SIPPING D. Petrie
Internet-Draft Pingtel Corp.
Expires: April 24, 2005 October 24, 2004
A Framework for Session Initiation Protocol User Agent Profile
Delivery
draft-ietf-sipping-config-framework-05.txt
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Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved.
Abstract
This document defines the application of a set of protocols for
providing profile data to SIP user agents. The objective is to
define a means for automatically providing profile data a user agent
needs to be functional without user or administrative intervention.
The framework for discovery, delivery, notification and updates of
user agent profile data is defined here. As part of this framework a
new SIP event package is defined here for the notification of profile
changes. This framework is also intended to ease ongoing
administration and upgrading of large scale deployments of SIP user
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agents. The contents and format of the profile data to be defined is
outside the scope of this document.
Table of Contents
1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1 Requirements Terminology . . . . . . . . . . . . . . . . . 4
2.2 Profile Delivery Framework Terminology . . . . . . . . . . 5
2.3 Overview . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Profile Change Event Notification Package . . . . . . . . . 8
3.1 Event Package Name . . . . . . . . . . . . . . . . . . . . 8
3.2 Event Package Parameters . . . . . . . . . . . . . . . . . 8
3.3 SUBSCRIBE Bodies . . . . . . . . . . . . . . . . . . . . . 12
3.4 Subscription Duration . . . . . . . . . . . . . . . . . . 12
3.5 NOTIFY Bodies . . . . . . . . . . . . . . . . . . . . . . 12
3.6 Notifier processing of SUBSCRIBE requests . . . . . . . . 13
3.7 Notifier generation of NOTIFY requests . . . . . . . . . . 14
3.8 Subscriber processing of NOTIFY requests . . . . . . . . . 14
3.9 Handling of forked requests . . . . . . . . . . . . . . . 15
3.10 Rate of notifications . . . . . . . . . . . . . . . . . 15
3.11 State Agents . . . . . . . . . . . . . . . . . . . . . . 15
3.12 Examples . . . . . . . . . . . . . . . . . . . . . . . . 15
3.13 Use of URIs to Retrieve State . . . . . . . . . . . . . 16
3.13.1 Device URIs . . . . . . . . . . . . . . . . . . . . 17
3.13.2 User and Application URIs . . . . . . . . . . . . . 18
3.13.3 Local Network URIs . . . . . . . . . . . . . . . . . 18
4. Profile Delivery Framework Details . . . . . . . . . . . . . 19
4.1 Discovery of Subscription URI . . . . . . . . . . . . . . 19
4.1.1 Discovery of Local Network URI . . . . . . . . . . . . 19
4.1.2 Discovery of Device URI . . . . . . . . . . . . . . . 20
4.1.3 Discovery of User and Application URI . . . . . . . . 22
4.2 Enrollment with Profile Server . . . . . . . . . . . . . . 22
4.3 Notification of Profile Changes . . . . . . . . . . . . . 23
4.4 Retrieval of Profile Data . . . . . . . . . . . . . . . . 23
4.5 Upload of Profile Changes . . . . . . . . . . . . . . . . 23
4.6 Usage of XCAP with the Profile Package . . . . . . . . . . 23
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . 26
5.1 SIP Event Package . . . . . . . . . . . . . . . . . . . . 26
6. Security Considerations . . . . . . . . . . . . . . . . . . 26
6.1 Symmetric Encryption of Profile Data . . . . . . . . . . . 27
7. Change History . . . . . . . . . . . . . . . . . . . . . . . 27
7.1 Changes from draft-ietf-sipping-config-framework-04.txt . 27
7.2 Changes from draft-ietf-sipping-config-framework-03.txt . 27
7.3 Changes from draft-ietf-sipping-config-framework-02.txt . 28
7.4 Changes from draft-ietf-sipping-config-framework-01.txt . 28
7.5 Changes from draft-ietf-sipping-config-framework-00.txt . 28
7.6 Changes from
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draft-petrie-sipping-config-framework-00.txt . . . . . . . 29
7.7 Changes from draft-petrie-sip-config-framework-01.txt . . 29
7.8 Changes from draft-petrie-sip-config-framework-00.txt . . 29
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 30
Author's Address . . . . . . . . . . . . . . . . . . . . . . 32
A. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 32
Intellectual Property and Copyright Statements . . . . . . . 33
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1. Motivation
Today all SIP user agent implementers use proprietary means of
delivering user, device, application and local network policy
profiles to the user agent. The profile delivery framework defined
in this document is intended to enable a first phase migration to a
standard means of providing profiles to SIP user agents. It is
expected that UA implementers will be able to use this framework as a
means of delivering their existing proprietary data profiles (i.e.
using their existing proprietary binary or text formats). This in
itself is a tremendous advantage in that a SIP environment can use a
single profile delivery server for profile data to user agents from
multiple implementers. Follow-on standardization activities can:
1. define a standard profile content format framework (e.g. XML
with namespaces [W3C.REC-xml-names11-20040204] or name-value
pairs [RFC0822]).
