", opaque="",
uri="sip:UserB@biloxi.com",
response="702138b27d869ac8741e10ec643d55be"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
Johnston, et al. Informational [Page 74]
Internet Draft SIP Call Flow Examples July 2002
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/*Client for A prepares to receive data on port 49172 from the
network.*/
F2 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F3 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F4 INVITE Proxy 2 -> User B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Johnston, et al. Informational [Page 75]
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Max-Forwards: 68
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F5 100 Trying Proxy 2 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 486 Busy Here User B -> Proxy 2
SIP/2.0 486 Busy Here
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F7 ACK Proxy 2 -> User B
ACK sip:UserB@192.168.200.201 SIP/2.0
Johnston, et al. Informational [Page 76]
Internet Draft SIP Call Flow Examples July 2002
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F8 486 Busy Here Proxy 2 -> Proxy 1
SIP/2.0 486 Busy Here
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F9 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F10 486 Busy Here Proxy 1 -> User A
SIP/2.0 486 Busy Here
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F11 ACK User A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Johnston, et al. Informational [Page 77]
Internet Draft SIP Call Flow Examples July 2002
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
Johnston, et al. Informational [Page 78]
Internet Draft SIP Call Flow Examples July 2002
3.2.3 Unsuccessful SIP to SIP no response
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| INVITE F2 | |
| 100 F3 |--------------->| INVITE F4 |
|<---------------| 100 F5 |--------------->|
| |<---------------| INVITE F6 |
| | |--------------->|
| | | INVITE F7 |
| | |--------------->|
| | | INVITE F8 |
| | |--------------->|
| | | INVITE F9 |
| | |--------------->|
| | | INVITE F10 |
| | |--------------->|
| | | INVITE F11 |
| | 480 F12 |--------------->|
| |<---------------| |
| | ACK F13 | |
| 480 F14 |--------------->| |
|<---------------| | |
| ACK F15 | | |
|--------------->| | |
| | | |
In this example, there is no response from User B to User A's INVITE
messages being re-transmitted by Proxy 2. After the sixth re-
transmission, Proxy 2 gives up and sends a 480 No Response to User A.
Message Details
F1 INVITE User A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="cf5904ba7d8dc3a5ab2530aa931128fa", opaque="",
uri="sip:UserB@biloxi.com",
response="7afc04be7961f053c24f80e7dbaf888f"
Content-Type: application/sdp
Johnston, et al. Informational [Page 79]
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Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/*Client for A prepares to receive data on port 49172 from the
network.*/
F2 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F3 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F4 INVITE Proxy 2 -> User B
Johnston, et al. Informational [Page 80]
Internet Draft SIP Call Flow Examples July 2002
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F5 100 Trying Proxy 2 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 INVITE Proxy 2 -> User B
Resend of Message F4
F7 INVITE Proxy 2 -> User B
Resend of Message F4
F8 INVITE Proxy 2 -> User B
Johnston, et al. Informational [Page 81]
Internet Draft SIP Call Flow Examples July 2002
Resend of Message F4
F9 INVITE Proxy 2 -> User B
Resend of Message F4
F10 INVITE Proxy 2 -> User B
Resend of Message F4
F11 INVITE Proxy 2 -> User B
Resend of Message F4
/* Proxy 2 gives up */
F12 480 No Response Proxy 2 -> Proxy 1
SIP/2.0 480 No Response
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F13 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F14 480 No Response Proxy 1 -> User A
SIP/2.0 480 No Response
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
Johnston, et al. Informational [Page 82]
Internet Draft SIP Call Flow Examples July 2002
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F15 ACK User A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
Johnston, et al. Informational [Page 83]
Internet Draft SIP Call Flow Examples July 2002
3.2.4 Unsuccessful SIP to SIP Temporarily Unavailable
User A Proxy 1 Proxy 2 User B
| | | |
| INVITE F1 | | |
|--------------->| INVITE F2 | |
| 100 F3 |--------------->| INVITE F4 |
|<---------------| 100 F5 |--------------->|
| |<---------------| 180 F6 |
| | 180 F7 |<---------------|
| 180 F8 |<---------------| |
|<---------------| | 480 F9 |
| | |<---------------|
| | | ACK F10 |
| | 480 F11 |--------------->|
| |<---------------| |
| | ACK F12 | |
| 480 F13 |--------------->| |
|<---------------| | |
| ACK F14 | | |
|--------------->| | |
| | | |
In this scenario, User B initially sends a 180 Ringing response to
User A, indicating that alerting is taking place. However, then a
480 Unavailable is then sent to User A. This response is
acknowledged then proxied back to User A.
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="aa9311cf5904ba7d8dc3a5ab253028fa", opaque="",
uri="sip:UserB@biloxi.com",
response="59a46a91bf1646562a4d486c84b399db"
Content-Type: application/sdp
Content-Length: 147
v=0
Johnston, et al. Informational [Page 84]
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o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/*Client for A prepares to receive data on port 49172 from the
network.*/
F2 INVITE Proxy 1 -> Proxy 2
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F3 100 Trying Proxy 1 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F4 INVITE Proxy 2 -> B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Johnston, et al. Informational [Page 85]
Internet Draft SIP Call Flow Examples July 2002
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 68
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F5 100 Trying Proxy 2 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 180 Ringing B -> Proxy 2
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Johnston, et al. Informational [Page 86]
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Content-Length: 0
F7 180 Ringing Proxy 2 -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F8 180 Ringing Proxy 1 -> A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss2.biloxi.com;lr>, <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F9 480 Temporarily Unavailable B -> Proxy 2
SIP/2.0 480 Temporarily Unavailable
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
;received=192.168.156.222
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F10 ACK Proxy 2 -> B
ACK sip:UserB@192.168.200.201 SIP/2.0
Johnston, et al. Informational [Page 87]
Internet Draft SIP Call Flow Examples July 2002
Via: SIP/2.0/UDP ss2.biloxi.com:5060;branch=z9hG4bK721e418c4.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F11 480 Temporarily Unavailable Proxy 2 -> Proxy 1
SIP/2.0 480 Temporarily Unavailable
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F12 ACK Proxy 1 -> Proxy 2
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F13 480 Temporarily Unavailable Proxy 1 -> A
SIP/2.0 480 Temporarily Unavailable
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F14 ACK A -> Proxy 1
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Johnston, et al. Informational [Page 88]
Internet Draft SIP Call Flow Examples July 2002
From: BigGuy <sip:UserA@atlanta.com>;tag=9fxced76sl
To: LittleGuy <sip:UserB@biloxi.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
Johnston, et al. Informational [Page 89]
Internet Draft SIP Call Flow Examples July 2002
4 SIP to Gateway Dialing
In the following scenarios, User A (BigGuy sip:UserA@atlanta.com) is
a SIP phone or other SIP-enabled device. User B is reachable via the
PSTN at global telephone number +19725552222. User A places a call
to User B through a Proxy Server Proxy 1 and a Network Gateway. In
other scenarios, User A places calls to User C, who is served via a
PBX (Private Branch Exchange) and is identified by a private
extension 444-3333, or global number +1-918-555-3333. Note that User
A uses his/her global telephone number +1-314-555-1111 in the From
header in the INVITE messages. This then gives the Gateway the
option of using this header to populate the calling party
identification field in subsequent signaling (CgPN in ISUP). Left
open is the issue of how the Gateway can determine the accuracy of
the telephone number, necessary before passing it as a valid CgPN in
the PSTN.
There is a major difference in the call flows in this section. In-
band alerting (ringing tone, busy tone, recorded announcements, etc.)
may be present in the PSTN speech path after the receipt of the SS7
Address Complete Message (ACM) which maps to the SIP 180 Ringing
response. To establish a two way media path prior to the call being
answered (200 OK), a 183 Session Progress response is sent instead of
a 180 Ringing. Note that since this 183 response is not sent
reliably, it should be periodically resent by the gateway. The same
SDP in the 183 should also be present in the 200 OK when the call is
answered.
4.1 Success Scenarios
In these scenarios, User A is a SIP phone or other SIP-enabled
device. User A places a call to User B in the PSTN or User C on a
PBX through a Proxy Server and a Gateway.
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4.1.1 Successful SIP to ISUP PSTN call
User A Proxy 1 NGW 1 Switch B
| | | |
| INVITE F1 | | |
|--------------->| | |
| 100 F2 | | |
|<---------------| INVITE F3 | |
| |--------------->| |
| | 100 F4 | |
| |<---------------| IAM F5 |
| | |--------------->|
| | | ACM F6 |
| | 183 F7 |<---------------|
| 183 F8 |<---------------| |
|<---------------| | |
| Both Way RTP Media | One Way Voice |
|<===============================>|<===============|
| | | ANM F9 |
| | 200 F10 |<---------------|
| 200 F11 |<---------------| |
|<---------------| | |
| ACK F12 | | |
|--------------->| ACK F13 | |
| |--------------->| |
| Both Way RTP Media | Both Way Voice |
|<===============================>|<==============>|
| BYE F14 | | |
|--------------->| BYE F15 | |
| |--------------->| |
| | 200 F16 | |
| 200 F17 |<---------------| REL F18 |
|<---------------| |--------------->|
| | | RLC F19 |
| | |<---------------|
| | | |
User A dials the globalized E.164 number +19725552222 to reach
User B. Note that A might have only dialed the last 7 digits, or
some other dialing plan. It is assumed that the SIP User Agent
Client converts the digits into a global number and puts them into a
SIP URI. Note that tel URIs could be used instead of SIP URIs.
User A could use either their SIP address (sip:UserA@atlanta.com) or
SIP telephone number (sip:+13145551111@ss1.atlanta.com;user=phone) in
the From header. In this example, the telephone number is included,
and it is shown as being passed as calling party identification
through the Network Gateway (NGW 1) to User B (F5). Note that for
this number to be passed into the SS7 network, it would have to be
somehow verified for accuracy.
Johnston, et al. Informational [Page 91]
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In this scenario, User B answers the call then User A disconnects the
call. Signaling between NGW 1 and User B's telephone switch is ANSI
ISUP. For the details of SIP to ISUP mapping, refer to [SIP-ISUP].
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA", realm="atlanta.com",
nonce="dc3a5ab25302aa931904ba7d88fa1cf5", opaque="",
uri="sip:+19725552222@ss1.atlanta.com;user=phone",
response="ccdca50cb091d587421457305d097458c"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
/* Proxy 1 uses a Location Service function to determine the gateway
for terminating this call. The call is forwarded to NGW 1. Client
for A prepares to receive data on port 49172 from the
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network.*/
F3 INVITE Proxy 1 -> NGW 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying NGW 1 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 IAM NGW 1 -> User B
IAM
CdPN=972-555-2222,NPI=E.164,NOA=National
CgPN=314-555-1111,NPI=E.164,NOA=National
F6 ACM User B -> NGW 1
ACM
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F7 183 Session Progress NGW 1 -> Proxy 1
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* NGW 1 sends PSTN audio (ringing) in the RTP path to A */
F8 183 Session Progress Proxy 1 -> User A
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
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a=rtpmap:0 PCMU/8000
F9 ANM User B -> NGW 1
ANM
F10 200 OK NGW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F11 200 OK Proxy 1 -> User A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
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o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F12 ACK A -> Proxy 1
ACK sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F13 ACK Proxy 1 -> NGW 1
ACK sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* User A Hangs Up with User B. */
F14 BYE A -> Proxy 1
BYE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
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CSeq: 2 BYE
Content-Length: 0
F15 BYE Proxy 1 -> NGW 1
BYE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F16 200 OK NGW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F17 200 OK Proxy 1 -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F18 REL NGW 1 -> B
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REL
CauseCode=16 Normal
F19 RLC B -> NGW 1
RLC
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4.1.2 Successful SIP to ISDN PBX call
User A Proxy 1 GW 1 PBX C
| | | |
| INVITE F1 | | |
|--------------->| | |
| 100 F2 | | |
|<---------------| INVITE F3 | |
| |--------------->| |
| | 100 F4 | |
| |<---------------| SETUP F5 |
| | |--------------->|
| | | CALL PROC F6 |
| | |<---------------|
| | | PROGress F7 |
| | 180 F8 |<---------------|
| 180 F9 |<---------------| |
|<---------------| | |
| | | One Way Voice |
| | |<===============|
| | | CONNect F10 |
| | |<---------------|
| | | CONNect ACK F11|
| | 200 F12 |--------------->|
| 200 F13 |<---------------| |
|<---------------| | |
| ACK F14 | | |
|--------------->| ACK F15 | |
| |--------------->| |
| Both Way RTP Media | Both Way Voice |
|<===============================>|<==============>|
| BYE F16 | | |
|--------------->| BYE F17 | |
| |--------------->| |
| | 200 F18 | |
| 200 F19 |<---------------| DISConnect F20 |
|<---------------| |--------------->|
| | | RELease F21 |
| | |<---------------|
| | | RELease COM F22|
| | |--------------->|
| | | |
User A is a SIP device while User C is connected via a
Gateway (GW 1) to a PBX. The PBX connection is via a ISDN trunk
group. User A dials User C's telephone number (918-555-3333) which
is globalized and put into a SIP URI.
