SIPPING D. Petrie
Internet-Draft SIPez LLC.
Intended status: Standards Track S. Channabasappa, Ed.
Expires: September 2, 2007 CableLabs
March 2007
A Framework for Session Initiation Protocol User Agent Profile Delivery
draft-ietf-sipping-config-framework-10
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Abstract
This document defines a framework to enable configuration of Session
Initiation Protocol (SIP) User Agents in SIP deployments. The
framework provides a means to deliver profile data that User Agents
need to be functional, automatically and with minimal (preferably
none) User and Administrative intervention. The framework describes
how SIP User Agents can discover sources, request profiles and
receive notifications related to profile modifications. As part of
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this framework, a new SIP event package is defined for notification
of profile changes. The framework provides for multiple data
retrieval options, without requiring or defining retrieval protocols.
The framework does not include specification of the profile data
within its scope.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.1. Reference Model . . . . . . . . . . . . . . . . . . . . . 6
3.2. Profile Life Cycle . . . . . . . . . . . . . . . . . . . 9
3.3. Data Model and Profile Types . . . . . . . . . . . . . . 10
4. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1. Client with different Data and SIP Service Providers . . 11
4.2. Clients supporting multiple users from different
Service Providers . . . . . . . . . . . . . . . . . . . . 13
5. Profile Delivery Framework . . . . . . . . . . . . . . . . . . 15
5.1. Profile Discovery . . . . . . . . . . . . . . . . . . . . 18
5.1.1. SIP SUBSCRIBE for the Local-Network Profile Type . . . 19
5.1.2. SIP SUBSCRIBE for the Device Profile Type . . . . . . 20
5.1.3. SIP SUBSCRIBE for the User Profile Type . . . . . . . 24
5.1.4. Caching of SIP Subscription URIs . . . . . . . . . . . 24
5.2. Profile Enrollment . . . . . . . . . . . . . . . . . . . 25
5.3. Profile Notification . . . . . . . . . . . . . . . . . . 26
5.4. Profile Retrieval . . . . . . . . . . . . . . . . . . . . 26
5.5. Profile Change Upload . . . . . . . . . . . . . . . . . . 26
5.6. Additional Considerations . . . . . . . . . . . . . . . . 27
5.6.1. Manual retrieval of the Device Profile . . . . . . . . 27
5.6.2. Client Types . . . . . . . . . . . . . . . . . . . . . 28
5.6.3. Profile Data . . . . . . . . . . . . . . . . . . . . . 28
5.6.4. Profile Data Frameworks . . . . . . . . . . . . . . . 28
5.6.5. Additional Profile Types . . . . . . . . . . . . . . . 29
6. Event Package Definition . . . . . . . . . . . . . . . . . . . 29
6.1. Event Package Name . . . . . . . . . . . . . . . . . . . 29
6.2. Event Package Parameters . . . . . . . . . . . . . . . . 29
6.3. SUBSCRIBE Bodies . . . . . . . . . . . . . . . . . . . . 33
6.4. Subscription Duration . . . . . . . . . . . . . . . . . . 33
6.5. NOTIFY Bodies . . . . . . . . . . . . . . . . . . . . . . 34
6.6. Notifier Processing of SUBSCRIBE Requests . . . . . . . . 34
6.7. Notifier Generation of NOTIFY Requests . . . . . . . . . 35
6.8. Subscriber Processing of NOTIFY Requests . . . . . . . . 35
6.9. Handling of Forked Requests . . . . . . . . . . . . . . . 36
6.10. Rate of Notifications . . . . . . . . . . . . . . . . . . 36
6.11. State Agents . . . . . . . . . . . . . . . . . . . . . . 36
7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
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7.1. Example 1: Client requesting profile . . . . . . . . . . 36
7.2. Example 2: Client obtaining change notification . . . . . 40
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 44
8.1. SIP Event Package . . . . . . . . . . . . . . . . . . . . 44
8.2. New HTTP Event Header . . . . . . . . . . . . . . . . . . 44
9. Security Considerations . . . . . . . . . . . . . . . . . . . 45
9.1. Event Package . . . . . . . . . . . . . . . . . . . . . . 45
9.2. Profile Life Cycle . . . . . . . . . . . . . . . . . . . 46
9.3. Profile Data . . . . . . . . . . . . . . . . . . . . . . 46
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 47
11. Open Items . . . . . . . . . . . . . . . . . . . . . . . . . . 47
12. Change History . . . . . . . . . . . . . . . . . . . . . . . . 48
12.1. Changes from
draft-ietf-sipping-config-framework-09.txt . . . . . . . 48
12.2. Changes from
draft-ietf-sipping-config-framework-08.txt . . . . . . . 49
12.3. Changes from
draft-ietf-sipping-config-framework-07.txt . . . . . . . 49
12.4. Changes from
draft-ietf-sipping-config-framework-06.txt . . . . . . . 49
12.5. Changes from
draft-ietf-sipping-config-framework-05.txt . . . . . . . 50
12.6. Changes from
draft-ietf-sipping-config-framework-04.txt . . . . . . . 50
12.7. Changes from
draft-ietf-sipping-config-framework-03.txt . . . . . . . 51
12.8. Changes from
draft-ietf-sipping-config-framework-02.txt . . . . . . . 51
12.9. Changes from
draft-ietf-sipping-config-framework-01.txt . . . . . . . 51
12.10. Changes from
draft-ietf-sipping-config-framework-00.txt . . . . . . . 51
12.11. Changes from
draft-petrie-sipping-config-framework-00.txt . . . . . . 52
12.12. Changes from draft-petrie-sip-config-framework-01.txt . . 52
12.13. Changes from draft-petrie-sip-config-framework-00.txt . . 52
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 53
13.1. Normative References . . . . . . . . . . . . . . . . . . 53
13.2. Informative References . . . . . . . . . . . . . . . . . 54
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 54
Intellectual Property and Copyright Statements . . . . . . . . . . 56
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1. Introduction
SIP User Agents require configuration data to function properly.
Examples include network, Client and user specific information.
Ideally, this configuration process should be automatic and require
minimal or no user intervention.
Many deployments of SIP User Agents require dynamic configuration and
cannot rely on pre-configuration. This framework provides a standard
means of providing dynamic configuration which simplifies deployments
containing SIP User Agents from multiple vendors.
This framework also addresses modifications to profiles and the
corresponding change notifications to the SIP User Agents using a new
event package. However, the framework does not define the content or
format of the actual profile data, leaving that to future
standardization activities.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
In addition, this document introduces and utilizes the following
terms:
Client: software or hardware entity containing one or more SIP user
agents.
Device: the terms 'Client' and 'Device' are used interchangeably
within this framework.
Service Provider: a logical entity providing one or more services.
This can refer to private enterprises or public entities.
Profile: configuration data set specific to an entity (for example,
user, device, local network or other).
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Profile Type: a particular category of Profile data (for example,
User, Device, Local Network or other).
Profile Delivery Server (PDS): the source of a Profile, it is the
logical collection of the Profile Notification Component (PNC) and
the Profile Content Component(PCC).
Profile Notification Component (PNC): the logical component of a
Profile Delivery Server that is responsible for enrolling Clients
and providing profile notifications.
Profile Content Component (PCC): the logical component of a Profile
Delivery Server that is responsible for storing, providing and
accepting profile content.
Profile Discovery: discovery of a Profile Delivery Server (PDS) by
the Client.
Profile Enrollment: process of enrolling with one or more Profile
Delivery Server(s) by a Client.
Profile Notification: notification of a requested or changed profile
by the PDS.
Profile Retrieval: retrieval of Profile data from a PDS by a Client.
Profile Change Upload: upload of profile data changes to one or more
PDSs by authorized entities such as a Client
Notifier: as defined in [RFC3265] the SIP user agent server which
processes SUBSCRIBE requests for events and sends NOTIFY requests
with profile data or URIs (Uniform Resource Identifiers) that
point to the data.
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Instance ID: text identifier globally unique across all Clients.
3. Overview
This section provides an overview of the configuration framework. It
introduces the reference model and explains key concepts such as the
Profile Life Cycle and the Profile types. The framework is presented
in Section 5.
3.1. Reference Model
The design of the framework was the result of a careful analysis to
identify the configuration needs of a wide range of SIP deployments.
As such, the reference model provides for a great deal of
flexibility, while breaking down the interactions to their basic
forms which can be reused in many different scenarios.
In its simplest form, the reference model for the framework defines
the interactions between the Profile Delivery Server(PDS) and the
Client. The Client is a SIP UA which needs the profile data to
effectively function in the network. The PDS is responsible for
responding to Client requests and providing the profile data. The
set of interactions between these entities is referred to as the
Profile Life Cycle. This reference model is illustrated in the
diagram below.
+-------------------------+
+---------+ Interactions | Profile Delivery Server |
| Client |<==========================>| +---+ +---+ |
| (SIP UA)| (Profile Life Cycle) | |PNC| |PCC| |
+---------+ | +---+ +---+ |
+-------------------------+
PNC = Profile Notification Component
PCC = Profile Content Component
Framework Reference Model
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The PDS is subdivided into two logical components:
o Profile Notification Component (PNC), responsible for enrolling
Clients in Profile event subscriptions and providing Profile
change notifications;
o Profile Content Component (PCC), responsible for storing,
providing access to, and accepting updates related to profile
content.
SIP deployments vary considerably. To be effective, the
configuration framework needs to consider a comprehensive set of
scenarios that is representative of most deployments. The figure
below provides a system level view of the device, user and Service
Provider relationships that may be involved.
--------
/ \
| Service |
| Provider | - > Provides 'Client'(e.g. allowed Users)
\ Y / & 'User'(such as Services) profile
--------
| -----
| / Local \
| | Network |
| | Provider| - > Provides 'Local Network' profile
| \ Z / data (e.g. STUN Server Address)
| -----
| /
| /
===============
( Local Network )
===============
|
|
|
---------
| Client X| - > Needs the 'Client' profile (from Y)
--------- & 'local network' profile (from Z)
/ \
/ \
------ ------
|User A| |User B| - > Users need 'User' profile (from Y)
------ ------
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Framework System Level Model
Based on the system level model, the following considerations are
relevant.