2. specify the content (i.e. name the profile data parameters, xml
schema, name spaces) of the data profiles.
One of the objectives of the framework described in this document is
to provide a start up experience similar to that of users of an
analog telephone. When you plug in an analog telephone it just works
(assuming the line is live and the switch has been provisioned).
There is no end user configuration required to make analog phone
work, at least in a basic sense. So the objective here is to be able
to take a new SIP user agent out of the box, plug it in or install
the software and have it get its profiles without human intervention
other than security measures. This is necessary for cost effective
deployment of large numbers of user agents.
Another objective is to provide a scalable means for ongoing
administration of profiles. Administrators and users are likely to
want to make changes to profiles.
Additional requirements for the framework defined in this document
are described in: [I-D.ietf-sipping-ua-prof-framewk-reqs],
[I-D.sinnreich-sipdev-req]
2. Introduction
2.1 Requirements Terminology
Keywords "MUST", "MUST NOT", "REQUIRED", "SHOULD", "SHOULD NOT" and
"MAY" that appear in this document are to be interpreted as described
in [RFC2119].
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2.2 Profile Delivery Framework Terminology
profile - data set specific to a user, device, user's application or
the local network.
device - software or hardware appliance containing one or more SIP
user agent.
profile content server - The server that provides the content of the
profiles using the protocol specified by the URI scheme.
notifier - As defined in [RFC3265] the SIP user agent server which
processes SUBSCRIBE requests for events and sends NOTIFY requests
with profile data or URI(s) that point to the data.
profile delivery server - The logical collection of the notifier and
the server which provides the contents of the notification either
directly in the NOTIFY requests or indirectly via profile URI(s).
2.3 Overview
The profile life cycle can be described by five functional steps.
These steps are not necessarily discrete. However it is useful to
describe these steps as logically distinct. These steps are named as
follows:
Discovery - discover a profile delivery server
Enrollment - enroll with the profile delivery server
Profile Retrieval - retrieve profile data
Profile Change Notification - receive notification of profile changes
Profile Change Upload - upload profile data changes back to the
profile delivery server
Discovery is the process by which a UA finds the address and port at
which it enrolls with the profile delivery server. As there is no
single discovery mechanism which will work in all network
environments, a number of discovery mechanisms are defined with a
prescribed order in which the UA tries them until one succeeds.
Enrollment is the process by which a UA makes itself known to the
profile delivery server. In enrolling the UA provides identity
information, requested profile type(s) and supported protocols for
profile retrieval. It also subscribes to a mechanism for
notification of profile changes. As a result of enrollment, the UA
receives the data or the URI for each of the profiles that the
profile delivery server is able to provide. Each profile type (set)
requires a separate enrollment or SUBSCRIBE session. A profile type
may represent one or more data sets (e.g. one profile data set for
each of a user's applications).
Profile Retrieval is the process of retrieving the content for each
of the profiles the UA requested.
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Profile Change Notification is the process by which the profile
delivery server notifies the UA that the content of one or more of
the profiles has changed. If the content is provided indirectly the
UA MAY retrieve the profile from the specified URI upon receipt of
the change notification.
Profile Change Upload is the process by which a UA or other entity
(e.g. OSS, corporate directory or configuration management server)
pushes a change to the profile data back up to the profile delivery
server.
This framework defines a new SIP event package [RFC3265] to solve
enrollment and profile change notification steps. This event package
defines everything but the mandatory content type. This makes this
event package abstract until the content type is bound. The profile
content type(s) will be defined outside the scope of this document.
It is the author's belief that it would be a huge accomplishment if
all SIP user agent used this framework for delivering their existing
proprietary profiles. Even though this does not accomplish
interoperability of profiles, it is a big first step in easing the
administration of SIP user agents. The definition of standard
profiles and data sets (see [I-D.petrie-sipping-profile-datasets] )
will enable interoperability as a subsequent step.
The question arises as to why SIP should be used for the profile
delivery framework. In this document SIP is used for only a small
portion of the framework. Other existing protocols are more
appropriate for transport of the profile contents (to and from the
user agent) and are suggested in this document. The discovery step
is simply a specified order and application of existing protocols.
SIP is only needed for the enrollment and change notification
functionality of the profile delivery framework. In many SIP
environments (e.g. carrier/subscriber and multi-site enterprise)
firewall, NAT and IP addressing issues make it difficult to get
messages between the profile delivery server and the user agent
requiring the profiles.
With SIP the users and devices already are assigned globally routable
addresses. In addition the firewall and NAT problems are already
presumably solved in the environments in which SIP user agents are to
be used. Therefore SIP is the best solution for allowing the user
agent to enroll with the profile delivery server, which may require
traversal of multiple firewalls and NATs. For the same reason the
notification of profile changes is best solved by SIP. It should be
noted that this document is scoped to providing profiles for devices
which contain one or more SIP user agents. This framework may be
applied to non-SIP devices, however more general requirements for
non-SIP devices are beyond the scope of this document.