The host portion of the Request-URI in the INVITE F3 is used to
identify the context (customer, trunk group, or line) in which the
private number 444-3333 is valid. Otherwise, this INVITE message
could get forwarded by GW 1 and the context of the digits could
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become lost and the call unroutable.
Proxy 1 looks up the telephone number and locates the gateway that
serves User C. User C is identified by its extension
(444-3333) in the Request-URI sent to GW 1.
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:+19185553333@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA",
realm="atlanta.com", nonce="qo0dc3a5ab22aa931904badfa1cf5j9h",
opaque="", uri="sip:+19185553333@ss1.atlanta.com;user=phone",
response="6c792f5c9fa360358b93c7fb826bf550"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Content-Length: 0
F3 INVITE Proxy 1 -> GW 1
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INVITE sip:4443333@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying GW -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Content-Length: 0
F5 SETUP GW 1 -> User C
Protocol discriminator=Q.931
Message type=SETUP
Bearer capability: Information transfer capability=0 (Speech) or 16
(3.1 kHz audio)
Channel identification=Preferred or exclusive B-channel
Progress indicator=1 (Call is not end-to-end ISDN;further call
progress information may be available inband)
Called party number:
Type of number unknown
Digits=444-3333
F6 CALL PROCeeding User C -> GW 1
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Protocol discriminator=Q.931
Message type=CALL PROC
Channel identification=Exclusive B-channel
F7 PROGress User C -> GW 1
Protocol discriminator=Q.931
Message type=PROG
Progress indicator=1 (Call is not end-to-end ISDN;further call
progress information may be available inband)
F8 180 Ringing GW 1 -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:4443333@gw1.atlanta.com>
Content-Length: 0
F9 180 Ringing Proxy 1 -> User A
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:4443333@gw1.atlanta.com>
Content-Length: 0
F10 CONNect User C -> GW 1
Protocol discriminator=Q.931
Message type=CONN
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F11 CONNect ACK GW 1 -> User C
Protocol discriminator=Q.931
Message type=CONN ACK
F12 200 OK GW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:4443333@gw1.atlanta.com>
Content-Type: application/sdp
Content-Length: 140
v=0
o=GW 2890844527 2890844527 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F13 200 OK Proxy 1 -> User A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 INVITE
Contact: <sip:4443333@gw1.atlanta.com>
Content-Type: application/sdp
Content-Length: 140
v=0
o=GW 2890844527 2890844527 IN IP4 gw1.atlanta.com
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s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F14 ACK A -> Proxy 1
ACK sip:4443333@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 ACK
Content-Length: 0
F15 ACK Proxy 1 -> GW 1
ACK sip:4443333@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 ACK
Content-Length: 0
/* User A Hangs Up with User B. */
F16 BYE A -> Proxy 1
BYE sip:4443333@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 BYE
Johnston, et al. Informational [Page 104]
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Content-Length: 0
F17 BYE Proxy 1 -> GW 1
BYE sip:4443333@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 BYE
Content-Length: 0
F18 200 OK GW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 BYE
Content-Length: 0
F19 200 OK Proxy 1 -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: OtherGuy <sip:+19185553333@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 3 BYE
Content-Length: 0
F20 DISConnect GW 1 -> User C
Protocol discriminator=Q.931
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Message type=DISC
Cause=16 (Normal clearing)
F21 RELease User C -> GW 1
Protocol discriminator=Q.931
Message type=REL
F22 RELease COMplete GW 1 -> User C
Protocol discriminator=Q.931
Message type=REL COM
Johnston, et al. Informational [Page 106]
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4.1.3 Successful SIP to ISUP PSTN call with overflow
User A Proxy 1 NGW 1 NGW 2 Switch B
| | | | |
| INVITE F1 | | | |
|------------->| | | |
| | INVITE F2 | | |
| 100 F3 |------------->| | |
|<-------------| 503 F4 | | |
| |<-------------| | |
| | ACK F5 | | |
| |------------->| | |
| | INVITE F6 | |
| |---------------------------->| IAM F7 |
| | |------------->|
| | | ACM F8 |
| | 183 F9 |<-------------|
| 183 F10 |<----------------------------| |
|<-------------| | |
| Two Way RTP Media | One Way Voice|
|<==========================================>|<=============|
| | | ANM F11 |
| | 200 F12 |<-------------|
| 200 F13 |<----------------------------| |
|<-------------| | |
| ACK F14 | | |
|------------->| ACK F15 | |
| |---------------------------->| |
| Both Way RTP Media |Both Way Voice|
|<==========================================>|<============>|
| BYE F16 | | |
|------------->| BYE F17 | |
| |---------------------------->| |
| | 200 F18 | |
| 200 F19 |<----------------------------| REL F20 |
|<-------------| |------------->|
| | | RLC F21 |
| | |<-------------|
| | | |
User A calls User B through Proxy 1. Proxy 1 tries to route to a
Network Gateway NGW 1. NGW 1 is not available and responds with a 503
Service Unavailable (F4). The call is then routed to Network Gateway
NGW 2. User B answers the call. The call is terminated when User A
disconnects the call. NGW 2 and User B's telephone switch use ANSI
ISUP signaling.
Message Details
F1 INVITE A -> Proxy 1
Johnston, et al. Informational [Page 107]
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INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA",
realm="atlanta.com", nonce="b59311c3ba05b401cf80b2a2c5ac51b0",
opaque="", uri="sip:+19725552222@ss1.atlanta.com;user=phone",
response="ba6ab44923fa2614b28e3e3957789ab0"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine where B is
located. Proxy 1 receives a primary route NGW 1 and a secondary
route NGW 2. NGW 1 is tried first */
F2 INVITE Proxy 1 -> NGW 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
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a=rtpmap:0 PCMU/8000
F3 100 Trying Proxy 1 -> User A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F4 503 Service Unavailable NGW 1 -> Proxy 1
SIP/2.0 503 Service Unavailable
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 ACK Proxy 1 -> NGW 1
ACK sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com>;user=phone>
;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* Proxy 1 now tries secondary route to NGW 2 */
F6 INVITE Proxy 1 -> NGW 2
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INVITE sip:+19725552222@ngw2.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F7 IAM NGW 2 -> User B
IAM
CdPN=972-555-2222,NPI=E.164,NOA=National
CgPN=314-555-1111,NPI=E.164,NOA=National
F8 ACM User B -> NGW 2
ACM
F9 183 Session Progress NGW 2 -> Proxy 1
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw2.atlanta.com;user=phone>
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Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw2.atlanta.com
s=-
c=IN IP4 192.168.255.102
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* RTP packets are sent by GW to A for audio (e.g. ring tone) */
F10 183 Session Progress Proxy 1 -> User A
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw2.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw2.atlanta.com
s=-
c=IN IP4 192.168.255.102
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F11 ANM User B -> NGW 2
ANM
F12 200 OK NGW 2 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
Johnston, et al. Informational [Page 111]
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From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw2.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw2.atlanta.com
s=-
c=IN IP4 192.168.255.102
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F13 200 OK Proxy 1 -> User A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw2.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw2.atlanta.com
s=-
c=IN IP4 192.168.255.102
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F14 ACK A -> Proxy 1
ACK sip:+19725552222@ngw2.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
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To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F15 ACK Proxy 1 -> NGW 2
ACK sip:+19725552222@ngw2.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* RTP streams are established between A and B(via the GW) */
/* User A Hangs Up with User B. */
F16 BYE A -> Proxy 1
BYE sip:+19725552222@ngw2.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
Route: <ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F17 BYE Proxy 1 -> NGW 2
BYE sip:+19725552222@ngw2.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
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;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F18 200 OK NGW 2 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F19 200 OK Proxy 1 -> User A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 2 BYE
Content-Length: 0
F20 REL NGW 2 -> B
REL
CauseCode=16 Normal
F21 RLC B -> NGW 2
RLC
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4.2 Failure Scenarios
In these failure scenarios, the call does not complete. In most
cases, however, a media stream is still setup. This is due to the
fact that most failures in dialing to the PSTN result in in-band
tones (busy, reorder tones or announcements - "The number you have
dialed has changed. The new number is..."). The 183 Session
Progress response containing SDP media information is used to
setup this early media path so that the caller User A knows the final
disposition of the call.
The media stream is either terminated by the caller after the tone or
announcement has been heard and understood, or by the Gateway after a
timer expires.
In other failure scenarios, a SS7 Release with Cause Code is mapped
to a SIP response. In these scenarios, the early media path is not
used, but the actual failure code is conveyed to the caller by the
SIP User Agent Client.
Johnston, et al. Informational [Page 115]
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4.2.1 Unsuccessful SIP to PSTN call: Treatment from PSTN
User A Proxy 1 NGW 1 User B
| | | |
| INVITE F1 | | |
|--------------->| | |
| 100 F2 | | |
|<---------------| INVITE F3 | |
| |--------------->| |
| | 100 F4 | |
| |<---------------| IAM F5 |
| | |--------------->|
| | | ACM F6 |
| | 183 F7 |<---------------|
| 183 F8 |<---------------| |
|<---------------| | |
| Two Way RTP Media | One Way Voice |
|<===============================>|<===============|
| Treatment Applied |
|<=================================================|
| CANCEL F9 | | |
|--------------->| | |
| 200 F10 | | |
|<---------------| CANCEL F11 | |
| |--------------->| |
| | 200 F12 | |
| |<---------------| REL F13 |
| | |--------------->|
| | | RLC F14 |
| | 487 F15 |<---------------|
| |<---------------| |
| | ACK F16 | |
| 487 F17 |--------------->| |
|<---------------| | |
| ACK F18 | | |
|--------------->| | |
| | | |
User A calls User B in the PSTN through a proxy server Proxy 1 and a
Network Gateway NGW 1. The call is rejected by the PSTN with an in-
band treatment (tone or recording) played. User A hears the
treatment and then hangs up, which results in a CANCEL (F9) being
sent to terminate the call. (A BYE is not sent since no final
response was ever received by User A.)
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
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Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA",
realm="atlanta.com", nonce="01cf8311c3b0b2a2c5ac51bb59a05b40",
opaque="", uri="sip:+19725552222@ss1.atlanta.com;user=phone",
response="e178fbe430e6680a1690261af8831f40"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 100 Trying Proxy 1 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
/* Proxy 1 uses a Location Service function to determine where B is
located. Based upon location analysis the call is forwarded to NGW
1. Client for A prepares to receive data on port 49172 from the
network. */
F3 INVITE Proxy 1 -> NGW 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
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To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying NGW 1 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 IAM NGW 1 -> User B
IAM
CdPN=972-555-2222,NPI=E.164,NOA=National
CgPN=314-555-1111,NPI=E.164,NOA=National
F6 ACM User B -> NGW 1
ACM
F7 183 Session Progress NGW 1 -> Proxy 1
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
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;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F8 183 Session Progress Proxy 1 -> User A
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Caller hears the recorded announcement, then hangs up */
F9 CANCEL A -> Proxy 1
CANCEL sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
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To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F10 200 OK Proxy 1 -> A
SIP/2.0 200 OK
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F11 CANCEL Proxy 1 -> NGW 1
CANCEL sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F12 200 OK NGW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F13 REL NGW 1 -> B
REL
CauseCode=18 No user responding
F14 RLC B -> NGW 1
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RLC
F15 487 Request Terminated NGW 1 -> Proxy 1
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F16 ACK Proxy 1 -> NGW 1
ACK sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F17 487 Request Terminated Proxy 1 -> A
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F18 ACK A -> Proxy 1
ACK sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
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Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
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4.2.2 Unsuccessful SIP to PSTN: REL w/Cause from PSTN
User A Proxy 1 NGW 1 Switch B
| | | |
| INVITE F1 | | |
|--------------->| | |
| 100 F2 | | |
|<---------------| INVITE F3 | |
| |--------------->| |
| | 100 F4 | |
| |<---------------| IAM F5 |
| | |--------------->|
| | | REL(1) F6 |
| | |<---------------|
| | | RLC F7 |
| | 404 F8 |--------------->|
| |<---------------| |
| | ACK F9 | |
| |--------------->| |
| 404 F10 | | |
|<---------------| | |
| ACK F11 | | |
|--------------->| | |
| | | |
User A calls PSTN User B through a Proxy Server Proxy 1 and a Network
Gateway NGW 1. The call is rejected by the PSTN with a
ANSI ISUP Release message REL containing a specific Cause code.