Client connectivity:
o Clients can connect either directly to a Service Provider or via
other local networks (for example, home network, Public Wi-Fi
Hotspots, enterprise managed LAN, etc.);
o Local networks through which Clients connect may wish to provide
their own configuration information particular to that specific
network (for example, STUN server information, local Proxy, etc.)
which is independent of the Service Provider (who provides
services) or the particular User.
Service provider relationships:
o The local network provider (the network the Client connects to)
and the Service Provider (that hosts the actual voice or other
services) can often be different entities, with no administrative
or business relationship to each other;
o There may be multiple different Service Providers involved, one
for each service type a User subscribes to (telephony service,
instant messaging, etc); this Framework does not specify explicit
behavior in such a scenario, but it does not prohibit its usage
either
o Each User accessing services via a Client may subscribe to
different sets of services, from different Service Providers;
User-Client relationship:
o The relationship between Clients and Users can be many-to-many
(for example, a particular UA instance may allow for many Users to
obtain subscription services through it, and individual Users may
have access to multiple different UA devices);
o Each User may have different preferences for use of services, and
presentation of those services in the Client user interface;
o Each User may have different personal information applicable to
use of the Client device, either as related to particular
services, or independent of them.
The observations above show a need for a clear distinction between
different Profile Types, based on the source and purpose of the
configuration data contained, and a need for these profiles to be
manageable by different PDSs. Accordingly, the framework identifies
the following minimal Profile Types.
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Local-Network Profile: refers to profile data as provided by the
Local Network to which a Client is directly connected;
Device Profile: refers to profile data provided by the Service
Provider or other entity which is specific to the particular
Client;
User Profile: refers to profile data provided by the Service
Provider or other entity which is specific to the particular User.
The definition of additional Profile Types and their usage is
allowed, but is outside the scope of this document.
The remainder of this section provides more information on the two
vital components of the framework: Profile Life Cycle and Profile
Types.
3.2. Profile Life Cycle
Automated Profile delivery to Clients requires proactive behavior on
the part of a Client. It also requires one or more PDSs which
provide the profile data. Profile Delivery is usually initiated when
the Client discovers PDSs and requests profile data. The profile
data can be modified by the Client (for example, by a User) and
subsequently uploaded to the PDS. Alternatively, the profile data
can be modified by an authorized entity such as an administrative or
user interface and the Client is notified through an event
notification.
The specific functional steps involved in these interactions,
collectively termed Profile Life Cycle, are as follows:
Profile Discovery: The process by which a Client finds PDS(s)
capable of providing the Profiles it requires. This Framework
defines multiple Profile Types which may be served by one or more
PDSs.
Profile Enrollment: The process by which a Client makes itself known
to a PDS. While enrolling, the Client provides identity
information and requested Profile Type(s) for profile retrieval.
It also subscribes for notification of profile changes. As a
result of enrollment, the Client receives profile information
(contents or content indirection information). Each Profile Type
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requires a separate enrollment or SUBSCRIBE session.
Profile Notification: The process by which the PDS notifies the
Client that either requested Profile contents are available, or
the content of one or more of the Profiles has changed. If the
content is provided indirectly, the Client may retrieve the
profile from the specified URI upon receipt of the change
notification.
Profile Retrieval: The process of retrieving the content for each of
the Profiles requested by the Client.
Profile Change Upload: The process by which a Client or other entity
(for example, configuration management server) pushes a change to
Profile data to the PDS.
3.3. Data Model and Profile Types
As outlined previously, this framework defines three specific Profile
Types. Additional extended profiles may also be defined. The
Profile Types specified in this framework are:
Local Network Profile: Contains configuration data related to the
Local Network to which a Client is directly connected, as required
for the Client to operate effectively in that network. It is
expected to be provided by a PDS in the Local Network (or proxied
in some way).
Device Profile: Contains configuration data related to a specific
Client, required for operation in the Service Provider's
environment. It is expected to be provided by the Service
Provider responsible for configuring the Client.
User Profile: Contains configuration data related to the specific
User, as required to reflect that User's preferences and the
particular services subscribed to. It is expected to be provided
by Service Provider(s) responsible for maintaining the User's
configuration data.
To function effectively, the Client should obtain all of the
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necessary Profiles. Since each profile may potentially be served by
a different source and the Client has no way of ascertaining that in
advance, the framework requires the Client to discover the PDS
sources independently and request the corresponding Profiles from
each individually.
4. Use Cases
This section provides a small - non-comprehensive - set of
representative use cases to further illustrate how this Framework can
be utilized in SIP deployments.
For Security Considerations please refer to Section 9.
4.1. Client with different Data and SIP Service Providers
Description: Consider a user who obtains data (broadband) and SIP
Services from two different Service Providers. For example, a user
obtaining SIP services from a SIP Service Provider, via data
connectivity provided through a WiFi hotspot or hotel network.
The following assumptions apply:
o For the sake of simplicity, the Client is assumed to be pre-
configured with a) the domain name of the SIP Service Provider,
b) the ability to generate a Client identifier (such as, based
on MAC address) that can be used to request the device profile,
and b) a user identity which can be used to request the user
profile
o The Client is pre-configured to request local-network, Client
and user profiles - in that order - to obtain information
related to the local-network, itself and the pre-configured user
o The profile data provided upon request are based on data models
that are comprehenisble by the Client, i.e. the Client
understands the data models used for the creation of the profile
data
The following diagram illustrates this use case and highlights the
communications relevant to the framework specified in this document.
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+-----------------+ +----------------------+
+--------+ | Data Service | | SIP Service Provider |
| Client | | Provider | | |
|(SIP UA)| | | | SIP PDS PDS |
+--------+ | DHCP PDS | | PROXY (Client) (User)|
+-----------------+ +----------------------+
| | | | | |
(A) |<==== DHCP ===>| | | | |
| | | | |
| | | | |
| SUBSCRIBE/NOTIFY | | | |
(B) |<=== local-network ===>| | | |
| profile
|
| <<Profile Retrieval>>
|
| SUBSCRIBE/NOTIFY | | |
(C) |<========= device profile ========>|<=====>| |
| | | |
| <<Profile Retrieval>>
|
|
| SUBSCRIBE/NOTIFY | |
(D) |<========== user profile ========>|<============>|
| | |
| <<Profile Retrieval>>
|
The following is an explanation of the interactions in the diagram.
(A) Upon initialization, the Client obtains IP parameters (IP
address, DNS) using DHCP (as an example)
(B) The Client proceeds to request the 'local-network' Profile Type.
The PDS in the local network responds, allowing the Client to
retrieve the local-network profile
(C) The Client then proceeds to request the 'device' Profile Type
using the pre-configured SIP Service Provider's domain name.
This request is received by a SIP Proxy in the SIP Service
Provider's network. The request is then proxied to a relevant
PDS within its network. The PDS responds to the request and
provides profile retrieval information. The Client retrieves
the Device Profile (this can contain information such as
enabling or disabling usage, based on the subscription status)
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(D) The Client then proceeds to request the 'User' Profile Type for
the pre-configured User. This message is proxied to the same or
different PDS (diagram assumes the latter) which responds with
the profile retrieval information. The Client retrieves the
User profile (this can contain information such as service
profiles to be retrieved, based on the subscription). The
Client then starts providing services.
4.2. Clients supporting multiple users from different Service Providers
Description: Consider a single Client (for example, Kiosk at an
airport) that allows for multiple users to obtain services from a
list of pre-configured SIP Service Providers.
The following assumptions apply:
o The Client is provided and managed by SIP Service Provider A. It
is not pre-configured with any User Identities, but offers an
interactive User Interface to enter Service Provider and User
information
o SIP Service Provider A provides the local network connectivity,
'local-network' and 'device' profiles for the Client. The
Service Provider also provides 'user' profiles for existing
subscribers
o SIP Service Provider B provides SIP services and has pre-
existing agreements with SIP Service Provider A. This Service
Provider also provides 'user' profiles for existing subscribers
The following diagram illustrates the use case and highlights the
communications relevant to the framework specified in this document.
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User User
A B +----------------------+ +----------------------+
+--------+ | SIP Service Provider | | SIP Service Provider |
| Client | | A | | B |
|(SIP UA)| | | | |
+--------+ | DHCP PROXY PDS | | PROXY PDS |
+----------------------+ +----------------------+
| | | | | |
(A) |<====DHCP====>| | | | |
| | | | |
| | | | |
| SUBSCRIBE/NOTIFY | | | |
(B) |<local-network profile>|<====>| | |
|
| <<Profile Retrieval>>
|
|
| SUBSCRIBE/NOTIFY | | | |
(C) |<== device profile ==> |<====>| | |
|
| <<Profile Retrieval>>
|
.
.
.
[[User A attempts services]]
| SUBSCRIBE/NOTIFY | | | |
(D) |<= user profile (A) => |<====>| | |
| | | | |
|
| <<Profile Retrieval>>
.
.
.
.
[[User B attempts services]]
|
| SUBSCRIBE/NOTIFY | |
(E) |<=========== user profile (B) ==========>|<=========>|
| | |
| <<Profile Retrieval>>
|
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The following is an explanation of the interactions in the diagram.
(A) Upon initialization, the Client obtains IP parameters (IP
address, DNS) using DHCP
(B) Once local IP connectivity is established and the SIP stack
initialized, the Client proceeds to request the 'local-network'
Profile Type. It receives a response from the PDS in Service
Provider A's network (the local network). The Client retrieves
the profile (this may contain useful information such as
firewall port restrictions, available bandwidth etc)
(C) The Client then proceeds to request the 'device' Profile Type.
It receives a response containing the profile retrieval from the
PDS in Service Provider A's network. The Client retrieves the
data provided in the Client Profile (this may provide data
regarding Users such as the list of SIP Service Providers the
Client can communicate with). The Client initializes the User
interface for services.
(D) User A with a pre-existing subscription with Service Provider A
attempts communication via the User Interface. This results in
a prompt - and responses - for identification and
authentication. The Client uses the provided information and
communicates with Service Provider A. Once authenticated and
authorized, it proceeds to request the 'User' Profile Type. The
PDS responds with the profile retrieval information. The Client
provides services to User A.
(E) At a different point in time, User B with a pre-existing
subscription with Service Provider B attempts communication via
the User Interface. This results in a prompt - and responses -
for identification and authentication. Since Service Provider B
is in the list of approved Service Provider, the Client uses the
provided information and communicates with Service Provider B.
Once authenticated and authorized, it proceeds to request the
'User' Profile Type. The PDS responds with the profile
retrieval information. The Client provides services to User B.