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The content delivery server may be either in the public network or
accessible through a DMZ. The user agents requiring profiles may be
behind firewalls and NATs and many protocols, such as HTTP, may be
used for profile content retrieval without special consideration in
the firewalls and NATs (e.g. an HTTP client on the UA can typically
pull content from a server outside the NAT/firewall.).
A conscious separation of device, user, application and local network
profiles is made in this document. This is useful to provide
features such as hotelling as well as securing or restricting user
agent functionality. By maintaining this separation, a user may walk
up to someone else's user agent and direct that user agent to get the
new user's profile data. In doing so the user agent can replace the
previous user's profile data while still keeping the device's and the
local network's profile data which may be necessary for core
functionality and communication described in this document. The
local network profiles are relevant to a visiting device which gets
plugged in to a foreign network. The concept of the local network
providing profile data is useful to provide hotelling (described
above) as well as local policy data that may constrain the user or
device behavior relative to the local network. For example media
types and codecs may be constrained to reflect the network's
capabilities.
The separation of these profiles also enables the separation of the
management of the profiles. The user profile may be managed by a
profile delivery server operated by the user's ISP. The device
profile may be delivered from a profile delivery server operated by
the user's employer. The application profile(s) may be delivered
from the user's ASP. The local network profile may delivered by a
WIFI hotspot service provider. Some interesting services and
mobility applications are enabled with this separation of profiles.
A very high level data model is implied here with the separation of
these four profile types. Each profile type instance requires a
separate subscription to retrieve the profile. A loose hierarchy
exists mostly for the purpose of boot strapping and discovery or
formation of the profile URIs. No other meaning is implied by this
hierarchy. However the profile format and data sets to be defined
outside this document may define additional meaning to this
hierarchy. In the boot strapping scenario, a device straight out of
the box (software or hardware) does not know anything about it's user
or local network. The one thing that is does know is it's instance
id. So the hierarchy of the profiles exists as follows.
The instance id is used to form the user id part of the URI for
subscribing to the device profile. The device profile may contain a
default user AOR for that device. The default user AOR may then be
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used to retrieve the user profile. Applications to be used on the
device may be defined in the device and user profiles. The user's
AOR is also used to retrieve any application profiles for that user.
The local network profile is not referenced in any way from the
device, user, application profiles. It is subscribed to and
retrieved based upon a URI formed from the local network domain.
3. Profile Change Event Notification Package
This section defines a new SIP event package [RFC3265]. The purpose
of this event package is to send to subscribers notification of
content changes to the profile(s) of interest and to provide the
location of the profile(s) via content indirection
[I-D.ietf-sip-content-indirect-mech] or directly in the body of the
NOTIFY. Frequently the profiles delivered to the user agent are much
larger (e.g. several KB or even several MB) than the MTU of the
network. These larger profiles will cause larger than normal SIP
messages and consequently higher impact on the SIP servers and
infrastructure. To avoid the higher impact and load on the SIP
infrastructure, content indirection SHOULD be used if the profile is
large enough to cause packet fragmentation over the transport
protocol. The presence of the MIME type for content indirection
[I-D.ietf-sip-content-indirect-mech] in the Accept header indicates
that the user agent supports content indirection and that the profile
delivery server SHOULD use content indirection. Similarly the
content type for the differential notification of profile changes
[I-D.ietf-simple-xcap-package] may be used in the Accept header to
express support for receiving profile change deltas.
The MIME types or formats of profile to be delivered via this
framework are to be defined in the documents that define the profile
contents. These profile MIME types specified in the Accept header
along with the profile types specified in the Event header parameter
"profile-type" MAY be used to specify which profiles get delivered
either directly or indirectly in the NOTIFY requests. As this event
package does not specify the mandatory content type, this package is
abstract. The profile definition documents will specify the
mandatory content type to make a concrete event package.
3.1 Event Package Name
The name of this package is "sip-profile". This value appears in the
Event header field present in SUBSCRIBE and NOTIFY requests for this
package as defined in [RFC3265].
3.2 Event Package Parameters
This package defines the following new parameters for the event
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header: "profile-type", "vendor", "model", "version", "effective-by",
"document", "app-id", "network-user". The "effective-by" parameter
is for use in NOTIFY requests only. The "effected-by" parameter is
ignored if it appears in a SUBSCRIBE request. The others parameters
are for use in the SUBSCRIBE request and are ignored if they appear
in NOTIFY requests.
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. Using a token in this
parameter allows the URI semantics for retrieving the profiles to be
opaque to the subscribing user agent. All it needs to know is the
token value for this parameter. This document defines four logical
types of profiles and their token names. The contents or format of
the profiles is outside the scope of this document.