This cause value (1) is mapped by the Gateway to a SIP 404 Address
Incomplete response which is proxied back to User A. For more
details of ISUP cause value to SIP responses refer to [SIP-ISUP].
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:+44-1234@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA",
realm="atlanta.com", nonce="j1c3b0b01cf832da2c5ac51bb59a05b40",
opaque="", uri="sip:+44-1234@ss1.atlanta.com;user=phone",
response="a451358d46b55512863efe1dccaa2f42"
Content-Type: application/sdp
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Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F2 100 Trying Proxy 1 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
/* Proxy 1 uses a Location Service function to determine where B is
located. Based upon location analysis the call is forwarded to NGW1.
Client for A prepares to receive data on port 49172 from the network.
*/
F3 INVITE Proxy 1 -> NGW 1
INVITE sip:+44-1234@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
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a=rtpmap:0 PCMU/8000
F4 100 Trying NGW 1 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 IAM NGW 1 -> User B
IAM
CdPN=44-1234,NPI=E.164,NOA=International
CgPN=314-555-1111,NPI=E.164,NOA=National
F6 REL User B -> NGW 1
REL
CauseValue=1 Unallocated number
F7 RLC NGW 1 -> User B
RLC
/* Network Gateway maps CauseValue=1 to the SIP message 404 Not
Found */
F8 404 Not Found NGW 1 -> Proxy 1
SIP/2.0 404 Not Found
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Error-Info: <sip:not-found-ann@ann.atlanta.com>
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Content-Length: 0
F9 ACK Proxy 1 -> NGW 1
ACK sip:+44-1234@ngw1.atlanta.com;user=phone SIP/2.0
Max-Forwards: 70
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F10 404 Not Found Proxy 1 -> User A
SIP/2.0 404 Not Found
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Error-Info: <sip:not-found-ann@ann.atlanta.com>
Content-Length: 0
F11 ACK User A -> Proxy 1
ACK sip:+44-1234@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+44-1234@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
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4.2.3 Unsuccessful SIP to PSTN: ANM Timeout
User A Proxy 1 NGW 1 Switch B
| | | |
| INVITE F1 | | |
|--------------->| | |
| 100 F2 | | |
|<---------------| INVITE F3 | |
| |--------------->| |
| | 100 F4 | |
| |<---------------| IAM F5 |
| | |--------------->|
| | | ACM F6 |
| | 183 F7 |<---------------|
| 183 F8 |<---------------| |
|<---------------| | |
| | Timer on NGW 1 Expires |
| | | |
| | | REL F9 |
| | |--------------->|
| | | RLC F10 |
| | 480 F11 |<---------------|
| |<---------------| |
| | ACK F12 | |
| |--------------->| |
| 480 F13 | | |
|<---------------| | |
| ACK F14 | | |
|--------------->| | |
User A calls User B in the PSTN through a proxy server Proxy 1 and
Network Gateway NGW 1. The call is released by the Gateway after a
timer expires due to no ANswer Message (ANM) being received. The
Gateway sends an ISUP Release REL message to the PSTN and a 480
Temporarily Unavailable response to User A in the SIP network.
Message Details
F1 INVITE A -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Proxy-Authorization: Digest username="UserA",
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realm="atlanta.com", nonce="da2c5ac51bb59a05j1c3b0b01cf832b40",
opaque="", uri="sip:+19725552222@ss1.atlanta.com;user=phone",
response="579cb9db184cdc25bf816f37cbc03c7d"
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine where B is
located. Based upon location analysis the call is forwarded to NGW
1. Client for A prepares to receive data on port 49172 from the
network.*/
F2 100 Trying Proxy 1 -> A
SIP/2.0 100 Trying
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F3 INVITE Proxy 1 -> NGW 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserA@192.168.100.101>
Content-Type: application/sdp
Content-Length: 147
v=0
o=UserA 2890844526 2890844526 IN IP4 client.atlanta.com
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s=-
c=IN IP4 192.168.100.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying NGW 1 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 IAM NGW 1 -> User B
IAM
CdPN=972-555-2222,NPI=E.164,NOA=National
CgPN=314-555-1111,NPI=E.164,NOA=National
F6 ACM User B -> NGW 1
ACM
F7 183 Session Progress NGW 1 -> Proxy 1
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
Johnston, et al. Informational [Page 129]
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v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F8 183 Session Progress Proxy 1 -> User A
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19725552222@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* After NGW 1's timer expires, Network Gateway sends REL to ISUP
network and 480 to SIP network */
F9 REL NGW 1 -> User B
REL
CauseCode=18 No user responding
F10 RLC User B -> NGW 1
RLC
F11 480 Temporarily Unavailable NGW 1 -> Proxy 1
SIP/2.0 480 Temporarily Unavailable
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
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;received=192.168.255.111
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Error-Info: <sip:temp-unavail-ann@ann.atlanta.com>
Content-Length: 0
F12 ACK Proxy 1 -> NGW 1
ACK sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 ACK
Content-Length: 0
F13 480 Temporarily Unavailable F13 Proxy 1 -> User A
SIP/2.0 480 Temporarily Unavailable
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
;received=192.168.100.101
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
CSeq: 1 INVITE
Error-Info: <sip:temp-unavail-ann@ann.atlanta.com>
Content-Length: 0
F14 ACK User A -> Proxy 1
ACK sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Max-Forwards: 70
Via: SIP/2.0/UDP client.atlanta.com:5060;branch=z9hG4bK74bf9
From: BigGuy <sip:+13145551111@ss1.atlanta.com;user=phone>
;tag=9fxced76sl
To: LittleGuy <sip:+19725552222@ss1.atlanta.com;user=phone>
;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@atlanta.com
Johnston, et al. Informational [Page 131]
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CSeq: 1 ACK
Content-Length: 0
Johnston, et al. Informational [Page 132]
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5 Gateway to SIP Dialing
5.1 Success Scenarios
In these scenarios, User A is placing calls from the PSTN to User B
in a SIP network. User A's telephone switch signals to a Network
Gateway (NGW 1) using ANSI ISUP.
Since the called SIP User Agent does not send in-band signaling
information, no early media path needs to be established on the IP
side. As a result, the 183 Session Progress response is not used.
However, NGW 1 will establish a one way speech path prior to call
completion, and generate ringing for the PSTN caller. Any tones or
recordings are generated by NGW 1 and played in this speech path.
When the call completes successfully, NGW 1 bridges the PSTN speech
path with the IP media path.
To reduce the number of messages, only a single proxy server is shown
in these flows, which means that the atlanta.com proxy server has
access to the biloxi.com location service.
Johnston, et al. Informational [Page 133]
Internet Draft SIP Call Flow Examples July 2002
5.1.1 Successful PSTN to SIP call
Switch A NGW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | 180 F5 |
| | 180 F6 |<---------------|
| ACM F7 |<---------------| |
|<---------------| | |
| One Way Voice | | |
|<===============| | |
| Ringing Tone | | 200 F8 |
|<===============| 200 F9 |<---------------|
| |<---------------| |
| | ACK F10 | |
| ANM F12 |--------------->| ACK F11 |
|<---------------| |--------------->|
| Both Way Voice | Both Way RTP Media |
|<==============>|<===============================>|
| REL F13 | | |
|--------------->| | |
| RLC F14 | | |
|<---------------| BYE F15 | |
| |--------------->| BYE F16 |
| | |--------------->|
| | | 200 F17 |
| | 200 F18 |<---------------|
| |<---------------| |
| | | |
In this scenario, User A from the PSTN calls User B through a Network
Gateway NGW1 and Proxy Server Proxy 1. When User B answers the call
the media path is setup end-to-end. The call terminates when User A
hangs up the call, with User A's telephone switch sending an ISUP
RELease message which is mapped to a BYE by NGW 1.
Message Details
F1 IAM User A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
F2 INVITE A -> Proxy 1
Johnston, et al. Informational [Page 134]
Internet Draft SIP Call Flow Examples July 2002
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine where B is
located. Based upon location analysis the call is forwarded to NGW
1. NGW 1 prepares to receive data on port 3456 from User A.*/
F3 INVITE Proxy 1 -> User B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying User B -> Proxy 1
SIP/2.0 100 Trying
Johnston, et al. Informational [Page 135]
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Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 180 Ringing User B -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F6 180 Ringing Proxy 1 -> NGW 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F7 ACM NGW 1 -> User A
ACM
F8 200 OK User B -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Johnston, et al. Informational [Page 136]
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;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
Contact: <sip:UserB@192.168.200.201>
CSeq: 1 INVITE
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F9 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F10 ACK NGW 1 -> Proxy 1
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Johnston, et al. Informational [Page 137]
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Content-Length: 0
F11 ACK Proxy 1 -> User B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F12 ANM User B -> NGW 1
ANM
/* RTP streams are established between A and B (via the GW) */
/* User A Hangs Up with User B. */
F13 REL User A -> NGW 1
REL
CauseCode=16 Normal
F14 RLC NGW 1 -> User A
RLC
F15 BYE NGW 1-> Proxy 1
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F16 BYE Proxy 1 -> User B
Johnston, et al. Informational [Page 138]
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BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F17 200 OK User B -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F18 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
Johnston, et al. Informational [Page 139]
Internet Draft SIP Call Flow Examples July 2002
5.1.2 Successful PSTN to SIP call, Fast Answer
Switch A NGW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | 200 F5 |
| | 200 F6 |<---------------|
| |<---------------| |
| | ACK F7 | |
| ANM F9 |--------------->| ACK F8 |
|<---------------| |--------------->|
| Both Way Voice | Both Way RTP Media |
|<==============>|<===============================>|
| REL F10 | | |
|--------------->| | |
| RLC F11 | | |
|<---------------| BYE F12 | |
| |--------------->| BYE F13 |
| | |--------------->|
| | | 200 F14 |
| | 200 F15 |<---------------|
| |<---------------| |
| | | |
This "fast answer" scenario is similar to 5.1.1 except that User B
immediately accepts the call, sending a 200 OK (F5) without sending a
180 Ringing response. The Gateway then sends an Answer Message (ANM)
without sending an Address Complete Message (ACM). Note that for
ETSI and some other ISUP variants, a CONnect message (CON) would be
sent instead of the ANM.
Message Details
F1 IAM User A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
F2 INVITE NGW 1 -> Proxy 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Johnston, et al. Informational [Page 140]
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Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine where B is
located. Based upon location analysis the call is forwarded to User
B. User B prepares to receive data on port 3456 from User A.*/
F3 INVITE Proxy 1 -> User B
INVITE UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying Proxy 1 -> NGW 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
Johnston, et al. Informational [Page 141]
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CSeq: 1 INVITE
Content-Length: 0
F5 200 OK User B -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F6 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
Johnston, et al. Informational [Page 142]
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F7 ACK NGW 1 -> Proxy 1
ACK UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F8 ACK Proxy 1 -> User B
ACK UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=130.131.132.14
Max-Forwards: 69
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F9 ANM User B -> NGW 1
ANM
/* RTP streams are established between A and B (via the GW) */
/* User A Hangs Up with User B. */
F10 REL ser A -> NGW 1
REL
CauseCode=16 Normal
F11 RLC NGW 1 -> User A
RLC
F12 BYE NGW 1 -> Proxy 1
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
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Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F13 BYE Proxy 1 -> User B
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F14 200 OK User B -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F15 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
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5.1.3 Successful PBX to SIP call
PBX A GW 1 Proxy 1 User B
| | | |
| Seizure | | |
|--------------->| | |
| Wink | | |
|<---------------| | |
| MF Digits F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | 180 F5 |
| | 180 F6 |<---------------|
| |<---------------| |
| One Way Voice | | |
|<===============| | |
| Ringing Tone | | 200 F7 |
|<===============| 200 F8 |<---------------|
| |<---------------| |
| | ACK F9 | |
| Seizure |--------------->| ACK F10 |
|<---------------| |--------------->|
| Both Way Voice | Both Way RTP Media |
|<==============>|<===============================>|
| Seizure Removal| | |
|--------------->| | |
| Seizure Removal| | |
|<---------------| BYE F11 | |
| |--------------->| BYE F12 |
| | |--------------->|
| | | 200 F13 |
| | 200 F14 |<---------------|
| |<---------------| |
| | | |
In this scenario, User A dials from PBX A to User B through GW 1 and
Proxy 1. This is an example of a call that appears destined for the
PSTN but instead is routed to a SIP Client.