It is to be noted that this Client may allow for exclusive or
simultaneous access to both Users.
5. Profile Delivery Framework
This section details the framework requirements. The Profile Life
Cycle (introduced in Section 3), is examined in further detail, with
requirements that apply to the Client and the PDS. Unless explicitly
enhanced or indicated by an implementing specification, the Client
and the PDS MUST follow the Profile Life Cycle requirements stated in
this section for all supported Profile Types.
A high-level representation of the framework is shown in the
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following state diagram. Each of the specified Profile Types is
retrieved individually, in the specified order (see below), until all
needed Profiles have been received. For each retrieved Profile, the
Client then awaits any Change Notifications
---------------
/ Client \
\ Initialization/
---------------
|
| Completes IP initialization;
| Initializes SIP stack
|
V
-------------- YES ---------------
________\ / All profiles?\_____\ | Await Change |
| / \ retrieved? / / | Notifications |
| -------------- ---------------
| |
| | NO; attempt
| | Profile Request
| | in specified order
| |
| V
| ------------
___________/ Profile \
\ Life Cycle /
------------
Framework state diagram
The Profile Life Cycle, within each Profile Type, is illustrated
further as in the state diagram below.
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------------- All methods --------
________\ / Profile \ ............\ / Error \
| / \ Discovery / exhausted / \Handling/
| ------------- --------
| |
| |
| Try | Send request
| alternate | for Profile
| method(s) | Enrollment
| |
| |
| V
| FAILURE ------------
|__________/ Profile \
^ \ Enrollment /
^ ------------
| |
| FAILURE |
| |
| |
| V
| Timeout -------------
_________ / Profile \
\ Notification/
-------------
|
|
|SUCCESS
|
V
------- Failure ---------
/ Profile \ _________\ / Error \
\Retrieval/ / \ Handling/
------- ---------
.
. If allowed
. by Profile Retrieval
------ . Framework
(Client) -- V
------ \ -------------
/Profile Change\
\ Upload /
---------- / -------------
{Authorized}--
{ Entity }
----------
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The Profile Life Cycle is initiated when the Client starts the
'Profile Discovery' process for a particular Profile Type. Discovery
leads to transmission of a request for 'Profile Enrollment'.
Successful enrollment leads to 'Profile Notification'. Successful
initial notification results in 'Profile Retrieval' (either as data
within the notification or using content indirection). 'Profile
Change Upload' can be initiated by any authorized entity (examples
include Clients and administrative interfaces).
'Profile Discovery' and 'Profile Enrollment' are closely coupled.
Failure to enroll (for example, no response is received for the
SUBSCRIBE) results in alternate 'Profile Discovery' methods until
success is achieved or all the methods are exhausted (resulting in
error handling). Simiarly, the initial 'Profile Notification' is
closely coupled to enrollment. Failure to receive the initial
notification also results in alternate discovery methods.
'Profile Retrieval' is accomplished using the contents of the Profile
Notification. This can either contain the profile data or a content
indirection method to achieve it.
The Profile Life Cycle is the same for all the Profile Types, but
there are different requirements in each step based on the Profile
Types. This framework defines three Profile Types and an order that
MUST be followed by the Client in requesting them (when it retrieves
two or more of the defined Profile Types), as follows:
o local-network
o device
o user
The sub-sections that follow specify the Profile Life Cycle details,
with specific requirements based on each Profile Type.
5.1. Profile Discovery
The first step to obtaining a profile is PDS Discovery. This is
accomplished by creating a profile subscription using the Event
Package described in Section 6, and preparing for Profile Enrollment.
Each Profile Type requires its own subscription and based on the
entity requesting it, presents certain unique requirements (for
example, the Client identifier is provided for the Device Profile
Type where as the User identifier is provided for the User Profile
Type). Further, the Profile Types are aimed at different PDSs and
hence are identified differently (for example, the local-network is
identified by the local domain name where as the Service Provider is
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identified based on the Service Provider's domain name). Some of
this information can be obtained in multiple ways (such as local
domain information that can be configured statically or dynamically)
and the Client may have to try different information sources to
obtain the required information (for example, dynamic configuration
can override statically configured information). Based on these
considerations, the framework defines different rules for obtaining
and presenting the information for each Profile Type. Additionally,
when more than one information source is possible for the
information, it is presented as well. This is highlighted in the
following sub-sections.
5.1.1. SIP SUBSCRIBE for the Local-Network Profile Type
Before attempting to create a SIP SUBSCRIBE requesting the Local-
Network Profile, the Client MUST have established local network
connectivity. It MUST also have knowledge of the local network
domain either via static configuration or dynamic discovery (using
DHCP [RFC2131], option 15 [RFC2132]). The following requirements
apply:
o the user part of the Request URI MUST NOT be provided. The host
and port part of the Request URI MUST be set to the local network
domain
o the user part of the "From" field MUST be the Identifier that the
Client will use to request the 'device' Profile Type
o the host and port part of the "From" field MUST be set to the
local network domain
o a user AOR, if known to the Client MUST be provided in the
"network-user" event header parameter, unless privacy requirements
prohibit its use (this is useful if the user has privileges in the
local network beyond those of the default user)
For example: If the Client requested and received the local domain
name via DHCP to be: airport.example.net, then the Local-Network
Profile SUBSCRIBE Request URI would look like:
sip:airport.example.net
The Event header would look like the following if the Client decided
to provide sip:alice@example.com as the user's AOR. (Alice may have
a prior arrangement with the local network operator giving her
special privileges.):
Event: ua-profile;profile-type=local-network;
network-user="sip:alice@example.com"
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The Local-Network Profile SUBSCRIBE Request URI does not have a user
part so that the URI is distinct between the "local" and "device"
URIs when the domain is the same for the two. This provides a means
of routing to the appropriate PDS in domains where they are distinct
servers. The From field uses the device ID in the user part of the
local network Request URI so that every device in the network has a
unique and constant From field. Even though every client may get the
same (or similar) Local-Network Profile, the uniqueness of the From
field provides an important capability. Having unique From fields
allows the management of the local network to track user agents
present in the network and consequently also manage resources such as
bandwidth and port allocation.
For example: If the Client requested and received the local domain
name via DHCP to be: airport.example.net and the device ID is: MAC:
00DF1E004CD0, the From field would contain:
sip:MAC%3a00DF1E004CD0@airport.example.net
5.1.2. SIP SUBSCRIBE for the Device Profile Type
The Device Profile Type allows the Service Provider managing a Client
to provide Client-specific configuration information. To enable
this, the Request URI needs to identify the Client and the PDS domain
within which it is recognizable. Accordingly, this Framework
presents the following requirements for the formation of a
Subscription Request URI to request the "device" Profile Type
o the user portion of the Request URI MUST be set to a unique Client
Identifier
o the host and port portion of the Request URI MUST be set to the
PDS domain
The following sub-sections explain identification of - and the
requirements related to - the Client Identifier and the PDS domain
discovery.
5.1.2.1. Client Identifier
The Client profile could be specific to each Client in a SIP
deployment (for example, vendor/model) or shared across Client types
(for example, based on services and service tiers). Further, the
same Client might be provided different configuration profiles based
on deployment models. Client Identifiers play a significant role in
ensuring delivery of the correct profile and hence need to be unique
within a PDS domain to support the various deployment models.
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This Framework requires that Client Identifiers MUST be unique and
persistent over the lifetime of a Client. Client Identifier
representations auto-generated by Clients SHOULD be based on MAC
address or UUID ([RFC4122]) based representations. A Client may use
alternate Client identifiers (for example, SIP URIs) obtained via
pre-configuration or dynamic configuration (for example, Client
profile).
If a MAC address is used, the following requirements apply:
o the Client identifier MUST be formatted as the characters "MAC:"
followed by a twelve digit hexadecimal upper case representation
of the MAC address to form a proper URN ([RFC2141]). The MAC
address representation MUST NOT include visual separators such as
colons and whitespaces. The representation is denoted using the
following ABNF syntax
mac-ident = MAC ":" 12UHEX
MAC = %x4d.41.43 ; MAC in caps
UHEX = DIGIT / %x41-46 ; uppercase A-F
o the MAC address MUST only be used to represent a single Client.
It MUST NOT be used if more than one Client can potentially use
the same MAC Address (for example, multiple software Clients on a
single platform). In such cases, the UUID representation SHOULD
be used
If a UUID is used, the following requirements MUST apply:
o the same approach to defining a user agent Instance ID as
[RFC4122] MUST be used
o when the URN is used as the user part of the URI, it MUST be URL
escaped
The colon (":") is not a legal character (without being
escaped) in the user part of an addr-spec ([RFC4122]).
For example the instance ID:
urn:uuid:f81d4fae-7ced-11d0-a765-00a0c91e6bf6@example.com
would be escaped to look as follows in a URI:
sip:urn%3auuid%3af81d4fae-7ced-11d0-a765-00a0c91e6bf6@
example.com
The ABNF for the UUID representation is provided in [RFC4122]
5.1.2.2. PDS Domain Discovery
A Client needs to identify the PDS domain to form the host and port
part of the Request URI. Ideally, this information should be
obtained via a single method. However, support for various
deployment models implies multiple Client environments (for example,
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residential routers, enterprise LANs, WLAN hotspots, dialup modem
etc) and presents hurdles to specifying a single method (for example,
if a Client is always in the SIP Service Provider's network one could
use DHCP). To accommodate multiple deployment scenarios, the
framework specified in this document presents multiple approaches.
Clients MUST follow the procedures specified below in the order
presented, unless exceptions are made by Client manufacturers or
Service Providers who may provide an option for the user to choose
the order (to suit specific deployment models, for example).
1. Service Provider pre-configuration
The Client MAY be pre-configured with information that can be
utilized to identify the host and port of the Request URI. The
information can be provided - as examples - when the Client is
manufactured, by using Service Provider entities (flash card, SIM
card) or via a Service Provider specific method (for example,
information or methods that lead to self subscription). If the
Client is specified to utilize this approach, it MUST attempt to
do so before trying other methods. The details of how this is
accomplished are beyond the scope of this document.
2. IP Configuration
If pre-configuration is not an option, or not available, IP
configuration MUST be utilized to try and obtain information that
can help with identification of the host and port for the Request
URI. The framework defines the following methods within this
procedure to accomplish this. Clients MUST follow the methods
defined, in the order specified, i.e. if the first option cannot
be accomplished or results in a failure, then next method is
tried. Failure of a specific method is indicated when the Client
cannot successfully complete Profile Enrollment.