The four types of profiles define here are "device", "user",
"application" and "local". 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(s) that are specific to the device or user agent. 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. Specifying "application" 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's applications. Specifying "local" type profile
indicates the desire for profiles data (URI when content indirection
is used) specific to the local network. The device, user,
application or local network is identified in the URI of the
SUBSCRIBE request. 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.
Profile-type = "profile-type" HCOLON profile-value
profile-value = profile-types / token
profile-types = "device" / "user" / "application" / "local"
The "device", "user", "application" or "local" token in the
profile-type parameter may represent a class or set of profile
properties. As standards are defined for specific profile
contents related to the user device or local network, it may be
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 filter or indicate what data sets of the profile
are desired.
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The rational for the separation of user, device, application and
local network type profiles is provided in Section 2.3. It should be
noted that any of the types may result in zero or more profiles or
URIs being provided in the NOTIFY request. As discussed, a default
user may be assigned to a device. The default user's AOR may in turn
be used as the URI to SUBSCRIBE to the "user" and "application"
profile types.
The data provided in the four types of profiles may overlap. As an
example the codecs that a user prefers to use, the codecs that the
device supports (and the enterprise or device owner wishes to use),
the codecs that the local network can support (and the network
operator wishes to allow) all may overlap in how they are specified
in the three corresponding profiles. This policy of merging the
constraints across the multiple profile types can only unambiguously
be defined along with the profile format and syntax. This is out of
scope for this document.
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.
These parameters are useful to the profile delivery server 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 user
agent. This gives the profile delivery server the ability to
compensate for or take advantage of the differences.
Vendor = "vendor" HCOLON token / quoted-string
Model = "model" HCOLON token / quoted-string
Version = "version" HCOLON token / quoted-string
The "network-user" parameter MAY be used when subscribing for device
and local network profiles. When the profile-type is "device" or
"local" , the SUBSCRIBE URI addresses the device or local network
profile delivery server. It by design cannot indicate the user's
identity. The "network-user" parameter is used to indicate the
user's AOR. The SUBSCRIBE server may authenticate the subscriber to
verify this AOR. If the value of the "profile-type" parameter is not
"device" or "local", the "network-user" parameter has no defined
meaning and is ignored.
Network-User = "network-user" HCOLON name-addr / addr-spec
When the profile-type is "device", the user agent MAY set the
"network-user" parameter to the user's AOR. This is an indication to
the profile delivery server to set or change the association of the
default user with the device indicated in the SUBSCRIBE URI. If the
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profile delivery server implements and allows this policy of setting
the default user with a device, the user agent can utilize this
mechanism to allow a user to login and make the user agent and user
association stick.
In the case where the profile-type is "local", the user agent MAY set
the "network-user" parameter. If the user has special privileges
beyond that of an anonymous user in the local network, the
"network-user" parameter identifies the user to the local network.
The value of this parameter is the user's address of record.
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. 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 profile delivery server 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.
Effective-By = "effective-by" HCOLON 1*DIGIT
The "document" parameter is used to specify a relative URI for a
specific profile document that the user agent wishes to retrieve and
to receive change notification. This is particularly useful for
profile content like XCAP [I-D.ietf-simple-xcap] where there is a
well defined URI schema and the user agent knows the specific content
that it wants. The "document" parameter value syntax is a quoted
string. For more details on the use of this package with XCAP see
Section 4.6. The "document" parameter MAY be set in SUBSCRIBE
requests. It is ignored in all other messages.
Document = "document" HCOLON quoted-string
The "app-id" parameter MAY be set when the "profile-type" parameter
value is "application". The "app-id" indicates that the user agent
wishes to retrieve the profile data or URI and change notification
for the application profile data for the specific application
indicated in the value of the "app-id" parameter. The "app-id"
parameter value is a token. The "app-id" parameter has meaning only
in SUBSCRIBE requests when the "profile-type" Event header parameter
is set to "application". The "app-id" parameter is ignored in all
other messages.
App-Id = "app-id" HCOLON token / quoted-string
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SUBSCRIBE request Event header examples:
Event: sip-profile;profile-type=device;
vendor=acme;model=Z100;version=1.2.3
Event: sip-profile;profile-type="user";document=
"http://example.com/services/user-profiles/users/freds.xml";
vendor=premier;model=trs8000;version=5.5
NOTIFY request Event header examples:
Event:sip-profile;effective-by=0
Event:sip-profile;effective-by=3600
3.3 SUBSCRIBE Bodies
This package defines no new use of the SUBSCRIBE request body.
Future follow on documents may specify a filter-like mechanism using
etags to minimize the delivery or notification of profiles where the
user agent already has a current version.
3.4 Subscription Duration
As the presence (or lack of) a device or user agent it not very time
critical to the functionality of the profile delivery server, it is
recommended that default subscription duration be 86400 seconds (one
day).