Signaling between PBX A and GW 1 is Feature Group B (FGB) circuit
associated signaling, in-band Mult-Frequency (MF) outpulsing. After
the receipt of the 180 Ringing from User B, GW 1 generates ringing
tone for User A.
User B answers the call by sending a 200 OK. The call terminates
when User A hangs up, causing GW1 to send a BYE.
The Gateway can only identify the trunk group that the
call came in on, it cannot identify the individual line on PBX A that
is placing the call. The SIP URI used to identify the caller is
Johnston, et al. Informational [Page 145]
Internet Draft SIP Call Flow Examples July 2002
shown in these flows as sip:551313@gw1.atlanta.com.
Message Details
PBX A -> GW 1
Seizure
GW 1 -> PBX A
Wink
F1 MF Digits PBX A -> GW 1
KP 1 972 555 2222 ST
F2 INVITE GW 1 -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
Max-Forwards: 70
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:551313@gw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine where the
phone number +19725552222 is located. Based upon location
analysis the call is forwarded to SIP User B. */
F3 INVITE Proxy 1 -> User B
INVITE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
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Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:551313@gw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying Proxy 1 -> GW 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 180 Ringing User B -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F6 180 Ringing Proxy 1 -> GW 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
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Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
/* One way Voice path is established between GW and the PBX for
ringing. */
F7 200 OK User B -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
Contact: <sip:UserB@192.168.200.201>
CSeq: 1 INVITE
Content-Type: application/sdp
Content-Length: 145
v=0
o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F8 200 OK Proxy 1 -> GW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Type: application/sdp
Content-Length: 145
v=0
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o=UserB 2890844527 2890844527 IN IP4 client.biloxi.com
s=-
c=IN IP4 192.168.200.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F9 ACK GW 1 -> Proxy 1
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F10 ACK Proxy 1 -> User B
ACK sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Max-Forwards: 69
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* RTP streams are established between A and B (via the GW) */
/* User A Hangs Up with User B. */
F11 BYE GW 1 -> Proxy 1
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
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F12 BYE Proxy 1 -> User B
BYE sip:UserB@192.168.200.201 SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Max-Forwards: 69
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F13 200 OK User B -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
F14 200 OK Proxy 1 -> GW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
From: <sip:551313@gw1.atlanta.com;user=phone>;tag=jwdkallkzm
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 2 BYE
Content-Length: 0
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5.2 Failure Scenarios
5.2.1 Unsuccessful PSTN to SIP REL, SIP error mapped to REL
Switch A GW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| |
| | 604 F3 | |
| |<---------------| |
| | ACK F4 | |
| |--------------->| |
| REL F5 | | |
|<---------------| | |
| RLC F6 | | |
|--------------->| | |
| | | |
User A attempts to place a call through Gateway GW 1 and Proxy 1,
which is unable to find any routing for the number. The call is
rejected by Proxy 1 with a REL message containing a specific Cause
value mapped by the gateway based on the SIP error.
Message Details
F1 IAM User A -> GW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-9999,NPI=E.164,NOA=National
F2 INVITE A -> Proxy 1
INVITE sip:+1972559999@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@gw1.atlanta.com;user=phone>;tag=076342s
To: <sip:+1972559999@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@gw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 140
v=0
o=GW 2890844527 2890844527 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
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m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service to find a route to +1-972-555-
9999. A route is not found, so Proxy 1 rejects the call. */
F3 604 Does Not Exist Anywhere Proxy 1 -> GW 1
SIP/2.0 604 Does Not Exist Anywhere
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:+13145551111@gw1.atlanta.com;user=phone>;tag=076342s
To: <sip:+1972559999@ss1.atlanta.com;user=phone>;tag=6a34d410
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 INVITE
Error-Info: <sip:does-not-exist@ann.atlanta.com>
Content-Length: 0
F4 ACK GW 1 -> Proxy 1
ACK sip:+1972559999@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@gw1.atlanta.com;user=phone>;tag=076342s
To: <sip:+1972559999@ss1.atlanta.com;user=phone>;tag=6a34d410
Call-ID: 4Fde34wkd11wsGFDs3@gw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F5 REL GW 1 -> User A
REL
CauseCode=1
F6 RLC User A -> GW 1
RLC
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5.2.2 Unsuccessful PSTN to SIP REL, SIP busy mapped to REL
Switch A NGW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | 600 F5 |
| | |<---------------|
| | | ACK F6 |
| | 600 F7 |--------------->|
| |<---------------| |
| | ACK F8 | |
| |--------------->| |
| REL(17) F9 | | |
|<---------------| | |
| RLC F10 | | |
|<-------------->| | |
| | | |
In this scenario, User A calls User B through Network Gateway NGW 1
and Proxy 1. The call is routed to User B by Proxy 1. The call is
rejected by User B who sends a 600 Busy Everywhere response. The
Gateway sends a REL message containing a specific Cause value mapped
by the gateway based on the SIP error.
Since no interworking is indicated in the IAM (F1), the busy tone is
generated locally by User A's telephone switch. In scenario 5.2.3,
the busy signal is generated by the Gateway since interworking is
indicated. For more discussion on interworking, refer to [SIP-ISUP].
Message Details
F1 IAM User A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
F2 INVITE A -> Proxy 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
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CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 140
v=0
o=GW 2890844527 2890844527 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine a route for
+19725552222. The call is then forwarded to User B. */
F3 INVITE F3 Proxy 1 -> User B
INVITE UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 140
v=0
o=GW 2890844527 2890844527 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying Proxy 1 -> NGW 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
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F5 600 Busy Everywhere User B -> Proxy 1
SIP/2.0 600 Busy Everywhere
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 ACK Proxy 1 -> User B
ACK UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F7 600 Busy Everywhere Proxy 1 -> NGW 1
SIP/2.0 600 Busy Everywhere
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F8 ACK NGW 1 -> Proxy 1
ACK UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
Johnston, et al. Informational [Page 155]
Internet Draft SIP Call Flow Examples July 2002
F9 REL NGW 1 -> User A
REL
CauseCode=17 Busy
F10 RLC User A -> NGW 1
RLC
Johnston, et al. Informational [Page 156]
Internet Draft SIP Call Flow Examples July 2002
5.2.3 Unsuccessful PSTN->SIP, SIP error interworking to tones
Switch A NGW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | 600 F5 |
| | |<---------------|
| | | ACK F6 |
| | 600 F7 |--------------->|
| |<---------------| |
| | ACK F8 | |
| ACM F9 |--------------->| |
|<---------------| | |
| One Way Voice | | |
|<===============| | |
| Busy Tone | | |
|<===============| | |
| REL(16) F10 | | |
|--------------->| | |
| RLC F11 | | |
|<---------------| | |
| | | |
In this scenario, User A calls User B through Network Gateway NGW1
and Proxy 1. The call is routed to User B by Proxy 1. The call is
rejected by the User B client. NGW 1 sets up a two way voice path to
User A and plays busy tone. The caller then disconnects
NGW 1 plays the busy tone since the IAM (F1) indicates the
interworking is present. In scenario 5.2.2, with no interworking,
the busy indication is carried in the REL Cause value and is
generated locally instead.
Again, note that for ETSI or ITU ISUP, a CONnect message would be
sent instead of the Answer Message.
Message Details
F1 IAM User A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
Interworking=encountered
Johnston, et al. Informational [Page 157]
Internet Draft SIP Call Flow Examples July 2002
F2 INVITE NGW1 -> Proxy 1
INVITE sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine a route for
+19725552222. The call is then forwarded to User B. */
F3 INVITE Proxy 1 -> User B
INVITE UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying User B -> Proxy 1
Johnston, et al. Informational [Page 158]
Internet Draft SIP Call Flow Examples July 2002
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 600 Busy Everywhere User B -> Proxy 1
SIP/2.0 600 Busy Everywhere
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F6 ACK Proxy 1 -> User B
ACK UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F7 600 Busy Everywhere Proxy 1 -> NGW 1
SIP/2.0 600 Busy Everywhere
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F8 ACK NGW 1 -> Proxy 1
Johnston, et al. Informational [Page 159]
Internet Draft SIP Call Flow Examples July 2002
ACK sip:+19725552222@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F9 ACM NGW 1 -> User A
ACM
/* A one way speech path is established between NGW 1 and User A. */
/* Call Released after User A hangs up. */
F10 REL User A -> NGW 1
REL
CauseCode=16
F11 RLC NGW 1 -> User A
RLC
Johnston, et al. Informational [Page 160]
Internet Draft SIP Call Flow Examples July 2002
5.2.4 Unsuccessful PSTN->SIP, ACM timeout
Switch A NGW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | INVITE F5 |
| | |--------------->|
| | | INVITE F6 |
| | |--------------->|
| | | INVITE F7 |
| | |--------------->|
| | | INVITE F8 |
| | |--------------->|
| | | INVITE F9 |
| | |--------------->|
| REL F10 | | |
|--------------->| | |
| RLC F11 | | |
|<---------------| | |
| | CANCEL F12 | |
| |--------------->| |
| | 200 F13 | |
| |<---------------| |
User A calls User B through NGW 1 and Proxy 1. Proxy 1 re-sends the
INVITE after the expiration of SIP timer T1 without receiving any
response from User B. User B never responds with 180 Ringing or any
other response (it is reachable but unresponsive). After the
expiration of a timer, User A's network disconnects the call by
sending a Release message REL. The Gateway maps this to a CANCEL.
Message Details
F1 IAM User A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
F2 INVITE A -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Johnston, et al. Informational [Page 161]
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Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine a route for
+19725552222. The call is then forwarded to User B. */
F3 INVITE Proxy 1 -> User B
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
c c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying Proxy 1 -> NGW 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 INVITE Proxy 1 -> User B
Johnston, et al. Informational [Page 162]
Internet Draft SIP Call Flow Examples July 2002
Same as Message F3
F6 INVITE Proxy 1 -> User B
Same as Message F3
F7 INVITE Proxy 1 -> User B
Same as Message F3
F8 INVITE Proxy 1 -> User B
Same as Message F3
F9 INVITE Proxy 1 -> User B
Same as Message F3
/* Timer expires in User A's access network. */
F10 REL User A -> NGW 1
REL
CauseCode=16 Normal
F11 RLC NGW 1 -> User A
RLC
F12 CANCEL NGW 1 -> Proxy 1
CANCEL sip:+19725552222@ss11.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F13 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Johnston, et al. Informational [Page 163]
Internet Draft SIP Call Flow Examples July 2002
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
Johnston, et al. Informational [Page 164]
Internet Draft SIP Call Flow Examples July 2002
5.2.5 Unsuccessful PSTN->SIP, ACM timeout, stateless Proxy
Switch A NGW 1 Stateless Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | INVITE F4 |--------------->|
| |--------------->| INVITE F5 |
| | INVITE F6 |--------------->|
| |--------------->| INVITE F7 |
| | INVITE F8 |--------------->|
| |--------------->| INVITE F9 |
| | INVITE F10 |--------------->|
| |--------------->| INVITE F11 |
| | INVITE F12 |--------------->|
| |--------------->| INVITE F13 |
| | |--------------->|
| REL F14 | | |
|--------------->| | |
| RLC F15 | | |
|<---------------| | |
In this scenario, User A calls User B through NGW 1 and Proxy 1.
Since Proxy 1 is stateless (it does not send a 100 Trying response),
NGW 1 re-sends the INVITE message after the expiration of
SIP timer T1. User B does not respond with 180 Ringing. User A's
network disconnects the call with a release REL (CauseCode=102
Timeout).