2a. DHCP option 120:
Clients that support DHCP MUST attempt to obtain the host and
port of the outbound proxy during the DHCP process, using the
SIP DHCP option 120 [RFC3361] and use these as the host and
port part of the request URI.
For example, a MAC based Client Identifier with a DHCP option
120 indicating example.com, the Request URI would be
constructed as sip:MAC%3aABC123EFD456@example.com
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2b. Local IP Network Domain:
- Clients that support DHCP MUST attempt to obtain the local IP
network domain during the DHCP process, using DHCP option 15
and use these as the host and port part of the request URI
using the technique specificed in [RFC3263]
+ For example, a MAC based Client Identifier with a DHCP
option 15 indicating local.example.com, the Request URI
would be constructed as
sip:MAC%3aABC123EFD456@local.example.com
- If the local IP network domain is available (previous
method), but the usage of the local IP Network domain results
in a failure, the Client MUST use the local IP network domain,
prefixing it using the label "sipuaconfig."
+ For example, a MAC based Client Identifier with a DHCP
option 15 indicating local.example.com, the Request URI
would be constructed as
sip:MAC%3aABC123EFD456@sipuaconfig.local.example.com
3. Manual
If pre-configuration and IP Configuration are not options or
result in failures, the Client SHOULD provide a means for the user
to present information that may help with the retrieval process.
Exceptions to this requirement MAY include Clients with no user
interface appropriate for such entry.
This framework provides the following alternatives which can be
considered individually or together, in any order.
Service Provider PDS information: The user SHOULD be allowed to
present the host and port information which can help with the
creation of the Subscription URI to locate a PDS capable of
providing the profile.
Service Provider Configuration Server information The user MAY be
allowed to present information pertaining to a configuration
server that provides the Device Profile, not using a PDS as
defined in this framework. This framework specifies one such
possible process in Section 5.6.1.
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5.1.3. SIP SUBSCRIBE for the User Profile Type
The User Profile allows the responsible SIP Service Provider to
provide user-specific configuration. This is based on the User's
Identity that is usually known in the network (for example,
associated with a subscription). Similar to the profiles provided to
Clients, the content and propagation of User Profiles may partake
differently, based on deployment scenarios (for example, users
belonging to the same subscription might - or might not - be provided
the same profile). However, each User is uniquely identified in a
SIP Service Provider's network using an Address Of Record (AOR).
Clients implementing this framework MUST use the User's AOR to
populate the Request URI.
A Client MAY obtain the User's AOR using various methods such as pre-
configuration, via the Device Profile or dynamically via a User
Interface.
5.1.4. Caching of SIP Subscription URIs
Creation of Subscription URIs is vital for successful Profile
Enrollment, required for Profile Notification and ultimately Profile
Retrieval. Further - unlike the User Profile - Local-Network and
Device Profiles are expected to be requested based on discovered
information (for example, domain name discovered via DHCP). These
Profile Types have different goals and hence, caching of the
Subscription URI should be carefully considered.
The Local-Network Profile Type is aimed at obtaining information from
the local network. The local network can change across Client
initializations (for example, User moves the Client from a home
network to a workplace LAN). Thus, the Client SHOULD NOT remember
local-network profile subscription URIs across initializations. The
Client SHOULD re-create the Subscription URI every time it moves to a
new network or gets re-initialized. Exceptions may be cases where
the Client can unambiguously determine changes to the local network.
The Device Profile Type is aimed at obtaining information from the
SIP Service Provider managing the Client. Once established, the
Service Provider does not change often (an example of an exception
would be the re-use of Clients across Service Providers). However,
if the discovery process is used, the Client can only be sure of
having reached the Service Provider upon successful Profile
Enrollment and Profile Notification. Thus, the Client SHOULD cache
the Subscription URI for the Device Profile. When cached, the Client
should use the cached Subscription URI upon a reset. Exceptions
include cases where the Client identifier has changed (for example,
new network card with a new MAC address), Service Provider
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information has changed (for example, user initiates change) or the
Client cannot obtain its profile using the Subscription URI.
Clients SHOULD NOT cache the Subscription URI for the Device
Profile Type until successful Profile Notification. The reason
for this is that a PDS may send 202 responses to SUBSCRIBE
requests and NOTIFY responses to unknown Clients (see Section 6.6)
with no profile data or URIs. Thus, successful Profile
Notification is the only sure way to know that the Subscription
URI is valid.
5.2. Profile Enrollment
Clients implementing the framework specified in this document are
required to perform Profile Enrollment prior to Profile Retrieval
(the only exception is noted in Section 5.6.1). Enrollment for a
specific profile happens once the specific Subscription URI is formed
and is accomplished using the Event Package specified.
Thus, a Client requesting a Profile Type specified in this document -
and is successful in forming a Subscription URI - MUST enroll using
the event package defined, and as specified, in this framework (see
Section 6) . The following requirements apply:
o the Client MUST cater to the Event Package requirements specified
in Section 6.2 (for example, indicate the Profile Type being
requested in the profile-type parameter)
o the Client MUST use the Subscription URI pertaining to the Profile
Type being requested, as specified in Section 5.1
The SIP infrastructure receiving such requests is expected to relay
and process profile enrollment requests. When a Profile Enrollment
request is received by a PDS, it SHOULD accept and respond to any
profile requests. Exceptions are when Service Provider policy
prevents such a response (for example, requesting entity is unknown).
Successful Profile Enrollment involves the following
o Acceptance of the SUBSCRIBE request by a PDS (indicated via a 200
response)
o Receipt of an initial Profile Notification within the timeouts as
specified in [RFC3265]
A Client SHOULD follow suitable BackOff and Retry mechanisms if a
successful Profile Enrollment does not happen within the expected
period.
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5.3. Profile Notification
Successful Profile Enrollment leads to Profile Notification. This
serves two purposes a) initial profile content following successful
Profile Enrollment and b) notification to the Client of modifications
to profile content. Failure to receive the initial NOTIFY following
a successful enrollment MUST be treated the same as a failed
enrollment. Whenever a profile is changed, the PDS MUST NOTIFY all
Clients currently subscribed to the changed profile.
For NOTIFY content please refer to Section 6.5.
5.4. Profile Retrieval
Upon successful Profile Enrollment and Profile Notification, the
Client can retrieve the documents pertaining to the requested profile
directly or via the URI(s) provided in the NOTIFY request as
specified in Section 6.5.
The following requirements hold good:
o the PDS SHOULD secure the content of the profiles using one of the
techniques described in Section 9
o the Client MUST make the new profiles effective within the
specified timeframe, as described in Section 6.2
o if content indirection is used, the Client SHOULD verify that it
has the latest profile content using the "hash" parameter defined
in [RFC4483]
o the Client SHOULD cache (i.e. store persistently) the contents of
retrieved profiles, until overridden by subsequent Profile
Notifications (this avoids situations where a PDS is unavailable,
leaving the Client without required configuration)
5.5. Profile Change Upload
Configuration Profiles can change over time. This can be initiated
by various entities (for example, via the Client, back-office
components, end-user web interfaces into configuration servers, etc)
and for various reasons (such as, change in user preferences,
modifications to services, enterprise-imposed common features or
restrictions). This framework allows for such changes to be
communicated to the PDS, using the term Profile Change Upload.
Any changes to a Profile as a result of Profile Change Upload MUST
result in a Profile Notification to all enrolled clients for that
Profile, if any.
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Definition of specific mechanisms for Profile Change Upload are out
of scope of this document.
5.6. Additional Considerations
This section provides a special case for retrieval of the Device
Profile and highlights considerations and requirements on external
entities such as Profile Data Frameworks.
5.6.1. Manual retrieval of the Device Profile
At a minimum, a Client requires the Device Profile to be able to
function effectively. However, the methods specified in this
document many fail to provide a Client with a profile. To illustrate
with an example, consider the case of a Client that finds itself
behind a local network which does not provide information about DNS
servers in the network (for example, misconfigured home network). In
such cases, it would be beneficial to employ an alternative means to
obtain the profile information (for example, resolvable DNS Servers
could be part of the Client profile). While this specification
recommends that such a method be made available, it also specifies
one such option using HTTP that is described in this sub-section.
Clients expected to encounter scenarios where Client profile
retrieval can be hindered may employ the specified - or any
alternative - process.
The method being described involves the Client to utilize a HTTPS URI
(and any required credentials) based on either pre-configuration or
manual entry by the User (in cases where such an interface is
possible). This can lead to the retrieval of the Device Profile
which may contain the properties for the SUBSCRIBE Request URI and
credentials for Profile Enrollment and Profile Notification. This
approach bootstraps the process in a different step in the cycle, but
uses the same framework.
Further, this document defines a new HTTP request header "Event".
The syntax of the HTTP Event header is the same as the SIP Event
header defined in this document. Similar to the SIP Event header the
purpose of the HTTP Event header is to define the content of the
state information to be retrieved. In particular, the state
information is the Device, User or Local-Network Profile for the
Client. The SIP Event header parameters for this event package
("profile-type", "vendor", "model", "version") are also mandatory for
the HTTP Event header as they are used to provide information as to
what profile type is requested along with information about the
device which may impact the contents of the profile.When the Client
starts with retrieval of the profile via HTTPS (instead of a SIP
SUBSCRIBE to the event package), the device MUST provide the Event
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header defined.
5.6.2. Client Types
The examples in this framework tend to associate Clients with
entities that are accessible to end-users. However, this is not
necessarily the only type of Client that can utilize the specified
Framework. Clients can be entities such as User Interfaces (that
allow for Client Configuration), entities in the network that do not
directly communicate with any Users (for example, Service Provider
deployed gateways) or elements in the Service Provider's network (for
example, SIP servers).
5.6.3. Profile Data
This framework does not specify the contents for any Profile Type.
Follow-on standardization activities can address profile contents.