3.5 NOTIFY Bodies
The size of profile content is likely to be hundreds to several
thousand bytes in size. Frequently even with very modest sized SDP
bodies, SIP messages get fragmented causing problems for many user
agents. For this reason if the Accept header of the SUBSCRIBE
included the MIME type: message/external-body indicating support for
content indirection the profile delivery server SHOULD use content
indirection [I-D.ietf-sip-content-indirect-mech] in the NOTIFY body
for providing the profiles.
When delivering profiles via content indirection the profile delivery
server MUST include the Content-ID defined in
[I-D.ietf-sip-content-indirect-mech] for each profile URI. This is
to avoid unnecessary download of the profiles. Some user agents are
not able to make a profile effective without rebooting or restarting.
Rebooting is something to be avoided on a user agent performing
services such as telephony. In this way the Content-ID allows the
user agent to avoid unnecessary interruption of service as well. The
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Content-Type MUST be specified for each URI.
Initially user agent implementers may use a proprietary content
type for the profiles retrieved from the URI(s). This is a good
first step towards easing the management of user agents. Standard
profile contents, content type and formats will need to be defined
for true interoperability of profile delivery. The specification
of the content is out of the scope of this document.
Likewise the URI scheme [RFC2396] used in the content indirection is
outside the scope of this document. This document is agnostic to the
URI schemes as the profile content may dictate what is required. It
is expected that FTP [RFC0959], HTTP [RFC2616], HTTPS [RFC2818],
LDAP [RFC3377], XCAP [I-D.ietf-simple-xcap] and other URI schemes are
supported by this package and framework.
3.6 Notifier processing of SUBSCRIBE requests
The general rules for processing SUBSCRIBE requests [RFC3265] apply
to this package. If content indirection is used for delivering the
profiles, the notifier does not need to authenticate the subscription
as the profile content is not transported in the SUBSCRIBE or NOTIFY
transaction messages. With content indirection only URIs are
transported in the NOTIFY request which may be secured using the
techniques in Section 6. If content indirection is not used, SIPS
with SIP authentication SHOULD be used.
The behavior of the profile delivery server is left to the
implementer. The profile delivery server may be as simple as a SIP
SUBSCRIBE UAS and NOTIFY UAC front end to a simple HTTP server
delivering static files that are hand edited. At the other extreme
the profile delivery server can be part of a configuration management
system that integrates with a corporate directory and IT system or
carrier operations support systems, where the profiles are
automatically generated. The design of this framework intentionally
provides the flexibility of implementation from simple/cheap to
complex/expensive.
If the user or device is not known to the profile delivery server,
the implementer MAY accept the subscription or reject it. It is
recommended that the implementer accept the subscription. It is
useful for the profile delivery server to maintain the subscription
as an administrator may add the user or device to the system,
defining the profile contents. This allows the profile delivery
server to immediately send a NOTIFY request with the profile URIs.
If the profile delivery server does not accept the subscription from
an unknown user or device, the administer or user must manually
provoke the user agent to reSUBSCRIBE. This may be difficult if the
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user agent and administrator are at different locations.
When the Event header "profile-type" is "device" and the user agent
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 device indicated in the SUBSCRIBE URI. This is an
implementation or policy decision. The profile delivery server
SHOULD authenticate the user for the SUBSCIRBE request before
effecting the default user indicated in the "network-user" parameter.
3.7 Notifier generation of NOTIFY requests
As in [RFC3265], the profile delivery server MUST always send a
NOTIFY request upon accepting a subscription. If the device or user
is unknown to the profile delivery server and it chooses to accept
the subscription, the implementer has two choices. A NOTIFY MAY be
sent with no body or content indirection containing the profile
URI(s). Alternatively a NOTIFY MAY be sent with a body or content
indirection containing URI(s) pointing to a default data set. The
data sets provided may allow for only limited functionality of the
user agent (e.g. a phone user agent with data to enable calls to
help desk and emergency services.). This is an implementation and
business policy decision for the profile delivery server.
If the URI in the SUBSCIRBE request is a known identity and
provisioned with the requested profile type (i.e. as specified in
the profile-type parameter of the Event header), the profile delivery
server SHOULD send a NOTIFY with profile data or content indirection
(if the content type was included in the Accept header) containing
the URI for the profile.
A user agent can provide hotelling by collecting a user's AOR and
credentials needed to SUBSCRIBE and retrieve the user's profiles.
Hotelling functionality is achieved by subscribing to the user's AOR
and specifying the "user" profile type. This same mechanism can also
be used to secure a user agent, requiring a non-mobile user to login
to enable functionality beyond the default user's restricted
functionality.
The profile delivery server may specify when the new profiles must be
made effective by the user agent. The profile delivery server MAY
specify a maximum time in seconds (zero or more), in the
"effective-by" event header parameter, by which the user agent is
required to make the new profiles effective for all dialogs.