Message Details
F1 IAM User A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
F2 INVITE NGW 1 -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Johnston, et al. Informational [Page 165]
Internet Draft SIP Call Flow Examples July 2002
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine a route for
+19725552222. The call is then forwarded to User B. */
F3 INVITE Proxy 1 -> User B
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
Max-Forwards: 69
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 INVITE NGW 1 -> Proxy 1
Same as Message F2
F5 INVITE Proxy 1 -> User B
Same as Message F3
F6 INVITE NGW 1 -> Proxy 1
Same as Message F2
Johnston, et al. Informational [Page 166]
Internet Draft SIP Call Flow Examples July 2002
F7 INVITE Proxy 1 -> User B
Same as Message F3
F8 INVITE NGW 1 -> Proxy 1
Same as Message F2
F9 INVITE Proxy 1 -> User B
Same as Message F3
F10 INVITE NGW 1 -> Proxy 1
Same as Message F2
F11 INVITE Proxy 1 -> User B
Same as Message F3
F12 INVITE NGW 1 -> Proxy 1
Same as Message F2
F13 INVITE Proxy 1 -> User B
Same as Message F3
/* A timer expires in User A's access network. */
F14 REL User A -> NGW 1
REL
CauseCode=102 Timeout
F15 RLC NGW 1 -> User A
RLC
Johnston, et al. Informational [Page 167]
Internet Draft SIP Call Flow Examples July 2002
5.2.6 Unsuccessful PSTN->SIP, Caller Abandonment
Switch A NGW 1 Proxy 1 User B
| | | |
| IAM F1 | | |
|--------------->| INVITE F2 | |
| |--------------->| INVITE F3 |
| | 100 F4 |--------------->|
| |<---------------| |
| | | 180 F5 |
| | 180 F6 |<---------------|
| ACM F7 |<---------------| |
|<---------------| | |
| One Way Voice | | |
|<===============| | |
| Ringing Tone | | |
|<===============| | |
| | | |
| REL F8 | | |
|--------------->| | |
| RLC F9 | | |
|<---------------| CANCEL F10 | |
| |--------------->| |
| | 200 F11 | |
| |<---------------| |
| | | CANCEL F12 |
| | |--------------->|
| | | 200 F13 |
| | |<---------------|
| | | 487 F14 |
| | |<---------------|
| | | ACK F15 |
| | 487 F16 |--------------->|
| |<---------------| |
| | ACK F17 | |
| |--------------->| |
| | | |
In this scenario, User A calls User B through NGW 1 and Proxy 1.
User B does not respond with 200 OK. NGW 1 plays ringing tone since
the ACM indicates that interworking has been encountered. User A
disconnects the call with a Release message REL which is mapped by
NGW 1 to a CANCEL. Note that if User B had sent a 200 OK response
after the REL, NGW 1 would have sent an ACK then a BYE to properly
terminate the call.
Message Details
F1 IAM User A -> NGW 1
Johnston, et al. Informational [Page 168]
Internet Draft SIP Call Flow Examples July 2002
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=972-555-2222,NPI=E.164,NOA=National
F2 INVITE A -> Proxy 1
INVITE sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine a route for
+19725552222. The call is then forwarded to User B. */
F3 INVITE Proxy 1 -> User B
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844527 2890844527 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
Johnston, et al. Informational [Page 169]
Internet Draft SIP Call Flow Examples July 2002
m=audio 3456 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 100 Trying User B -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.201
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 180 Ringing User B -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F6 180 Ringing Proxy 1 -> NGW 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:UserB@192.168.200.201>
Content-Length: 0
F7 ACM NGW 1 -> User A
ACM
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/* User A hangs up */
F8 REL User A -> NGW 1
REL
CauseCode=16 Normal
F9 RLC NGW 1 -> User A
RLC
F10 CANCEL NGW 1 -> Proxy 1
CANCEL sip:+19725552222@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F11 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F12 CANCEL Proxy 1 -> User B
CANCEL sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F13 200 OK User B -> Proxy 1
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SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 CANCEL
Content-Length: 0
F14 487 Request Terminated User B -> Proxy 1
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F15 ACK Proxy 1 -> User B
ACK sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F16 487 Request Terminated Proxy 1 -> NGW 1
SIP/2.0 487 Request Terminated
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F17 ACK NGW 1 -> Proxy 1
ACK sip:+19725552222@ss11.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
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Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19725552222@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 4Fde34wkd11wsGFDs3@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
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6 Gateway to Gateway Dialing via SIP Network
In these scenarios, both the caller and the called party are in the
telephone network, either normal PSTN subscribers or PBX extensions.
The calls route through two Gateways and at least one SIP Proxy
Server. The Proxy Server performs the authentication and location of
the Gateways.
Again it is noted that the intent of this call flows document is not
to provide a detailed parameter level mapping of SIP to PSTN
protocols. For information on SIP to ISUP mapping, the reader is
referred to other references [SIP-ISUP].
6.1 Success Scenarios
In these scenarios, the call is successfully completed between the
two Gateways allowing the PSTN or PBX users to communicate. The 183
Session Progress response is used to indicate in-band alerting may
flow from the called party telephone switch to the caller.
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6.1.1 Successful ISUP PSTN to ISUP PSTN call
Switch A NGW 1 Proxy 1 GW 2 Switch C
| | | | |
| IAM F1 | | | |
|------------->| | | |
| | INVITE F2 | | |
| |------------->| INVITE F3 | |
| | |------------->| IAM F4 |
| | | |------------->|
| | | | ACM F5 |
| | | 183 F6 |<-------------|
| | 183 F7 |<-------------| |
| ACM F8 |<-------------| | |
|<-------------| | | |
| One Way Voice| Two Way RTP Media | One Way Voice|
|<=============|<===========================>|<=============|
| | | | ANM F9 |
| | | 200 F10 |<-------------|
| | 200 F11 |<-------------| |
| ANM F12 |<-------------| | |
|<-------------| | | |
| | ACK F13 | | |
| |------------->| ACK F14 | |
| | |------------->| |
|Both Way Voice| Both Way RTP Media |Both Way Voice|
|<=============|<===========================>|<=============|
| | | | REL F15 |
| | | |<-------------|
| | | BYE F16 | |
| | BYE F18 |<-------------| RLC F17 |
| |<-------------| |------------->|
| | | | |
| | 200 F19 | | |
| |------------->| 200 F20 | |
| | |------------->| |
| REL F21 | | | |
|<-------------| | | |
| RLC F22 | | | |
|------------->| | | |
| | | | |
In this scenario, User A in the PSTN calls User C who is an extension
on a PBX. User A's telephone switch signals via SS7 to the Network
Gateway NGW 1, while User C's PBX signals via SS7 with the
Gateway GW 2. The CdPN and CgPN are mapped by GW1 into SIP URIs and
placed in the To and From headers. Proxy 1 looks up the dialed
digits in the Request-URI and maps the digits to the PBX extension of
User C which is served by GW 2. The Proxy in F3 uses the host
portion of the Request-URI to identify what private dialing plan is
being referenced. The INVITE is then forwarded to GW 2 for call
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completion. An early media path is established end-to-end so that
User A can hear the ringing tone generated by PBX C.
User C answers the call and the media path is cut through in both
directions. User B hangs up terminating the call.
Message Details
F1 IAM Switch A -> NGW 1
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=918-555-3333,NPI=E.164,NOA=National
F2 INVITE NGW 1 -> Proxy 1
INVITE sip:+19185553333@ss1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844526 2890844526 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 consults Location Service and translates the dialed number
to a private number in the Request-URI*/
F3 INVITE Proxy 1 -> GW 2
INVITE sip:4443333@gw2.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.101
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
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CSeq: 1 INVITE
Contact: <sip:+13145551111@ngw1.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844526 2890844526 IN IP4 ngw1.atlanta.com
s=-
c=IN IP4 192.168.255.101
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 IAM GW 2 -> Switch C
IAM
CgPN=314-555-1111,NPI=E.164,NOA=National
CdPN=444-3333,NPI=Private,NOA=Subscriber
F5 ACM Switch C -> GW 2
ACM
/* Based on the ACM message, GW 2 returns a 183 response. In-band
call progress indications are sent to User A through NGW 1. */
F6 183 Session Progress GW 2 -> Proxy 1
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:4443333@gw2.atlanta.com>
Content-Type: application/sdp
Content-Length: 149
v=0
o=GW 987654321 987654321 IN IP4 gw2.atlanta.com
s=-
c=IN IP4 192.168.255.202
t=0 0
m=audio 14918 RTP/AVP 0
a=rtpmap:0 PCMU/8000
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F7 183 Session Progress Proxy 1 -> GW 1
SIP/2.0 183 Session Progress
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:4443333@gw2.atlanta.com>
Content-Type: application/sdp
Content-Length: 149
v=0
o=GW 987654321 987654321 IN IP4 gw2.atlanta.com
s=-
c=IN IP4 192.168.255.202
t=0 0
m=audio 14918 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* NGW 1 receives packets from GW 2 with encoded ringback, tones or
other audio. NGW 1 decodes this and places it on the originating
trunk. */
F8 ACM NGW 1 -> Switch A
ACM
/* User B answers */
F9 ANM Switch C -> GW 2
ANM
F10 200 OK GW 2 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
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CSeq: 1 INVITE
Contact: <sip:4443333@gw2.atlanta.com>
Content-Type: application/sdp
Content-Length: 149
v=0
o=GW 987654321 987654321 IN IP4 gw2.atlanta.com
s=-
c=IN IP4 192.168.255.202
t=0 0
m=audio 14918 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F11 200 OK Proxy 1 -> NGW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:4443333@gw2.atlanta.com>
Content-Type: application/sdp
Content-Length: 149
v=0
o=GW 987654321 987654321 IN IP4 gw2.atlanta.com
s=-
c=IN IP4 192.168.255.202
t=0 0
m=audio 14918 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F12 ANM NGW 1 -> Switch A
ANM
F13 ACK NGW 1 -> Proxy 1
ACK sip:4443333@gw2.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
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CSeq: 1 ACK
Content-Length: 0
F14 ACK Proxy 1 -> GW 2
ACK sip:4443333@gw2.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP ngw1.atlanta.com:5060;branch=z9hG4bKlueha2
;received=192.168.255.101
Max-Forwards: 69
From: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
To: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
/* RTP streams are established between NGW 1 and GW 2. */
/* User B Hangs Up with User A. */
F15 REL Switch C -> GW 2
REL
CauseCode=16 Normal
F16 BYE GW 2 -> Proxy 1
BYE sip:+13145551111@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP gw2.atlanta.com:5060;branch=z9hG4bKtexx6
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
To: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 4 BYE
Content-Length: 0
F17 RLC GW 2 -> Switch C
RLC
F18 BYE Proxy 1 -> NGW 1
BYE sip:+13145551111@ngw1.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP gw2.atlanta.com:5060;branch=z9hG4bKtexx6
;received=192.168.255.202
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Max-Forwards: 69
From: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
To: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 4 BYE
Content-Length: 0
F19 200 OK NGW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP gw2.atlanta.com:5060;branch=z9hG4bKtexx6
;received=192.168.255.202
From: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
To: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 4 BYE
Content-Length: 0
F20 200 OK Proxy 1 -> GW 2
SIP/2.0 200 OK
Via: SIP/2.0/UDP gw2.atlanta.com:5060;branch=z9hG4bKtexx6
;received=192.168.255.202
From: <sip:+19185553333@ss1.atlanta.com;user=phone>;tag=314159
To: <sip:+13145551111@ngw1.atlanta.com;user=phone>;tag=7643kals
Call-ID: 2xTb9vxSit55XU7p8@ngw1.atlanta.com
CSeq: 4 BYE
Content-Length: 0
F21 REL Switch C -> GW 2
REL
CauseCode=16 Normal
F22 RLC GW 2 -> Switch C
RLC
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6.1.2 Successful FGB PBX to ISDN PBX call with overflow
PBX A GW 1 Proxy 1 GW 2 GW 3 PBX C
| | | | | |
| Seizure | | | | |
|----------->| | | | |
| Wink | | | | |
|<-----------| | | | |
|MF Digits F1| | | | |
|----------->| | | | |
| | INVITE F2 | | | |
| |----------->| INVITE F3 | | |
| | |----------->| | |
| | | 503 F4 | | |
| | |<-----------| | |
| | | ACK F5 | | |
| | |----------->| | |
| | | INVITE F6 | |
| | |------------------------>| SETUP F7 |
| | | 100 F8 |----------->|
| | |<------------------------|CALL PROC F9|
| | | |<-----------|
| | | | ALERT F10 |
| | | 180 F11 |<-----------|
| | 180 F12 |<------------------------| |
| |<-----------| | |
| Ringtone | | |OneWay Voice|
|<===========| | |<===========|
| | | | CONNect F13|
| | | 200 F14 |<-----------|
| | 200 F15 |<------------------------| |
| Seizure |<-----------| | |
|<-----------| ACK F16 | | |
| |----------->| ACK F17 | |
| | |------------------------>|CONN ACK F18|
| | | |----------->|
|BothWayVoice| Both Way RTP Media |BothWayVoice|
|<==========>|<====================================>|<==========>|
| | | | DISC F19 |
| | | |<-----------|
| | | BYE F20 | |
| | BYE F21 |<------------------------| REL F22 |
|Seiz Removal|<-----------| |----------->|
|<-----------| 200 F23 | | |
|Seiz Removal|----------->| 200 F24 | |
|----------->| |------------------------>| REL COM F25|
| | | |<-----------|
| | | | |
PBX User A calls PBX User C via Gateway GW 1 and Proxy 1. During the
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attempt to reach User C via GW 2, an error is encountered - Proxy 1
receives a 503 Service Unavailable (F4) response to the forwarded
INVITE. This could be due to all circuits being busy, or some other
outage at GW 2. Proxy 1 recognizes the error and uses an alternative
route via GW 3 to terminate the call. From there, the call proceeds
normally with User C answering the call. The call is terminated when
User C hangs up.