However, it makes the following assumptions and recommendations:
o When the Client receives multiple profiles, the contents of each
Profile Type will only contain data relevant to the entity it
represents. As an example, consider a Client that obtains all the
defined profiles. Information pertaining to the local network is
contained in the 'local-network' profile and not the'user'
profile. This does not preclude relevant data about a different
entity from being included in a Profile Type, for example, the
'device' Profile Type may contain information about the Users
allowed to access services via the Client. A profile may also
contain starting information to obtain subsequent Profiles
o Data overlap SHOULD be avoided across Profile Types, unless
necessary. If data overlap is present, prioritization of the data
is left to data definitions. As an example, the Device Profile
may contain the list of codecs to be used by the Client and the
User Profile (for a User on the Client) may contain the codecs
preferred by the User. Thus, the same data (usable codecs) is
present in two profiles. However, the data definitions may
indicate that to function effectively, any codec chosen for
communication needs to be present in both the profiles.
5.6.4. Profile Data Frameworks
This framework specified in this document does not address profile
data representation, storage or retrieval protocols. It assumes that
the PDS has a PCC based on existing or other Profile Data Frameworks,
for example, XCAP ([I-D.ietf-simple-xcap]).
While it does not impose vast constraints on any such framework, it
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does allow for the propagation of profile content to PDS
(specifically the PCC). Thus, Profile Data or Retrieval frameworks
used in conjunction with this framework MAY consider techniques for
propagating incremental, atomic changes to the PDS. For example, a
means for propagating changes to a PDS is defined in XCAP
([I-D.ietf-simple-xcap]).
5.6.5. Additional Profile Types
This document specifies three profile types: local-network, device
and user. However, there may be use cases for additional profile
types. For example, Profile Types for application specific profile
data. Definition of such additional Profile Types is not prohibited,
but considered out of scope for this document.
6. Event Package Definition
The framework specified in this document proposes and specifies a new
SIP Event Package as allowed by [RFC3265]. The purpose is to allow
for Clients to subscribe to specific Profile Types with PDSs and for
the PDSs to notify the Clients with - or pointers to - profile data.
The requirements specified in [RFC3265] apply to this package. The
following sub-sections specify the Event Package description and the
associated requirements. The framework requirements are defined in
Section 5.
6.1. Event Package Name
The name of this package is "ua-profile". This value appears in the
Event header field present in SUBSCRIBE and NOTIFY requests for this
package as defined in [RFC3265].
6.2. Event Package Parameters
This package defines the following new parameters for the event
header:
"profile-type", "vendor", "model", "version", "effective-by" and
"network-user".
The following rules apply:
o All the new parameters, with the exception of the "effective-by"
parameter MUST only be used in SUBSCRIBE requests and ignored if
they appear in NOTIFY requests
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o The "effective-by" parameter is for use in NOTIFY requests only
and MUST be ignored if it appears in SUBSCRIBE requests
The semantics of these new parameters are specified in the following
sub-sections.
6.2.1. profile-type
The "profile-type" parameter is used to indicate the token name of
the Profile Type the user agent wishes to obtain data or URIs for and
to be notified of subsequent changes. This document defines three
logical types of profiles and their token names. They are as
follows:
local-network Specifying "local-network" type profile indicates the
desire for profile data (URI when content indirection is used)
specific to the local network.
device Specifying "device" type profile(s) indicates the desire for
the profile data (URI when content indirection is used) and change
notification of the contents of the profile that is specific to
the device or user agent.
user Specifying "user" type profile indicates the desire for the
profile data (URI when content indirection is used) and change
notification of the profile content for the user.
The "profile-type" is identified is identified in the Event header
parameter: profile-type. A separate SUBSCRIBE dialog is used for
each Profile Type. The Profile Type associated with the dialog can
then be used to infer which Profile Type changed and is contained in
the NOTIFY or content indirection URI. The Accept header of the
SUBSCRIBE request MUST include the MIME types for all profile content
types for which the subscribing user agent wishes to retrieve
profiles or receive change notifications.
In the following syntax definition using ABNF, EQUAL and token are
defined in [RFC3261]. It is to be noted that additional Profile
Types may be defined in subsequent documents.
Profile-type = "profile-type" EQUAL profile-value
profile-value = profile-types / token
profile-types = "device" / "user" / "local-network"
The "device", "user" or "local-network" token in the profile-type
parameter may represent a class or set of profile properties.
Follow-on standards defining specific profile contents may find it
desirable to define additional tokens for the profile-type parameter.
Also additional content types may be defined along with the profile
formats that can be used in the Accept header of the SUBSCRIBE to
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filter or indicate what data sets of the profile are desired.
6.2.2. vendor, model and version
The "vendor", "model" and "version" parameter values are tokens
specified by the implementer of the user agent. These parameters
MUST be provided in the SUBSCRIBE request for all Profile Types. The
implementer SHOULD use their DNS domain name (for example,
example.com) as the value of the "vendor" parameter so that it is
known to be unique. These parameters are useful to the PDS to affect
the profiles provided. In some scenarios it is desirable to provide
different profiles based upon these parameters. For example, feature
property X in a profile may work differently on two versions of the
same user agent. This gives the PDS the ability to compensate for or
take advantage of the differences. In the following ABNF defining
the syntax, EQUAL and quoted-string are defined in [RFC3261].
Vendor = "vendor" EQUAL quoted-string
Model = "model" EQUAL quoted-string
Version = "version" EQUAL quoted-string
6.2.3. network-user
The "network-user" parameter MUST be set when subscribing for "local-
network" profiles if it is known, unless the Client is provisioned to
preserve privacy within the local network. This allows the Client to
indicate a user who may have special privileges in the local network
that impact the contents of the "local-network" profile. It MAY also
be provided in a subscription for a "device" profile. In such cases
the Client is requesting the PDS to recognize the indicated user as
the default user for itself.
The Notifier SHOULD authenticate the subscriber to verify the
resource identifier in the "network-user" parameter, if the profile
provided is specific to the user (for example, granting policies or
privileges beyond those of a default user). If the value of the
"profile-type" parameter is not "device" or "local-network", the
"network-user" parameter has no defined meaning and is ignored. If
the "network-user" parameter is provided in the SUBSCRIBE request, it
MUST be present in the NOTIFY request as well. In the following
ABNF, EQUAL, LDQUOT, RDQUOT and addr-spec are defined in [RFC3261].
Network-User = "network-user" EQUAL LDQUOT addr-spec RDQUOT
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6.2.4. effective-by parameter
The "effective-by" parameter in the Event header of the NOTIFY
request specifies the maximum number of seconds before the user agent
must attempt to make the new profile effective. The "effective-by"
parameter MAY be provided in the NOTIFY request for any of the
Profile Types. A value of 0 (zero) indicates that the subscribing
user agent must attempt to make the profiles effective immediately
(despite possible service interruptions). This gives the PDS the
power to control when the profile is effective. This may be
important to resolve an emergency problem or disable a user agent
immediately. The "effective-by" parameter is ignored in all messages
other than the NOTIFY request. In the following ABNF, EQUAL and
DIGIT are defined in [RFC3261].
Effective-By = "effective-by" EQUAL 1*DIGIT
6.2.5. Summary of event parameters
The following are example Event headers which may occur in SUBSCRIBE
requests. These examples are not intended to be complete SUBSCRIBE
requests.
Event: ua-profile;profile-type=device;
vendor="vendor.example.com";model="Z100";version="1.2.3"
Event: ua-profile;profile-type="user";
vendor="premier.example.com";model="trs8000";version="5.5"
The following are example Event headers which may occur in NOTIFY
requests. These example headers are not intended to be complete
SUBSCRIBE requests.
Event: ua-profile;effective-by=0
Event: ua-profile;effective-by=3600
The following table shows the use of Event header parameters in
SUBSCRIBE requests for the three Profile Types:
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profile-type || device | user | local-network
=============================================
vendor || m | m | m
model || m | m | m
version || m | m | m
network-user || s | | s
effective-by || | |
m - mandatory
s - SHOULD be provided
o - optional
Non-specified means that the parameter has no meaning and should be
ignored.
The following table shows the use of Event header parameters in
NOTIFY requests for the three Profile Types:
profile-type || device | user | local-network
=============================================
vendor || | |
model || | |
version || | |
network-user || s | | s
effective-by || o | o | o
6.3. SUBSCRIBE Bodies
This package defines no use of the SUBSCRIBE request body. If
present, it MUST be ignored.
Future enhancements to the framework may specify a use for the
SUBSCRIBE request body (for example,, mechanisms using etags to
minimize Profile Notifications to Clients with current profile
versions).
6.4. Subscription Duration
The duration of a subscription is specific to SIP deployments and no
specific recommendation is made by this Event Package. If absent, a
value of 86400 seconds is RECOMMENDED since the presence (or absence)
of a Client subscription is not time critical to the regular
functioning of the PDS.
It is to be noted that a one-time fetch of a profile can be
accomplished by setting the 'Expires' parameter to a value of Zero,
as specified in [RFC3265].
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6.5. NOTIFY Bodies
The framework specifying the Event Package allows for the NOTIFY body
to contain the profile data or a pointer to the profile data using
content direction. The framework does not define any profile data
and delegates specification of utilized MIME types Profile Data
Frameworks. For profile data delivered via content indirection, the
following apply:
o the Content-ID MIME header, as described in [RFC4483] MUST be used
for each Profile document URI
o at a minimum, the "http:" and "https:" URI schemes MUST be
supported; other URI schemas MAY be supported based on the Profile
Data Frameworks (examples include FTP [RFC0959], TFTP
[RFC3617],HTTP [RFC2616], HTTPS [RFC2818], LDAP [RFC3377], XCAP
[I-D.ietf-simple-xcap], XCAP-DIFF [I-D.ietf-simple-xcap-diff])
The NOTIFY body SHOULD include a MIME type specified in the 'Accept'
header of the SUBSCRIBE. Further, if the Accept header of the
SUBSCRIBE included the MIME type message/external-body (indicating
support for content indirection) the content indirection SHOULD be
used in the NOTIFY body for providing the profiles. If none are
specified, the Profile Data frameworks are responsible for, and MUST
specify, the MIME type to be assumed.
6.6. Notifier Processing of SUBSCRIBE Requests
A successful SUBSCRIBE request results in a NOTIFY with either
profile contents or a pointer to it (via Content Indirection). If
the NOTIFY is expected to contain profile contents or the Notifier is
unsure, the SUBSCRIBE SHOULD be either authenticated or transmitted
over an integrity protected SIP communication channels. Exceptions
to authenticating such SUBSCRIBEs include cases where the identity of
the Subscriber is unknown and the Notifier is configured to accept
such requests.