3.8 Subscriber processing of NOTIFY requests
The user agent subscribing to this event package MUST adhere to the
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NOTIFY request processing behavior specified in [RFC3265]. The user
agent MUST attempt to make the profiles effective within the time in
seconds given in the "effective-by" Event header parameter if present
in the NOTIFY request (see Section 3.7). By default the user agent
makes the profiles effective as soon as it thinks that it is
non-obtrusive. Profile changes SHOULD affect behavior on all new
dialogs which are created after the notification, but may not be able
to affect existing dialogs. The user agent SHOULD use one of the
techniques specified in Section 6 to securely retrieve the profiles.
3.9 Handling of forked requests
This event package allows the creation of only one dialog as a result
of an initial SUBSCRIBE request. The techniques to achieve this are
described in section 4.4.9 of [RFC3265].
3.10 Rate of notifications
It is anticipated that the rate of change for user and device
profiles will be very infrequent (i.e. days or weeks apart). For
this reason no throttling or minimum period between NOTIFY requests
is specified for this package.
3.11 State Agents
State agents are not applicable to this event package.
3.12 Examples
Example SUBSCRIBE and NOTIFY request using content indirection:
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SUBSCRIBE sip:ff00000036c5@acme.com SIP/2.0
Event: sip-profile;profile-type=device;vendor=acme;
model=Z100;version=1.2.3
From: sip:ff00000036c5@acme.com;tag=1234
To: sip:ff00000036c5@acme.com;tag=abcd
Call-ID: 3573853342923422@10.1.1.44
CSeq: 2131 SUBSCRIBE
Contact: sip:ff00000036c5@10.1.1.44
Via: SIP/2.0/TCP 10.1.1.41;
branch=z9hG4bK6d6d35b6e2a203104d97211a3d18f57a
Accept: message/external-body, application/z100-device-profile
Content-Length: 0
NOTIFY sip:ff00000036c5@10.1.1.44 SIP/2.0
Event: sip-profile;effective-by=3600
From: sip:ff00000036c5@acme.com;tag=abcd
To: sip:ff00000036c5@acme.com;tag=1234
Call-ID: 3573853342923422@10.1.1.44
CSeq: 321 NOTIFY
Via: SIP/2.0/UDP 192.168.0.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d1
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary=boundary42
Content-Length: ...
--boundary42
Content-Type: message/external-body;
access-type="URL";
expiration="Mon, 24 June 2002 09:00:00 GMT";
URL="http://www.example.com/devices/ff00000036c5";
size=1234
Content-Type: application/z100-device-profile
Content-ID: <39EHF78SA@example.com>
--boundary42--
3.13 Use of URIs to Retrieve State
The URI for the SUBSCRIBE request is formed differently depending
upon which profile type the subscription is for. This allows the
different profile types to be potentially managed by different
profile delivery servers (perhaps even operated by different
entities).
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3.13.1 Device URIs
The URI for the "device" type profile (device URI) is base upon the
identity of the device. The device URI MUST be unique over time and
space for all devices and implementations. If an instance id is used
as the user part of the device URI, it SHOULD remain the same for the
lifetime of the user agent. The device URI is used to identify which
profile is associated with a specific instance of a user agent.
If the user agent were to change its device URI, the profile
delivery server would lose its association between the profile and
the device. This would also make it difficult for the profile
delivery server to track user agents under profile management.
The profile delivery server may decide to provide the same device
profile to all devices of the same vendor, model and version.
However this is a implementation choice on the profile delivery
server. The subscribing device has no way of knowing the profile
difference. As an example the device profile for similar devices
may differ with properties such as the default user. This is how
the bootstrapping mechanism works as described in Section 4.1.3.
The URI for the device type profile should use a unique identifier as
the user portion of the URI. The host and port portion of the URI is
set to that of the domain or address of the profile deliver server
which manages that user agent. A means of discovering the host and
port portion is discussed in Section 4.1. Like the call-id header
value in SIP, consistency of the format across implementations is
less important than the guarantee of uniqueness across all instances.
There is a administration aspect of the unique identifier, that makes
it desirable for the id to be obtainable or predictable prior to
installation of the device (hard or soft). Also from a human factors
perspective, ids that are easily distinguished and communicated will
make the administrators job a little easier. Two approaches are
suggested for constructing a unique identifier to be used in the user
portion of the device URI.
The MAC address of the device may be used if there will always be
no more than one user agent using that MAC address over time (e.g.
a dedicate telephone appliance). The MAC address may not be used
if more than one user agent instance exists or use the same MAC
address (e.g. multiple instances of a softphone may run on a
general purpose computing device). The advantage of the MAC
address is that many vendors put bar codes on the device with the
actual MAC address on it. A bar code scanner is a convenient
means of collecting the instance id for input and provisioning on
the profile delivery server. If the MAC address is used, it is
recommended that the MAC address is rendered in all lower case
with no punctuation for consistency across implementations. For
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example a device managed by sipuaconfig.example.com using its MAC
address to form the device URI might look like:
sip:00df1e004cd0@sipuaconfig.example.com.