Message Details
PBX A -> GW 1
Seizure
GW 1 -> PBX A
Wink
F1 MF Digits PBX A -> GW 1
KP 444 3333 ST
F2 INVITE GW 1 -> Proxy 1
INVITE sip:4443333@ss1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
Max-Forwards: 70
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:551313@gw1.atlanta.com>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844526 2890844526 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
/* Proxy 1 uses a Location Service function to determine where B is
located. Response is returned listing alternative routes, GW2 and
GW3, which are then tried sequentially. */
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F3 INVITE Proxy 1 -> GW 2
INVITE sip:4443333@gw2.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:551313@gw1.atlanta.com>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844526 2890844526 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F4 503 Service Unavailable GW 2 -> Proxy 1
SIP/2.0 503 Service Unavailable
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
;received=192.168.255.111
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
F5 ACK Proxy 1 -> GW 2
ACK sip:4443333@ss1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.1
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Max-Forward: 70
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=314159
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
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F6 INVITE Proxy 1 -> GW 3
INVITE sip:+19185553333@gw3.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Max-Forwards: 69
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:551313@gw1.atlanta.com>
Content-Type: application/sdp
Content-Length: 141
v=0
o=GW 2890844526 2890844526 IN IP4 gw1.atlanta.com
s=-
c=IN IP4 192.168.255.201
t=0 0
m=audio 49172 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F7 SETUP GW 3 -> PBX C
Protocol discriminator=Q.931
Message type=SETUP
Bearer capability: Information transfer capability=0 (Speech) or 16
(3.1 kHz audio)
Channel identification=Preferred or exclusive B-channel
Progress indicator=1 (Call is not end-to-end ISDN; further call
progress information may be available inband)
Called party number:
Type of number and numbering plan ID=33 (National number in ISDN
numbering plan)
Digits=918-555-3333
F8 100 Trying GW 3 -> Proxy 1
SIP/2.0 100 Trying
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Content-Length: 0
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F9 CALL PROCeeding PBX C -> GW 3
Protocol discriminator=Q.931
Message type=CALL PROC
F10 ALERT PBX C -> GW 3
Protocol discriminator=Q.931
Message type=PROG
/* Based on ALERT message, GW 3 returns a 180 response. */
F11 180 Ringing GW 3 -> Proxy 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
;received=192.168.255.111
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19185553333@gw3.atlanta.com;user=phone>
Content-Length: 0
F12 180 Ringing Proxy 1 -> GW 1
SIP/2.0 180 Ringing
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19185553333@gw3.atlanta.com;user=phone>
Content-Length: 0
F13 CONNect PBX C -> GW 3
Protocol discriminator=Q.931
Message type=CONN
F14 200 OK GW 3 -> Proxy 1
Johnston, et al. Informational [Page 186]
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SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
;received=192.168.255.111
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19185553333@gw3.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 149
v=0
o=GW 987654321 987654321 IN IP4 gw3.atlanta.com
s=-
c=IN IP4 192.168.255.203
t=0 0
m=audio 14918 RTP/AVP 0
a=rtpmap:0 PCMU/8000
F15 200 OK Proxy 1 -> GW 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Record-Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 INVITE
Contact: <sip:+19185553333@gw3.atlanta.com;user=phone>
Content-Type: application/sdp
Content-Length: 149
v=0
o=GW 987654321 987654321 IN IP4 gw3.atlanta.com
s=-
c=IN IP4 192.168.255.203
t=0 0
m=audio 14918 RTP/AVP 0
a=rtpmap:0 PCMU/8000
GW 1 -> PBX A
Seizure
Johnston, et al. Informational [Page 187]
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F16 ACK GW 1 -> Proxy 1
ACK sip:+19185553333@gw3.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F17 ACK Proxy 1 -> GW 3
ACK sip:+19185553333@gw3.atlanta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
Via: SIP/2.0/UDP gw1.atlanta.com:5060;branch=z9hG4bKwqwee65
;received=192.168.255.201
Max-Forwards: 69
From: <sip:551313@gw1.atlanta.com>;tag=63412s
To: <sip:4443333@ss1.atlanta.com>;tag=123456789
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 ACK
Content-Length: 0
F18 CONNect ACK GW 3 -> PBX C
Protocol discriminator=Q.931
Message type=CONN ACK
/* RTP streams are established between GW 1 and GW 3. */
/* User B Hangs Up with User A. */
F19 DISConnect PBX C -> GW 3
Protocol discriminator=Q.931
Message type=DISC
Cause=16 (Normal clearing)
F20 BYE GW 3 -> Proxy 1
BYE sip:551313@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP gw3.atlanta.com:5060;branch=z9hG4bKkdjuwq
Max-Forwards: 70
Route: <sip:ss1.atlanta.com;lr>
From: <sip:4443333@ss1.atlanta.com>;tag=123456789
To: <sip:551313@gw1.atlanta.com>;tag=63412s
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Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 BYE
Content-Length: 0
F21 BYE Proxy 1 -> GW 1
BYE sip:551313@gw1.atlanta.com SIP/2.0
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
Via: SIP/2.0/UDP gw3.atlanta.com:5060;branch=z9hG4bKkdjuwq
;received=192.168.255.203
Max-Forwards: 69
From: <sip:4443333@ss1.atlanta.com>;tag=123456789
To: <sip:551313@gw1.atlanta.com>;tag=63412s
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 BYE
Content-Length: 0
GW 1 -> PBX A
Seizure removal
F22 RELease GW 3 -> PBX C
Protocol discriminator=Q.931
Message type=REL
F23 200 OK GW 1 -> Proxy 1
SIP/2.0 200 OK
Via: SIP/2.0/UDP ss1.atlanta.com:5060;branch=z9hG4bK2d4790.2
;received=192.168.255.111
Via: SIP/2.0/UDP gw3.atlanta.com:5060;branch=z9hG4bKkdjuwq
;received=192.168.255.203
From: <sip:4443333@ss1.atlanta.com>;tag=123456789
To: <sip:551313@gw1.atlanta.com>;tag=63412s
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
CSeq: 1 BYE
Content-Length: 0
F24 200 OK Proxy 1 -> GW 3
SIP/2.0 200 OK
Via: SIP/2.0/UDP gw3.atlanta.com:5060;branch=z9hG4bKkdjuwq
;received=192.168.255.203
From: <sip:4443333@ss1.atlanta.com>;tag=123456789
To: <sip:551313@gw1.atlanta.com>;tag=63412s
Call-ID: 2xTb9vxSit55XU7p8@gw1.atlanta.com
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CSeq: 1 BYE
Content-Length: 0
F25 RELease COMplete PBX C -> GW 3
Protocol discriminator=Q.931
Message type=REL COM
PBX A -> GW 1
Seizure removal
Johnston, et al. Informational [Page 190]
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7 SIP Test Messages
The files in here are test messages for SIP servers to exercise
various functions. They have been used in SIPit
interoperablity events. All messages shown here are valid, unless
otherwise noted. The correct behavior of servers and clients is also
described.
7.1 INVITE Parser Torture Test Message
This message is a correctly formatting SIP message. It contains:
line folding all over
escaped characters within quotes
LWS between colons, semicolons, headers, and other fields
both comma separated and separate listing of headers
mix or short and long form for the same header
unknown header field
unusual header ordering
unknown parameters of a known header
Proxies should forward message and clients should respond as to a
normal INVITE message.
Message Details
INVITE sip:vivekg@chair.dnrc.bell-labs.com SIP/2.0
TO :
sip:vivekg@chair.dnrc.bell-labs.com ; tag = 1918181833n
From : "J Rosenberg \\\"" <sip:jdrosen@lucent.com>
;
tag = 98asjd8
Max-Forwards: 6
Call-ID
: 0ha0isndaksdj@10.1.1.1
cseq: 8
INVITE
Via : SIP / 2.0
/UDP
135.180.130.133;branch=z9hG4bKkdjuw
Subject :
NewFangledHeader: newfangled value
more newfangled value
Content-Type: application/sdp
v: SIP / 2.0 / TCP 1192.168.156.222 ;
branch = 9ikj8 ,
SIP / 2.0 / UDP 192.168.255.111 ; hidden
m:"Quoted string \"\"" <sip:jdrosen@bell-labs.com> ; newparam =
newvalue ;
secondparam = secondvalue ; q = 0.33,
tel:4443322
Johnston, et al. Informational [Page 191]
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v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.2 INVITE with Proxy-Require and Require
This message tests support for Proxy-Require and Require. It is a
request that contains both headers, listing new features.
Proxies and clients should respond with a 420 Bad Extension, and an
Unsupported header listing these features.
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:j_user@company.com
From: sip:caller@university.edu;tag=242etr
Max-Forward: 6
Call-ID: 0ha0isndaksdj@10.1.1.1
Require: newfeature1, newfeature2
Proxy-Require: newfeature3, newfeature4
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
7.3 INVITE with Unknown Schemes in URIs
This message contains unknown schemes in the Request URI, To, From
and Contact headers of a request.
A server should probably return a not found error; but other
behaviors are acceptable.
Message Details
INVITE name:John_Smith SIP/2.0
To: isbn:2983792873
From: <http://www.cs.columbia.edu>;tag=3234233
Call-ID: 0ha0isndaksdj@10.1.2.3
CSeq: 8 INVITE
Max-Forward: 7
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Johnston, et al. Informational [Page 192]
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v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.4 REGISTER with Y2038 Test
This message is a registration request with an expiration year of
2040. This makes sure that a server doesn't crash on seeing a date
past Y2038.
The correct behavior is probably to limit the lifetime to some
configured maximum.
Message Details
REGISTER sip:company.com SIP/2.0
To: sip:user@company.com
From: sip:user@company.com;tag=3411345
Max-Forwards: 8
Contact: sip:user@host.company.com
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 REGISTER
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Expires: Sat, 01 Dec 2040 16:00:00 GMT
7.5 INVITE with inconsistent Accept and message body
This is a UAS test. It is a request that includes an Accept header
without SDP. The UAS should respond with an error.
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:j_user@company.com
From: sip:caller@university.edu;tag=234
Max-Forwards: 5
Call-ID: 0ha0isndaksdj@10.0.0.1
Accept: text/newformat
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
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v=0
c=IN IP4 135.180.130.88
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.6 INVITE with non-SDP message body
This is a test of a user agent server. It is a request that includes
a body of a non-SDP type.
The user agent server should respond with an error.
Message Details
INVITE sip:user@comapny.com SIP/2.0
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=8
Max-Forwards: 70
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/newformat
<audio>
<pcmu port="443"/>
</audio>
7.7 Unknown Method Message
This request message contains a new unknown method, NEWMETHOD.
A proxy should forward this using the same retransmission rules as
BYE. A UAS should reject it with an error, and list the available
methods in the response.
Message Details
NEWMETHOD sip:user@comapny.com SIP/2.0
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=34525
Max-Forwards: 6
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 NEWMETHOD
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
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v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
c=IN IP4 135.180.130.88
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.8 Unknown Method with CSeq Error
This message is nearly identical to the Unknown Method message. It is
a request with a new unknown method, but with a CSeq method tag which
does not match.
A proxy should either respond with an error, or correct the method
tag. The user agent should reject it with an error, and list the
available methods in the response.