The Notifier MAY also authenticate SUBSCRIBE messages even if the
NOTIFY is expected to only contain a pointer to profile data.
Securing data sent via Content Indirection is covered in Section 9.
If the Profile Type indicated in the "profile-type" Event header
parameter is unavailable or the Notifier is configured not to provide
it, the Notifier SHOULD return a 404 response to the SUBSCRIBE
request. If the specific user or Client is unknown, the Notifier MAY
either accept or reject the subscription.
When the Event header "profile-type" is "device" and the user agent
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has provided the user's AOR in the "network-user" parameter, the
profile delivery server MAY set or change the default user associated
with the Client indicated in the Subscription request. However, the
Notifier SHOULD authenticate the user indicated before making such a
change.
6.7. Notifier Generation of NOTIFY Requests
As specified in [RFC3265], the Notifier MUST always send a NOTIFY
request upon accepting a subscription. If the Client or User is
unknown and the Notifier choose to accept the subscription, the
Notifier MAY either respond with profile data (for example, default
profile data) or provide no profile information (i.e. no body or
content indirection).
If the URI in the SUBSCRIBE request is a known identity and the
requested profile information is available (i.e. as specified in the
profile-type parameter of the Event header), the Notifier SHOULD send
a NOTIFY with profile data. Profile data MAY be sent as profile
contents or via Content Indirection (if the content indirection MIME
type was included in the Accept header). To allow for Content
Indirection, the Subscriber MUST support the "http:" or "https:" URI
schemas. If the Subscriber wishes to support alternative URI schemas
it MUST be indicated in the "schemes" Contact header field parameter
as defined in [RFC4483]. If the subscriber does not specify the URI
scheme, the Notifier may use either "http:" or "https:".
The Notifier MAY specify when the new profiles must be made effective
by the Subscriber by specifying a maximum time in seconds (zero or
more) in the "effective-by" event header parameter.
If the SUBSCRIBE was received over an integrity protected SIP
communications channel, the Notifier SHOULD send the NOTIFY over the
same channel.
6.8. Subscriber Processing of NOTIFY Requests
A Subscriber to this event package MUST adhere to the NOTIFY request
processing behavior specified in [RFC3265]. If the Notifier
indicated an effective time (using the "effective-by" Event Header
parameter), it SHOULD attempt to make the profiles effective within
the specified time. Exceptions include deployments that prohibit
such behavior in certain cases (for example, emergency sessions are
in progress). When profile data cannot be applied within the
recommended timeframe and this affects Client behavior, any actions
to be taken SHOULD be defined by the profile data definitions. By
default, the Subscriber is RECOMMENDED to make the profiles effective
as soon as possible.
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The Subscriber MUST always support "http:" or "https:" and be
prepared to accept NOTIFY messages with those URI schemas.The
subscriber MUST also be prepared to receive a NOTIFY request with no
body. The subscriber MUST NOT reject the NOTIFY request with no
body. The subscription dialog MUST NOT be terminated by a NOTIFY
with no body.
6.9. Handling of Forked Requests
This Event package allows the creation of only one dialog as a result
of an initial SUBSCRIBE request as described in section 4.4.9 of
[RFC3265]. It does not support the creation of multiple
subscriptions using forked SUBSCRIBE requests.
6.10. Rate of Notifications
The rate of notifications for the profiles in this framework is
deployment specific, but expected to be infrequent. Hence, the Event
Package specification does not specify a throttling or minimum period
between NOTIFY requests
6.11. State Agents
State agents are not applicable to this Event Package.
7. Examples
This section provides examples along with sample SIP message bodies
relevant to this framework. Both the examples are derived from a
snapshot of Section 4.1, specifically the request for the Device
Profile. The examples are purely informative and in case of
conflicts with the framework or protocols used for illustration, the
latter should be deemed normative.
7.1. Example 1: Client requesting profile
This example illustrates the detailed message flows between the
Client and the SIP Service Provider's network for requesting and
retrieving the profile (the flow uses the Device Profile as an
example).
The following are assumed for this example:
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o Client is assumed to have established local network connectivity;
NAT and Firewall considerations are assumed to have been addressed
by the SIP Service Provider
o examples are a snapshot only and do not illustrate all the
interactions between the Client and the Service Provider's network
(and none between the entities in the SIP Service Provider's
network)
o All SIP communication with the SIP Service Provider happens via a
SIP Proxy
o HTTP is assumed to be the Profile Data method used (any suitable
alternative can be used as well)
o TLS is assumed to be the protocol for securing the Profile
Retrieval (any other suitable protocol can be employed);
authentication and security requirements are not addressed
The flow diagram and an explanation of the messages follow.
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+----------------------+
+--------+ | SIP Service Provider |
| Client | | |
|(SIP UA)| | SIP PDS HTTP |
+--------+ | PROXY Server |
| |
+----------------------+
| | | |
| | | |
| SUBSCRIBE | | |
(SReq)|--------device profile--------->| | |
| |------>| |
| |200 OK | |
| 200 OK |<------| |
(SRes)|<-------------------------------| | |
| | | |
| | NOTIFY| |
| NOTIFY (Content Indirection)|<------| |
(NTFY)|<-------------------------------| | |
| 200 OK | | |
(NRes)|------------------------------->|200 OK | |
| |------>| |
| |
| |
| |
|<<<<<<<<<<<<< TLS establishment >>>>>>>>>>>>>|
| |
| HTTP Request |
(XReq)|---------------------------------------------->|
| |
| HTTP Response |
(XRes)|<----------------------------------------------|
| |
(SReq)
the Client transmits a request for the 'device' profile using the
SIP SUBSCRIBE utilizing the Event Package specified in this
framework.
* Note: Some of the header fields (for example, Event, via) are
continued on a separate line due to format constraints of
this document
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SUBSCRIBE sip:MAC%3a000000000000@sip.example.net SIP/2.0
Event: ua-profile;profile-type=device;vendor="vendor.example.net";
model="Z100";version="1.2.3";network-user="sip:user@sip.example.net"
From: sip:MAC%3A000000000000@sip.example.net;tag=1234
To: sip:MAC%3A000000000000@sip.example.net
Call-ID: 3573853342923422@10.1.1.44
CSeq: 2131 SUBSCRIBE
Contact: sip:MAC%3A000000000000@sip.example.net
Via: SIP/2.0/TCP 10.1.1.41;
branch=z9hG4bK6d6d35b6e2a203104d97211a3d18f57a
Accept: message/external-body, application/x-z100-device-profile
Content-Length: 0
(SRes)
the SUBSCRIBE request is received by a SIP Proxy in the Service
Provider's network which transmits it to the PDS. The PDS accepts
the response and responds with a 200 OK
* Note: The Client and the SIP proxy may have established a
secure communications channel (for example, TLS)
(NTFY)
subsequently, the PDS transmits a SIP NOTIFY message indicating
the profile location
* Note: Some of the fields (for example, content-type) are
continued on a separate line due to format constraints of this
document
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NOTIFY sip:MAC%3A000000000000@10.1.1.44 SIP/2.0
Event: ua-profile;effective-by=3600
From: sip:MAC%3A000000000000@sip.example.net;tag=abca
To: sip:MAC%3A000000000000@sip.example.net;tag=1231
Call-ID: 3573853342923422@10.1.1.44
CSeq: 322 NOTIFY
Via: SIP/2.0/UDP 192.168.0.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d0
MIME-Version: 1.0
Content-Type: message/external-body; access-type="URL";
expiration="Mon, 01 Jan 2010 09:00:00 UTC";
URL="http://sip.example.net/z100-000000000000.html";
size=9999
hash=10AB568E91245681AC1B
Content-Type: application/x-z100-device-profile
Content-ID: <39EHF78SA@sip.example.net>
.
.
.
(NRes)
Client accepts the NOTIFY message and responds with a 200 OK
(XReq)
once the necessary secure communications channel is established,
the Client sends an HTTP request to the HTTP server indicated in
the NOTIFY
(XRes)
the HTTP server responds to the request via a HTTP response
containing the profile contents
7.2. Example 2: Client obtaining change notification
The following example illustrates the case where a User (X) is
simultaneously accessing services via two different Clients (for
example, Multimedia Soft Clients on a PC and PDA) and has access to a
User Interface (UI) that allows for changes to the User profile.
The following are assumed for this example:
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o The Clients (A & B) obtain the necessary profiles from the same
SIP Service Provider
o The SIP Service Provider also provides a User Interface (UI) that
allows the User to change preferences that impact the User profile
The flow diagram and an explanation of the messages follow.
o Note: The example only shows retrieval of User X's profile, but it
may request and retrieve other profiles (for example, local-
network, Client).
----- -----
|User |_________| UI* | * = User Interface
| X | | |
----- -----
/ \
/ \
/ \ +----------------------+
+--------+ +--------+ | SIP Service Provider |
| Client | | Client | | |
| A | | B | | SIP PDS HTTP |
+--------+ +--------+ | PROXY Server |
+----------------------+
| | | |
| | | |
(A-EX)|<=Enrolls for User X's profile=>|<=====>| |
| | | |
| |
(A-RX)|<===Retrieves User X's profile================>|
| |
| | | | |
| | Enrolls for | | |
| (B-EX)|<== User X's ==>|<=====>| |
| | profile | | |
| | | | |
| | |
| (B-RX)|<= Retrieves User X's profile=>|
| |
| | |
| (HPut)|---------------------->|
| | |
| (HRes)|<----------------------|
| |
| | | |
| | NOTIFY| |
| NOTIFY |<------| |
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(A-NT)|<-------------------------------| | |
| 200 OK | | |
(A-RS)|------------------------------->|200 OK | |
| |------>| |
| |
| | | NOTIFY| |
| | NOTIFY |<------| |
| (B-NT)|<---------------| | |
| | 200 OK | | |
| (B-RS)|--------------->|200 OK | |
| | |------>| |
| |
| |
(A-RX)|<===Retrieves User X's profile================>|
| |
| | |
| | |
| (B-RX)|<= Retrieves User X's profile=>|
| | |
(A-EX) Client A discovers, enrolls and obtains notification related
to User X's profile
(A-RX) Client A retrieves User X's profile
(B-EX) Client B discovers, enrolls and obtains notification related
to User X's profile
(B-RX) Client B retrieves User X's profile
(HPut) Changes affected by the User via the User Interface (UI) are
uploaded to the HTTP Server
* Note: The UI itself can act as a Client and subscribe to User
X's profile. This is not the case in the example shown.