For devices where there is no MAC address or the MAC address is
not unique to an instance of a user agent (e.g. multiple
softphones on a computer or a gateway with multiple logical user
agents) it is recommended that a URN [RFC2141] is used as the user
portion of the device URI. The approach to defining a user agent
instance ID for GRUU [I-D.ietf-sip-gruu] should be considered.
When constructing the instance id the implementer should also
consider that a human may need to manual enter the instance id to
provision the device in the profile delivery server (i.e. longer
strings are more error prone in data entry). When the URN is used
as the user part of URI, it MUST be URL escaped. The ":" is not a
legal character (without being escaped) in the user part of a
name-addr. For example the instance ID:
urn:uuid:f81d4fae-7dec-11d0-a765-00a0c91e6bf6 would be escaped to
look as follows in a URI:
sip:urn%3auuid%3af81d4fae-7dec-11d0-a765-00a0c91e6bf6@example.com.
Soft user agents are likely to need to use this approach due to
the multi-user nature of general purpose computers. The software
installer program might generate the uuid as part of the install
process so that it remains persistent for the installation. It
may also be desirable that any upgrades of the software maintain
the unique id. However these are all implementation choices.
3.13.2 User and Application URIs
The URI for the "user" and "application" type profiles is based upon
the identity of the user. The user's address of record (AOR) is used
as the URI in the SUBSCRIBE request. A new user agent or device may
not know the user's AOR. The user's AOR may be obtained as part of a
default user property in the device profile. Alternatively the user
agent may prompt the user for an AOR and credentials to be used to
authenticate the request. This can provide a login and/or hotelling
feature on the user agent. The user agent may be pre-provisioned
with the user's AOR or provided as information on a SIM or flash key.
These are only examples not an exhaustive list of sources for the
user AOR.
3.13.3 Local Network URIs
The URI for the "local" type profile is based upon the identity of
the local network. When subscribing to the local network profile,
the user part of the URI is "anonymous". The host and port part of
the URI is the local network name/domain. The discovery of the local
network name or domain is discussed in Section 4.1. The user agent
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may provide the user's AOR as the value to the "network-user" event
header parameter. This is useful if the user has privileges in the
local network beyond those of the default user. The profile delivery
server SHOULD authenticate the user before providing the profile if
additional privileges are granted. Example URI:
sip:ananymous@example.com
4. Profile Delivery Framework Details
The following describes how different functional steps of the profile
delivery framework work. Also described here is how the event
package defined in this document provides the enrollment and
notification functions within the framework.
4.1 Discovery of Subscription URI
The discovery approach varies depending upon which profile type URI
is to be discovered. The order of discovery is important in the boot
strapping situation as user agent may not have any information
provisioned. The local network profile should be discovered first as
it may contain key information such as how to traverse a NAT/firewall
to get to outside services (e.g. the user's profile delivery
server). The device profile URI should be discovered next. The
device profile may contain the default user's AOR or firmware/
software information that should be updated first before proceeding
with the discovery process. The user and application profile
subscription URIs should be discovered last. The URIs are formed
differently for each of the profile types. This is to support the
delegation of the profile management to potentially four different
entities. However all four profile types may be provided by the same
entity. As the user agent has no way of knowing whether the profiles
are provide by one or more different profile delivery servers ahead
of time, it must subscribe to all four profile types in separate
SUBSCRIBE requests to get the profiles.
4.1.1 Discovery of Local Network URI
The "discovered" host for the "local" profile subscription URI is the
local IP network domain for the user agent, either provisioned as
part of the device's static network configuration or discovered via
DHCP. The local network profile subscription URI should not be
cached as the user agent may move from one local network to the
other. The user agent should perform the local network discovery
every time it starts up or network connectivity is regained.
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For example: The user agent requested and received the local
domain name via DHCP: loganairport.com. The local network URI
would look like: sip:anonymous@loganairport.com. The user agent
should send this request using the normal SIP locating mechanisms
defined in [RFC3263]. The Event header would look like the
following if the user agent decided to provide the user's AOR:
sip:alice@example.com as Alice may have a prior arrangement with
the local network operator giving her special policy privileges:
Event: sip-profile;profile-type=local;
network-user=sip:alice@example.com
4.1.2 Discovery of Device URI
The discovery function is needed to bootstrap user agents to the
point of knowing where to enroll with the profile delivery server.