Message Details
NEWMETHOD sip:user@comapny.com SIP/2.0
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=23411413
Max-Forwards: 3
Call-ID: 0ha0isndaksdj@10.0.1.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.9 REGISTER with Unknown Authorization Scheme
This message is a REGISTER request with an unknown authorization
scheme.
The server should do something reasonable, such as rejecting the
request.
Johnston, et al. Informational [Page 195]
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Message Details
REGISTER sip:company.com SIP/2.0
To: sip:j.user@company.com
From: sip:j.user@company.com;tag=87321hj23128
Max-Forwards: 8
Call-ID: 0ha0isndaksdj@10.0.1.1
CSeq: 8 REGISTER
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Authorization: Super-PGP ajsohdaosdh0asyhdaind08yasdknasd09asidhas0d8
7.10 Multiple SIP Request in a Single Message
This message contains two requests, separated by a bunch of
whitespace. Since the message exceeds the length indicated in the
Content-Length header, the message should be rejected. (Multiple SIP
requests per UDP packet are no longer allowed.)
Message Details
REGISTER sip:company.com SIP/2.0
To: sip:j.user@company.com
From: sip:j.user@company.com;tag=43251j3j324
Max-Forwards: 8
Call-ID: 0ha0isndaksdj@10.0.2.2
Contact: sip:j.user@host.company.com
CSeq: 8 REGISTER
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Length: 0
INVITE sip:joe@company.com SIP/2.0
To: sip:joe@company.com
From: sip:caller@university.edu;tag=141334
Max-Forwards: 8
Call-ID: 0ha0isnda977644900765@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m =video 3227 RTP/AVP 31
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a=rtpmap:31 LPC
7.11 INVITE missing Required Headers
This message contains no Call-ID, From, or To header.
The server should not crash, and ideally should respond with an
error.
Message Details
INVITE sip:user@company.com SIP/2.0
CSeq: 0 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.12 INVITE with Duplicate Required Headers
The message contains a request with an extra Call-ID and To field.
The server should not crash, and should ideally respond with an
error.
Message Details
INVITE sip:user@company.com SIP/2.0
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Max-Forwards: 70
CSeq: 0 INVITE
Call-ID: 98asdh@10.1.1.1
Call-ID: 98asdh@10.1.1.2
From: sip:caller@university.edu;tag=3413415
From: sip:caller@organization.org
To: sip:user@company.com
Content-Type: application/sdp
v=0
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o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.13 INVITE with Illegal Expires Header
This message contains an Expires header which has illegal values for
a number of components, but otherwise is syntactically correct.
Message Details
INVITE sip:user@company.com SIP/2.0
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Max-Forwards: 88
CSeq: 0 INVITE
Call-ID: 98asdh@10.1.1.2
Expires: Thu, 44 Dec 19999 16:00:00 EDT
From: sip:caller@university.edu;tag=3651
To: sip:user@company.com
Content-Type: application/sdp
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.14 200 OK Response with Broadcast Via Header
This message is a response with a 2nd Via header of 255.255.255.255.
On receiving this response, the top Via header is stripped and the
packet forwarded. Since the next address is the broadcast address,
it causes the packet to be broadcast onto the network. A smart server
should ignore packets with 2nd Via headers that are 255.255.255.255
or 127.0.0.1. At the very least it should not crash.
Message Details
Johnston, et al. Informational [Page 198]
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SIP/2.0 200 OK
Via: SIP/2.0/UDP 135.180.130.57;branch=0
Via: SIP/2.0/UDP 255.255.255.255;branch=0
Max-Forwards: 70
Call-ID: 0384840201@10.1.1.1
CSeq: 0 INVITE
From: sip:user@company.com;tag=11141343
To: sip:user@university.edu;tag=2229
Content-Type: application/sdp
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 224.2.17.12/127
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.15 INVITE with Invalid Via and Contact Headers
This is a request with the Via and Contact headers incorrect. They
contain additional semicolons and commas without parameters or
values.
The server should respond with a Bad Request error.
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=134161461246
Max-Forwards: 7
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;;,;
Contact: "" <> ;,"Joe" <sip:joe@org.org>;;,,;;
Content-Type: application/sdp
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
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7.16 INVITE with Incorrect Content-Length Header
This is a request message with a Content Length that is much larger
than the length of the body.
When sent UDP, the server should respond with an error. With TCP,
there's not much you can do but wait...
Message Details
INVITE sip:user@company.com SIP/2.0
Max-Forwards: 80
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=93942939o2
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133
Content-Type: application/sdp
Content-Length: 9999
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.17 INVITE with Invalid Value for Content-Length
This is a request message with a negative value for Content-Length.
The server should respond with an error.
Message Details
INVITE sip:user@company.com SIP/2.0
Max-Forwards: 254
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=3
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: -999
Johnston, et al. Informational [Page 200]
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v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.18 INVITE with Garbage after Message Body
This is a request message with garbage after the end of the SDP
included in the body.
The servers should reject the request as the body is longer than the
Content-Length.
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:j.user@company.com
From: sip:caller@university.edu;tag=3223
Max-Forwards: 7
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133
Content-Type: application/sdp
Content-Length: 138
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
asdpasd08asdsdk:;;asd
a0sdjhg8a0''...'';;;;
7.19 INVITE with Error in Display Name in To Header
This is a request with an unterminated quote in the display name of
the To field.
The server can either return an error, or proxy it if it is
Johnston, et al. Informational [Page 201]
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successful parsing without the terminating quote.
Message Details
INVITE sip:user@company.com SIP/2.0
To: "Mr. J. User <sip:j.user@company.com>
From: sip:caller@university.edu;tag=93334
Max-Forwards: 10
Call-ID: 0ha0isndaksdj@10.0.0.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5050;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 138
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.20 INVITE with a Semicolon-Separated Parameter in the "user" Part
This is an INVITE request with a semicolon-separated parameter in
the "user" part.
Outbound proxies should direct it appropriately.
Message Details
INVITE sip:user;par=u%40h.com@company.com SIP/2.0
To: sip:j_user@company.com
From: sip:caller@university.edu;tag=33242
Max-Forwards: 3
Call-ID: 0ha0isndaksdj@10.1.1.1
CSeq: 8 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
7.21 INVITE with Illegal Enclosing of Request-URI in "<>"
This INVITE is illegal because the Request-URI has been enclosed
within in "<>".
An intelligent server may be able to deal with this and fix up
Johnston, et al. Informational [Page 202]
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athe Request-URI if acting as a Proxy. If not it should respond 400
with an appropriate reason phrase.
Message Details
INVITE <sip:user@company.com> SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=39291
Max-Forwards: 23
Call-ID: 1@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=3149328700 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.22 INVITE with Illegal LWS within Elements of Request-URI
This INVITE has illegal LWS within the SIP URI.
An intelligent server may be able to deal with this and fix up
the Request-URI if acting as a Proxy. If not it should respond 400
with an appropriate reason phrase.
Message Details
INVITE sip:user@company.com; transport=udp SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=231413434
Max-Forwards: 5
Call-ID: 2@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
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t=3149328700 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.23 INVITE with illegal >1 SP between elements of Request URI
This INVITE has illegal >1 SP between elements of the Request-URI.
An intelligent server may be able to deal with this and fix up
the Request-URI if acting as a Proxy. If not it should respond 400
with an appropriate reason phrase.
Message Details
INVITE sip:user@company.com SIP/2.0
Max-Forwards: 8
To: sip:user@company.com
From: sip:caller@university.edu;tag=8814
Call-ID: 3@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.24 INVITE with a legal SIP URI containing escaped characters
This INVITE is legal and has a Request-URI with a SIP URI containing
escaped characters.
Message Details
INVITE sip:sip%3Auser%40example.com@company.com;other-param=summit
SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=938
Max-Forwards: 87
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Call-ID: 4@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.25 INVITE with the illegal use of escaped headers in Request-URI
This INVITE is illegal as it the Request-URI contains a SIP URI
containing
escaped headers.
An intelligent server may be liberal enough to accept this. A server
acting as a proxy should remove the escaped header before processing.
Message Details
INVITE sip:user@company.com?Route=%3Csip:sip.example.com%3E SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=341518
Max-Forwards: 7
Call-ID: 5@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.26 INVITE containing an unknown scheme in the Request URI
Johnston, et al. Informational [Page 205]
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This INVITE contains an unknown URI scheme in the Request-URI.
A server should reject this message with a 400 response plus an
appropriate reason phrase despite being able to understand the
To header as a SIP URI.
Message Details
INVITE name:user SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=384
Max-Forwards: 3
Call-ID: 6@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133;branch=z9hG4bKkdjuw
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.27 OPTIONS with no LWS between display name and <
This OPTIONS request is legal despite there being no LWS between
the display name and < in the From header.
Message Details
OPTIONS sip:user@company.com SIP/2.0
To: sip:user@company.com
From: "caller"<sip:caller@example.com>;tag=323
Max-Forwards: 70
Call-ID: 1234abcd@10.0.0.1
CSeq: 1 OPTIONS
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
7.28 OPTIONS with extran LWS between display name and <
This OPTIONS request is legal despite there being extra LWS between
the display name and < in the From header.
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Message Details
OPTIONS sip:user@company.com SIP/2.0
To: sip:user@company.com
From: "caller" <sip:caller@example.com>;tag=32
Max-Forwards: 70
Call-ID: 1234abcd@10.0.0.1
CSeq: 2 OPTIONS
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
7.29 INVITE with an illegal SIP Date format.
This INVITE is illegal as it contains a non GMT time zone in the SIP
Date header.
An intelligent server may be able to fix this up and correct the time
to GMT. Alternatively this message may illicit a 400 response with an
appropriate reason phrase.
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=2
Max-Forwards: 70
Call-ID: 7@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Date: Fri, 01 Jan 2010 16:00:00 EST
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.30 INVITE with Passed Expries Time
This is a legal INVITE but the message content has long since
expired.
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A server should respond 408 (Timeout).
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=3843
Max-Forwards: 70
Call-ID: 8@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Expires: Thu, 01 Dec 1994 16:00:00 GMT
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.31 INVITE with Max-Forwards Set to Zero
This is a legal SIP request with the Max-Forwards header set to zero.
A proxy or gateway should not forward the request and respond 483
(Too Many Hops).
Message Details
INVITE sip:user@company.com SIP/2.0
To: sip:user@company.com
From: sip:caller@university.edu;tag=3ghsd41
Call-ID: 9@10.0.0.1
CSeq: 1 INVITE
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Max-Forwards: 0
Content-Type: application/sdp
Content-Length: 174
v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
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m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.32 REGISTER with a Escaped Header in a Legal SIP URI of a Contact
This is a legal REGISTER message where the Contact header contains a
SIP URI with an escaped header within it.
Message Details
REGISTER sip:company.com SIP/2.0
To: sip:user@company.com
From: sip:user@company.com;tag=8
Max-Forwards: 70
Contact: sip:user@host.company.com
Call-ID: k345asrl3fdbv@10.0.0.1
CSeq: 1 REGISTER
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Contact: <sip:user@example.com?Route=%3Csip:sip.example.com%3E>
7.33 REGISTER with a Escaped Header in a Illegal SIP URI of a Contact
This is an illegal message as the REGISTER request contains a SIP
URI with an escaped header but it is not enclosed in <>
A server should respond 400 with an appropriate reason phrase.
Message Details
REGISTER sip:company.com SIP/2.0
To: sip:user@company.com
From: sip:user@company.com;tag=998332
Max-Forwards: 70
Contact: sip:user@host.company.com
Call-ID: k345asrl3fdbv@10.0.0.1
CSeq: 1 REGISTER
Via: SIP/2.0/UDP 135.180.130.133:5060;branch=z9hG4bKkdjuw
Contact: sip:user@example.com?Route=%3Csip:sip.example.com%3E
7.34 INVITE with Long Values in Headers
This is a legal message that contains long values in many headers.