(HRes) Changes are accepted by the HTTP server
(A-NT) PDS transmits a NOTIFY message to Client A indicating the
changed profile. A sample message is shown below:
Note: Some of the fields (for example, Via) are continued on a
separate line due to format constraints of this document
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NOTIFY sip:userX@10.1.1.44 SIP/2.0
Event: ua-profile;effective-by=3600
From: sip:userX@sip.example.net;tag=abcd
To: sip:userX@sip.example.net.net;tag=1234
Call-ID: 3573853342923422@10.1.1.44
CSeq: 322 NOTIFY
Via: SIP/2.0/UDP 192.168.0.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d1
MIME-Version: 1.0
Content-Type: message/external-body; access-type="URL";
expiration="Mon, 01 Jan 2010 09:00:00 UTC";
URL="http://www.example.com/user-x-profile.html";
size=9999
hash=123456789AAABBBCCCDD
.
.
.
(A-RS) Client A accepts the NOTIFY and sends a 200 OK
(B-NT) PDS transmits a NOTIFY message to Client B indicating the
changed profile. A sample message is shown below:
Note: Some of the fields (for example, Via) are continued on a
separate line due to format constraints of this document
NOTIFY sip:userX@10.1.1.43 SIP/2.0
Event: ua-profile;effective-by=3600
From: sip:userX@sip.example.net;tag=abce
To: sip:userX@sip.example.net.net;tag=1235
Call-ID: 3573853342923422@10.1.1.43
CSeq: 322 NOTIFY
Via: SIP/2.0/UDP 192.168.0.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d2
MIME-Version: 1.0
Content-Type: message/external-body; access-type="URL";
expiration="Mon, 01 Jan 2010 09:00:00 UTC";
URL="http://www.example.com/user-x-profile.html";
size=9999
hash=123456789AAABBBCCCDD
.
.
.
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(B-RS) Client B accepts the NOTIFY and sends a 200 OK
(A-RX) Client A retrieves the updated profile pertaining to User X
(B-RX) Client B retrieves the updated profile pertaining to User X
8. IANA Considerations
There are two IANA considerations associated with this document, SIP
Event Package and HTTP header. These are outlined in this section.
8.1. SIP Event Package
This specification registers a new event package as defined in
[RFC3265]. The following information required for this registration:
Package Name: ua-profile
Package or Template-Package: This is a package
Published Document: RFC XXXX (Note to RFC Editor: Please fill in
XXXX with the RFC number of this specification).
Persons to Contact: Daniel Petrie dan.ietf AT SIPez DOT com,
sumanth@cablelabs.com
New event header parameters: profile-type, vendor, model, version,
effective-by, network-user (the profile-type parameter has
predefined values. The new event header parameters do not)
The following table illustrates the additions to the IANA SIP Header
Field Parameters and Parameter Values: (Note to RFC Editor: Please
fill in XXXX with the RFC number of this specification)
Predefined
Header Field Parameter Name Values Reference
---------------------------- --------------- --------- ---------
Event profile-type Yes [RFCXXXX]
Event vendor No [RFCXXXX]
Event model No [RFCXXXX]
Event version No [RFCXXXX]
Event effective-by No [RFCXXXX]
Event network-user No [RFCXXXX]
8.2. New HTTP Event Header
This document defines a new permanent HTTP request header field:
Event.
Header field name: Event
Applicable protocol: http
Status: standard
Author/Change controller: IETF
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Specification document(s): [RFCXXXX] (Note to RFC Editor: Please
fill in XXXX with the RFC number of this specification).
9. Security Considerations
The framework specified in this document allows Service Providers to
propagate profile data to Clients. This is accomplished by requiring
deployed Clients to implement the framework. The framework
(explained in Section 5) specifies a Profile Life Cycle that allows
Clients to request and obtain profile data. The Profile Life Cycle
is enabled using an Event Package (defined in Section 6) as per
[RFC3265]. Thus, the primary components requiring security
considerations are: Event Package, Profile Life Cycle and Profile
Data. The considerations, requirements and recommendations are
presented in the following sub-sections.
9.1. Event Package
The Event Package usage MUST adhere to the security considerations
and requirements (access control, Notifier privacy mechanism, Denial-
of-Service attacks, replay attacks, and Man-in-the Middle attacks)
specified in Section 5 of [RFC3265]. Specifically for the Event
Package defined in this framework, this sub-section hightlights
additional considerations and security requirements.
The Notifier MUST authenticate any SUBSCRIBE request with a known
identity. It MUST NOT accept any SUBSCRIBE requests that fail an
authentication challenge. Refer to [I-D.ietf-sip-identity] and
[RFC3261] for RECOMMENDED SIP authentication methods.
Unless configured otherwise, the Notifier SHOULD NOT respond to
SUBSCRIBEs without an identity that can be authenticated. Exceptions
include deployments catering to unknown Clients (for example, for
self-subscription) or for troubleshooting (for example, credentials
misplaced by a user). Refer to Section 9.3 for Profile Data
considerations in such cases.
The Notifier MUST transmit NOTIFY messages with sensitive profile
data over an authenticated, integrity protected channel. Refer to
Section 9.3 for information on profile data classification. It
SHOULD transmit Content Indirection information (without profile
data) over an integrity-protected channel, unless configured
otherwise (for example, if the Service Provider is catering to
unknown Clients). For data provided via content indirection,
Subscribers MUST implement the hash verification scheme described in
[RFC4483].
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Subscribers with the ability to authenticate a PDS (for example,
Service Provider Certificates, mutual shared secrets) MUST employ
such mechanisms prior to retrieving data. This framework RECOMMENDS
that Service Providers consider providing this ability to deployed
Clients.
9.2. Profile Life Cycle
Profile Discovery involves various protocols such as DHCP and DNS
that may provide unauthenticated information. Thus, successful
Profile Enrollment and subsequent Profile Notification with an
authenticated PDS (for example, via mutual authentication) are
required to prevent threats such as impersonation or Denial of
Service. Given the nature of these mechanisms and to prevent service
disruption due to such threats, the specification recommends caching
of retrieved profiles (see Section 5.4) by the Clients. It also
provides for multiple Profile Discovery mechanisms (based on Profile
Types) which can minimally aid in thwarting security threats from
individual mechanisms (for example, impersonated DNS).
The specification strongly RECOMMENDS that solutions implementing the
Framework provide the Clients with the ability to recognize, mutually
authenticate and establish integrity protected SIP communication
channels (for example, mutual TLS using certificates). Clients
without such an ability SHOULD report changes to sensitive profile
data (refer to Profile Data) using suitable mechanisms (for example,
management reporting). Further, Clients with access to credentials
(even if obtained via a User Interface) MUST respond to
authentication challenges.
Profile Enrollment and Profile Notification are done via the Event
Package definition and the security requirements have been presented
in Section 9.1. Profile Retrieval and Profile Change Upload are
accomplished using Profile Data Frameworks and are addressed in
Section 9.3.
9.3. Profile Data
Profile data provided using any of the Profile Types is expected to
happen via suitable Profile Data Framework (such as XCAP) or suitable
protocol (such as HTTP). Data defined using such frameworks may be
sensitive (for example, user credentials) or non-sensitive (for
example, list of DNS servers).
If a profile contains sensitive data, it MUST be provided over a
mutual-authenticated, integrity protected channel. Even if the data
is non-sensitive, it SHOULD still be provided over a secure channel.
Exceptions include cases where deployments cater to unknown Clients
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or for troubleshooting.
For profile data delivered within the framework (i.e. data is
provided in the NOTIFY), the requirements specified in Section 9.1.
When the profile data is delivered via content indirection,
authentication, integrity, confidentiality MUST be provided by the
Profile Data Frameworks containing the retrieval mechanisms.
Further, a non-replayable authentication mechanism (for example,
Digest authentication) MUST be used.
10. Acknowledgements
Many thanks to those who contributed and commented on the many
iterations of this document. Detailed comments were provided by the
following individuals: Jonathan Rosenberg from Cisco, Henning
Schulzrinne from Columbia University, Cullen Jennings from Cisco,
Rohan Mahy from Plantronics, Rich Schaaf from Pingtel, Volker Hilt
from Bell Labs, Adam Roach of Estacado Systems, Hisham Khartabil from
Telio, Henry Sinnreich from MCI, Martin Dolly from AT&T Labs, John
Elwell from Siemens, Elliot Eichen and Robert Liao from Verizon, Dale
Worley from Pingtel, Francois Audet from Nortel, Roni Even from
Polycom, Jason Fischl from Counterpath, Josh Littlefield from Cisco,
Nhut Nguyen from Samsung.
The editor would like to extend a special thanks to the experts who
contributed to the restructuring and revisions as proposed by the
SIPPING WG, specifically Keith Drage from Lucent (restructuring
proposal), Peter Blatherwick from Mitel (who also contributed to the
Overview and Introduction sections), Josh Littlefield from Cisco
(examples and diagram suggestions), Alvin Jiang of Engin, Martin
Dolly from AT&T, and Jason Fischl from Counterpath. Additionally,
sincere appreciation is extended to the chairs (Mary Barnes from
Nortel and Gonzalo Camarillo from Ericsson) and the Area Directors
(Cullen Jennings from Cisco and Jon Peterson and Cisco) for
facilitating discussions, and for reviews and contributions.
11. Open Items
[[Editor's note: This is being used a place holder only and will be
removed once the items listed are addressed]]
The following comments are considered to be open (i.e. not addressed)
in this version of the I-D
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o Replace 'Service Provider' with a term better representative of
its definition
o Analyze potential unformity in the formation of the Subscription
URI across Profile Types. If not, provide a bried explanation of
the analysis
o Analyze the current SHOULD v/s MUST requirements for the Profile
Framework to obtain consensus and facilitate interoperability
o Present an analysis of the Local Network Profile discovery methods
in DNS-less environments
o Check on potentially referencing RFC4122 instead of OUTBOUND
o Security Considerations requires further review
12. Change History
[[RFC Editor: Please remove this entire section upon publication as
an RFC.]]
12.1. Changes from draft-ietf-sipping-config-framework-09.txt
Following the ad-hoc SIPPING WG discussions at IETF#67 and as per the
email from Gonzalo Camarillo dated 12/07/2006, Sumanth was appointed
as the new editor. This sub-section highlights the changes made by
the editor (as per expert recommendations from the SIPPING WG folks
interested in this effort) and the author.