Johnston, et al. Informational [Page 209]
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Message Details
INVITE sip:user@company.com SIP/2.0
To: "I have a user name of extreme proportion"
<sip:user@company.com:6000;other-
param=1234567890somethingelselong1234567890>
From: sip:caller@university.edu;tag=12481841982424
Call-ID:
kl24ahsd546folnyt2vbak9sad98u23naodiunzds09a3bqw0sdfbsk34poouymnae004
3nsed09mfkvc74bd0cuwnms05dknw87hjpobd76f
CSeq: 1 INVITE
P-My-State: sldkjflzdsfaret0803adgaasd0afds0asdaasd
Via: SIP/2.0/TCP sip33.example.com
Via: SIP/2.0/TCP sip32.example.com
Via: SIP/2.0/TCP sip31.example.com
Via: SIP/2.0/TCP sip30.example.com
Via: SIP/2.0/TCP sip29.example.com
Via: SIP/2.0/TCP sip28.example.com
Via: SIP/2.0/TCP sip27.example.com
Via: SIP/2.0/TCP sip26.example.com
Via: SIP/2.0/TCP sip25.example.com
Via: SIP/2.0/TCP sip24.example.com
Via: SIP/2.0/TCP sip23.example.com
Via: SIP/2.0/TCP sip22.example.com
Via: SIP/2.0/TCP sip21.example.com
Via: SIP/2.0/TCP sip20.example.com
Via: SIP/2.0/TCP sip19.example.com
Via: SIP/2.0/TCP sip18.example.com
Via: SIP/2.0/TCP sip17.example.com
Via: SIP/2.0/TCP sip16.example.com
Via: SIP/2.0/TCP sip15.example.com
Via: SIP/2.0/TCP sip14.example.com
Via: SIP/2.0/TCP sip13.example.com
Via: SIP/2.0/TCP sip12.example.com
Via: SIP/2.0/TCP sip11.example.com
Via: SIP/2.0/TCP sip10.example.com
Via: SIP/2.0/TCP sip9.example.com
Via: SIP/2.0/TCP sip8.example.com
Via: SIP/2.0/TCP sip7.example.com
Via: SIP/2.0/TCP sip6.example.com
Via: SIP/2.0/TCP sip5.example.com
Via: SIP/2.0/TCP sip4.example.com
Via: SIP/2.0/TCP sip3.example.com
Via: SIP/2.0/TCP sip2.example.com
Via: SIP/2.0/TCP sip1.example.com
Via: SIP/2.0/TCP
host.example.com;received=135.180.130.133;branch=C1C3344E2710000000E2
99E568E7potato10potato0potato0
Content-Type: application/sdp
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v=0
o=mhandley 29739 7272939 IN IP4 126.5.4.3
s=-
c=IN IP4 135.180.130.88
t=0 0
m=audio 492170 RTP/AVP 0 12
m=video 3227 RTP/AVP 31
a=rtpmap:31 LPC
7.35 OPTIONS with multiple headers.
This is an illegal and badly mangled message.
A server should respond 400 with an appropriate reason phrase if it
can. It may just drop this message.
Message Details
OPTIONS sip:135.180.130.133 SIP/2.0
Via: SIP/2.0/UDP company.com:5604
Max-Forwards: 70
From: sip:iuser@company.com;tag=74345345
To: sip:user@135.180.130.133
Call-ID: 1804928587@company.com
CSeq: 1 OPTIONS
Expires: 0 0l@company.com
To: sip:user@135.180.130.133
Call-ID: 1804928587@company.com
CSeq: 1 OPTIONS
Contact: sip:host.company.com
Expires: 0xpires: 0sip:host.company.com
Expires: 0
Contact: sip:host.company.com
7.36 INVITE with large number of SDP attributes and telephone subscriber
Request-URI
This is a legal message with a large number of SDP attributes and a
long telephone subscriber Request-URI
Message Details
INVITE sip:+19725552222;phone-
context=name%40domain;new=user?%22Route%3a%20X%40Y%3bZ=W%22@gw1.atlan
ta.com;user=phone SIP/2.0
Via: SIP/2.0/UDP iftgw.biloxi.com:5060;branch=z9hG4bKjeefr3
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Max-Forwards: 70
From:
<sip:+13035551111@ift.client.atlanta.com;user=phone>;tag=332lflke
To: sip:+16555552222@ss1.atlanta.com;user=phone
Call-ID: 1717@ift.client.atlanta.com
CSeq: 56 INVITE
Content-Type: application/sdp
Content-Length: 320
v=0
o=faxgw1 2890844527 2890844527 IN IP4 iftgw.biloxi.com
s=-
c=IN IP4 iftmg.biloxi.com
t=0 0
m=image 49172 udptl t38
a=T38FaxVersion:0
a=T38maxBitRate:14400
a=T38FaxFillBitRemoval:0
a=T38FaxTranscodingMMR:0
a=T38FaxTranscodingJBIG:0
a=T38FaxRateManagement:transferredTCF
a=T38FaxMaxBuffer:260
a=T38FaxUdpEC:t38UDPR
7.37 REGISTER with a contact parameter.
This REGISTER contains a contact where the 'user' parameter should be
interpreted as being a contact-param and not a url-param.
The register should succeed but a subsequent retrieval of the
registration must not include "user=phone" as a url-parameter.
Message Details
REGISTER sip:bell-tel.com SIP/2.0
Via: SIP/2.0/UDP saturn.bell-tel.com:5060;branch=z9hG4bKkdjuw
Max-Forwards: 70
From: sip:watson@bell-tel.com;tag=DkfVgjkrtMwaerKKpe
To: sip:watson@bell-tel.com
Call-ID: 70710@saturn.bell-tel.com
CSeq: 2 REGISTER
Contact: sip:+19725552222@gw1.atlanta.com;user=phone
7.38 REGISTER with a url parameter.
This register contains a contact where the 'user'parameter is a url-
param.
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The register should succeed and a subsequent retrieval of the
registration must
include "user=phone" as a url-parameter.
Message Details
REGISTER sip:bell-tel.com SIP/2.0
Via: SIP/2.0/UDP saturn.bell-tel.com:5060;branch=z9hG4bKkdjuw
Max-Forwards: 70
From: sip:watson@bell-tel.com;tag=838293
To: sip:watson@bell-tel.com
Call-ID: 70710@saturn.bell-tel.com
CSeq: 3 REGISTER
Contact: <sip:+19725552222@gw1.atlanta.com;user=phone>
7.39 INVITE with an Unquoted Display Name Containing Multiple Tokens
This is a legal INVITE where the To and From header contain display
names that contain multiple tokens but are unquoted.
Message Details
INVITE sip:t.watson@ieee.org SIP/2.0
Via: SIP/2.0/UDP c.bell-tel.com:5060;branch=z9hG4bKkdjuw
Max-Forwards: 70
From: A. Bell <sip:a.g.bell@bell-tel.com>;tag=459843
To: T. Watson <sip:t.watson@ieee.org>
Call-ID: 31414@c.bell-tel.com
CSeq: 1 INVITE
7.40 INVITE with an Unquoted Display Name Containg Non-Token Characters
This is an illegal invite at the display names in the To and From
headers contain non-token characters but are unquoted.
A server may be intelligent enough to cope with this but may also
return a 400 response with an appropriate reason phrase.
Message Details
INVITE sip:t.watson@ieee.org SIP/2.0
Via: SIP/2.0/UDP c.bell-tel.com:5060;branch=z9hG4bKkdjuw
Max-Forwards: 70
From: Bell, Alexander <sip:a.g.bell@bell-tel.com>;tag=43
To: Watson, Thomas <sip:t.watson@ieee.org>
Call-ID: 31415@c.bell-tel.com
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CSeq: 1 INVITE
7.41 INVITE with Unknown (Higher) Protocol Version in Start Line
This is an illegal INVITE as the SIP Protocol version is unknown.
The server should respond to the request with a bad version error.
Message Details
INVITE sip:t.watson@ieee.org SIP/7.0
Via: SIP/2.0/UDP c.bell-tel.com;branch=z9hG4bKkdjuw
Max-Forwards: 70
From: A. Bell <sip:a.g.bell@bell-tel.com>;tag=qweoiqpe
To: T. Watson <sip:t.watson@ieee.org>
Call-ID: 31417@c.bell-tel.com
CSeq: 1 INVITE
7.42 INVITE with RFC2543 syntax
This is a legal message per RFC 2543 which should be accepted by RFC
3261 elements which want to maintain backwards compatibility.
Message Details
INVITE sip:UserB@biloxi.com SIP/2.0
Via: SIP/2.0/UDP iftgw.biloxi.com
From: <sip:+13035551111@ift.client.atlanta.com;user=phone>;tag=93752
Record-Route: <sip:UserB@biloxi.com;maddr=ss1.wcom.com>
To: sip:+16505552222@ss1.atlanta.com;user=phone
Call-ID: 1717@ift.client.atlanta.com
CSeq: 56 INVITE
8 Security Considerations
Since this document represents NON NORMATIVE examples of SIP session
establishment and interworking between SIP and the PSTN, the security
considerations in RFC 3261 [RFC3261] and [SIP-ISUP] apply.
9 IANA Considerations
None.
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10 Acknowledgements
Thanks to Rohan Mahy, Adam Roach, Gonzalo Camarillo, Cullen Jennings,
and Tom Taylor for their detailed comments during the final final
review.
The authors wish to thank Neil Deason for his additions to the
Torture Test messages and Kundan Singh for performing parser
validation of messages.
The authors wish to thank the following individuals for their
participation in the final review of this call flows document: Aseem
Agarwal, Rafi Assadi, Ben Campbell, Sunitha Kumar, Jon Peterson, Marc
Petit-Huguenin, Vidhi Rastogi, and Bodgey Yin Shaohua.
The authors also wish to thank the following individuals for their
assistance: Jean-Francois Mule, Hemant Agrawal, Henry Sinnreich,
David Devanatham, Joe Pizzimenti, Matt Cannon, John Hearty, the whole
MCI WorldCom IPOP Design team, Scott Orton, Greg Osterhout, Pat
Sollee, Doug Weisenberg, Danny Mistry, Steve McKinnon, and Denise
Ingram, Denise Caballero, Tom Redman, Ilya Slain, Pat Sollee, John
Truetken, and others from MCI WorldCom, 3Com, Cisco, Lucent and
Nortel.
11 References
[RFC3261] J. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston,
J. Peterson, R. Sparks, M. Handley, and E. Schooler, "SIP:
Session Initiation Protocol", Internet Engineering Task Force,
Work in Progress.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A. and L. Stewart, "HTTP authentication:
Basic and Digest Access Authentication", RFC 2617, June 1999.
[RFC3264] J.Rosenberg and H.Schulzrinne, "An Offer/Answer Model
with SDP", Internet Engineering Task Force, RFC 3264, April 2002.
[RFC2401] S. Kent, R. Atkinson, "Security Architecture for the
Internet Protocol", RFC 2401, November 1998.
[RFC2246] Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
RFC 2246, January 1999.
[RFC2806] A. Vaha-Sipila, "URLs for Telephone Calls", Internet Draft,
Internet Engineering Task Force, RFC 2806, April 2000.
[SIP-ISUP] G. Camarillo, "Best Current Practice for ISUP to SIP
Mapping", Internet Draft, Internet Engineering Task Force,
Work in progress.
Johnston, et al. Informational [Page 215]
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Author's Addresses
All listed authors actively contributed large amounts of text to this
document.
Alan Johnston
WorldCom
100 South 4th Street
St. Louis, MO 63102
USA
EMail: alan.johnston@wcom.com
Steve Donovan
dynamicsoft, Inc.
5100 Tennyson Parkway
Suite 1200
Plano, Texas 75024
USA
EMail: sdonovan@dynamicsoft.com
Robert Sparks
dynamicsoft, Inc.
5100 Tennyson Parkway
Suite 1200
Plano, Texas 75024
USA
EMail: rsparks@dynamicsoft.com
Chris Cunningham
dynamicsoft, Inc.
5100 Tennyson Parkway
Suite 1200
Plano, Texas 75024
USA
EMail: ccunningham@dynamicsoft.com
Dean Willis
dynamicsoft, Inc.
5100 Tennyson Parkway
Suite 1200
Plano, Texas 75024
USA
Email: dwillis@dynamicsoft.com
Johnston, et al. Informational [Page 216]
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Jonathan Rosenberg
dynamicsoft
72 Eagle Rock Ave
East Hanover, NJ 07936
USA
EMail: jdrosen@dynamicsoft.com
Kevin Summers
Sonus
1701 North Collins Blvd, Suite 3000
Richardson, TX 75080
USA
Email: kevin.summers@sonusnet.com
Henning Schulzrinne
Dept. of Computer Science
Columbia University
1214 Amsterdam Avenue
New York, NY 10027
USA
EMail: schulzrinne@cs.columbia.edu
Copyright Notice
"Copyright (C) The Internet Society 2002. All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
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The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
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