Changes incorporated by the editor:
o Document was restructured based on a) Keith's recommendations in
the email dated 11/09/2006 and responses (Peter, Sumanth, Josh) b)
subsequent discussions by the ad-hoc group consisting of the
editor, the author, expert contributors (Peter Blatherwick, Josh
Littlefield, Alvin Jiang, Jason Fischl, Martin Dolly, Cullen
Jennings) and the co-chairs . Further changes follow.
o Use cases were made high-level with detailed examples added later
on
o Several sections were modified as part of the restructuring (for
example, Overview, Introduction, Framework Requirements, Security
Sections)
o General editorial updates were made
Changes incorporated by the author:
o Incorporated numerous edits and corrections from CableLabs review.
o Used better ascii art picture of overview from Josh Littlefield
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o Fixed the normative text for network-user so that it is now
consistant: MAY provide for device profile, MUST provide for
local-network profile.
12.2. Changes from draft-ietf-sipping-config-framework-08.txt
The Request URI for profile-type=localnet now SHOULD not have a
user part to make routing easier. The From field SHOULD now
contain the device id so that device tracking can still be done.
Described the concept of profile-type as a filter and added
normative text requiring 404 for profile types not provided.
Moved "application" profile type to
draft-ietf-sipping-xcap-config-01. The "application" value for
the profile-type parameter will also be used as a requirement that
XCAP be supported.
Fixed text on certificate validation.
Added new HTTP header: Event to IANA section and clean up the IANA
section.
Added diagram for Service Provider use case schenario.
Added clarification for HTTP Event header.
Added clarification of subscriber handling of NOTIFY with no body.
12.3. Changes from draft-ietf-sipping-config-framework-07.txt
Made XCAP informative reference. Removed "document" and "auid"
event header parameters, and Usage of XCAP section to be put in
separate supplementary draft.
Fixed ABNF for network-user to be addr-spec only (not name-addr)
and to be quoted as well.
Synchronized with XCAP path terminology. Removed XCAP path
definition as it is already defined in XCAP.
User agent instance ID is now defined in output (not GRUU).
Clarified the rational for the network-user parameter.
Added text to suggest URIs for To and From fields.
Clarified use of network-user parameter.
Allow the use of the auid and document parameters per request by
the OMA.
12.4. Changes from draft-ietf-sipping-config-framework-06.txt
Restructured the introduction and overview section to be more
consistent with other Internet-Drafts.
Added additional clarification for the Digest Authentication and
Certificate based authentication cases in the security section.
Added two use case scenarios with cross referencing to better
illustrate how the framework works. Added better cross
referencing in the overview section to help readers find where
concepts and functionality is defined in the document.
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Clarified the section on the use of XCAP. Changed the Event
parameter "App-Id" to "auid". Made "auid" mutually exclusive to
"document". "auid" is now only used with XCAP.
Local network subscription URI changed to <device-id>@
<local-network> (was anonymous@<local-network>). Having a
different Request URI for each device allows the network
management to track user agents and potentially manage bandwidth,
port allocation, etc.
Changed event package name from sip-profile to ua-profile per
discussion on the list and last IETF meeting.
Changed "local" profile type token to "local-network" per
discussion on the list and last IETF meeting.
Simplified "Vendor", "Model", "Version" event header parameters to
allow only quoted string values (previously allowed token as
well).
Clarified use of the term cache.
Added references for ABNF constructs.
Numerous editorial changes. Thanks Dale!
12.5. Changes from draft-ietf-sipping-config-framework-05.txt
Made HTTP and HTTPS profile transport schemes mandatory in the
profile delivery server. The subscribing device must implement
HTTP or HTTPS as the profile transport scheme.
Rewrote the security considerations section.
Divided references into Normative and Informative.
Minor edits throughout.
12.6. Changes from draft-ietf-sipping-config-framework-04.txt
Clarified usage of instance-id
Specify which event header parameters are mandatory or optional
and in which messages.
Included complete list of event header parameters in parameter
overview and IANA sections.
Removed TFTP reference as protocol for profile transport.
Added examples for discovery.
Added ABNF for all event header parameters.
Changed profile-name parameter back to profile-type. This was
changed to profile-name in 02 when the parameter could contain
either a token or a path. Now that the path is contained in the
separate parameter: "document", profile-type make more sense as
the parameter name.
Fixed some statements that should have and should not have been
normative.
Added the ability for the user agent to request that the default
user associated with the device be set/changed using the "network-
user" parameter.
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A bunch of editorial nits and fixes.
12.7. Changes from draft-ietf-sipping-config-framework-03.txt
Incorporated changes to better support the requirements for the use
of this event package with XCAP and SIMPLE so that we can have one
package (i.e. simple-xcap-diff now defines a content type not a
package). Added an additional profile type: "application". Added
document and app-id Event header parameters in support of the
application profile. Define a loose high level data model or
relationship between the four profile types. Tried to edit and fix
the confusing and ambiguous sections related to URI formation and
discovery for the different profile types. Better describe the
importance of uniqueness for the instance id which is used in the
user part of the device URI.
12.8. Changes from draft-ietf-sipping-config-framework-02.txt
Added the concept of the local network as a source of profile data.
There are now three separate logical sources for profile data: user,
device and local network. Each of these requires a separate
subscription to obtain.
12.9. Changes from draft-ietf-sipping-config-framework-01.txt
Changed the name of the profile-type event parameter to profile-name.
Also allow the profile-name parameter to be either a token or an
explicit URI.
Allow content indirection to be optional. Clarified the use of the
Accept header to indicate how the profile is to be delivered.
Added some content to the Iana section.
12.10. Changes from draft-ietf-sipping-config-framework-00.txt
This version of the document was entirely restructured and re-written
from the previous version as it had been micro edited too much.
All of the aspects of defining the event package are now organized in
one section and is believed to be complete and up to date with
[RFC3265].
The URI used to subscribe to the event package is now either the user
or device address or record.
The user agent information (vendor, model, MAC and serial number) are
now provided as event header parameters.
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Added a mechanism to force profile changes to be make effective by
the user agent in a specified maximum period of time.
Changed the name of the event package from sip-config to ua-profile
Three high level security approaches are now specified.
12.11. Changes from draft-petrie-sipping-config-framework-00.txt
Changed name to reflect SIPPING work group item
Synchronized with changes to SIP DHCP [RFC3361], SIP [RFC3261] and
[RFC3263], SIP Events [RFC3265] and content indirection [RFC4483]
Moved the device identity parameters from the From field parameters
to User-Agent header parameters.
Many thanks to Rich Schaaf of Pingtel, Cullen Jennings of Cisco and
Adam Roach of Estacado Systems for the great comments and input.
12.12. Changes from draft-petrie-sip-config-framework-01.txt
Changed the name as this belongs in the SIPPING work group.
Minor edits
12.13. Changes from draft-petrie-sip-config-framework-00.txt
Split the enrollment into a single SUBSCRIBE dialog for each profile.
The 00 draft sent a single SUBSCRIBE listing all of the desired.
These have been split so that each enrollment can be routed
differently. As there is a concept of device specific and user
specific profiles, these may also be managed on separate servers.
For instance in a nomadic situation the device might get its profile
data from a local server which knows the LAN specific profile data.
At the same time the user specific profiles might come from the
user's home environment profile delivery server.
Removed the Config-Expires header as it is largely superfluous with
the SUBSCRIBE Expires header.
Eliminated some of the complexity in the discovery mechanism.
Suggest caching information discovered about a profile delivery
server to avoid an avalanche problem when a whole building full of
devices powers up.
Added the User-Profile From header field parameter so that the device
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can request a user specific profile for a user that is different from
the device's default user.
13. References
13.1. Normative References
[I-D.ietf-sip-identity]
Peterson, J. and C. Jennings, "Enhancements for
Authenticated Identity Management in the Session
Initiation Protocol (SIP)", draft-ietf-sip-identity-06
(work in progress), October 2005.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
Extensions", RFC 2132, March 1997.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
A., Peterson, J., Sparks, R., Handley, M., and E.
Schooler, "SIP: Session Initiation Protocol", RFC 3261,
June 2002.
[RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation
Protocol (SIP): Locating SIP Servers", RFC 3263,
June 2002.
[RFC3265] Roach, A., "Session Initiation Protocol (SIP)-Specific
Event Notification", RFC 3265, June 2002.
[RFC3361] Schulzrinne, H., "Dynamic Host Configuration Protocol
(DHCP-for-IPv4) Option for Session Initiation Protocol
(SIP) Servers", RFC 3361, August 2002.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122,
July 2005.
[RFC4483] Burger, E., "A Mechanism for Content Indirection in
Session Initiation Protocol (SIP) Messages", RFC 4483,
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Internet-Draft SIPPING-CONFIG Framework March 2007
May 2006.
13.2. Informative References
[I-D.ietf-simple-xcap]
Rosenberg, J., "The Extensible Markup Language (XML)
Configuration Access Protocol (XCAP)",
draft-ietf-simple-xcap-12 (work in progress),
October 2006.
[I-D.ietf-simple-xcap-diff]
Rosenberg, J., "An Extensible Markup Language (XML)
Document Format for Indicating A Change in XML
Configuration Access Protocol (XCAP) Resources",
draft-ietf-simple-xcap-diff-04 (work in progress),
October 2006.
[RFC0959] Postel, J. and J. Reynolds, "File Transfer Protocol",
STD 9, RFC 959, October 1985.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol",
RFC 2131, March 1997.
[RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
[RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access
Protocol (v3): Technical Specification", RFC 3377,
September 2002.
[RFC3617] Lear, E., "Uniform Resource Identifier (URI) Scheme and
Applicability Statement for the Trivial File Transfer
Protocol (TFTP)", RFC 3617, October 2003.
Authors' Addresses
Daniel Petrie
SIPez LLC.
34 Robbins Rd
Arlington, MA 02476
USA
Email: dan.ietf AT SIPez DOT com
URI: http://www.SIPez.com/
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Sumanth Channabasappa (Editor)
CableLabs
858 Coal Creek Circle
Louisville, Co 80027
USA
Email: sumanth@cablelabs.com
URI: http://www.cablelabs.com/
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Petrie & Channabasappa, Ed. Expires September 2, 2007 [Page 56]