Section 3.13.1 describes how to form the device URI used to send the
SUBSCRIBE request for enrollment. However the bootstrapping problem
for the user agent (out of the box) is what to use for the host and
port in the device URI. Due to the wide variation of environments in
which the enrolling user agent may reside (e.g. behind residential
router, enterprise LAN, WIFI hotspot, ISP, dialup modem) and the
limited control that the administrator of the profile delivery
server (e.g. enterprise, service provider) may have over that
environment, no single discovery mechanism works everywhere.
Therefore a number of mechanisms should be tried in the specified
order: SIP DHCP option [RFC3361], SIP DNS SRV [RFC3263], DNS A record
and manual. The user agent may be pre-provisioned with the host and
port (e.g. service providers may pre-provision a device before
sending it to a subscriber, provide a SIM or flash key, etc.) in
which case this discovery mechanism is not needed. Before performing
the discovery steps, the user agent should provide a means to skip
the discovery stage and manually enter the device URI host and port.
In addition the user agent should allow the user to accept or reject
the discovered host and port, in case an alternate to the discovered
host and port are desired.
1. The first discovery mechanism that should be tried to construct
the device SUBSCRIBE URI, as described in Section 3.13.1, is to
use the host and port of the out bound proxy discovered by the
SIP DHCP option as described in [RFC3361]. If the SIP DHCP
option is not provided in the DHCP response; or no SIP response
is received for the SUBSCRIBE request; or a SIP failure response
other than for authorization is received for the SUBSCRIBE
request to the sip-profile event, the next discovery mechanism
should be tried.
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For example: Consider a dedicated hardware device with a
single user agent having the MAC address: abc123efg456. The
user agent sends a DHCP request including the request for the
DHCP option for SIP: 120 (see [RFC3361]). If the DHCP
response includes an answer for option 120, then the DNS name
or IP address included is used in the host part of the device
URI. For this example let's assume: example.com. The device
URI would look like: sip:abc123efg456@example.com. The user
agent should send this request using the normal SIP locating
mechanisms defined in [RFC3263]. If the response fails then,
the next discovery mechanism is tried.
2. The local IP network domain for the user agent, either configured
or discovered via DHCP, should be used with the technique in
[RFC3263] to obtain a host and port to use in the SUBSCRIBE URI.
If no SIP response or a SIP failure response other than for
authorization is received for the SUBSCRIBE request to the
sip-profile event, the next discovery mechanism should be tried.
For example: The user agent requested and received the local
domain name (option 15) in the DHCP response:
boston.example.com. The device URI would look like:
sip:abc123efg456@boston.example.com. The user agent should
send this request using the normal SIP locating mechanisms
defined in [RFC3263]. If the response fails then, the next
discovery mechanism is tried.
3. The fully qualified host name constructed using the host name
"sipuaconfig" and concatenated with the local IP network domain
(as provided via DHCP or provisioned) should be tried next using
the technique in [RFC3263] to obtain a host and port to use in
the SUBSCRIBE URI. If no SIP response or a SIP failure response
other than for authorization is received for the SUBSCRIBE
request to the sip-profile event, the next discovery mechanism
should be tried.
For example: The user agent requested and received the local
domain name via DHCP as in the above example:
boston.example.com. The device URI would look like:
sip:abc123efg456@sipuaconfig.boston.example.com. The user
agent should send this request using the normal SIP locating
mechanisms defined in [RFC3263]. If the response fails then,
the next discovery mechanism is tried.
4. If all other discovery techniques fail, the user agent MUST
provide a manual means for the user to enter the host and port
used to construct the SUBSCRIBE URI.
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Once a user agent has successfully discovered, enrolled and received
a NOTIFY response with profile data or URI(s), the user agent should
cache the device profile SUBSCRIBE URI to avoid having to rediscover
the profile delivery server again in the future. Caching of the
device URI is necessary when the user agent is likely to move to
different local network domains as the local network may not be the
provider for the device's profile. The user agent should not cache
the device URI until it receives a NOTIFY with profile data or
URI(s). The reason for this is that a profile delivery server may
send 202 responses to SUBSCRIBE requests and NOTIFY responses to
unknown user agent (see Section 3.6) with no URIs. Until the profile
delivery server has sent a NOTIFY request with profile data or
URI(s), it has not agreed to provide profiles.
To illustrate why the user agent should not cache the device
profile SUBSCRIBE URI until profile data or URI(s) are provided in
the NOTIFY, consider the following example: a user agent running
on a laptop plugged into a visited LAN in which a foreign profile
delivery server is discovered. The profile delivery server never
provides profile URIs in the NOTIFY request as it is not
provisioned to accept the user agent. The user then takes the
laptop to their enterprise LAN. If the user agent cached the
SUBSCRIBE URI from the visited LAN (which did not provide
profiles), when subsequently placed in the enterprise LAN which is
provisioned to provide profiles to the user agent, the user agent
would not attempt to discover the profile delivery server.
4.1.3 Discovery of User and Application URI
The default user's AOR from the device profile (if provided) may then
be used to subscribe to the "user" and "application" profiles. The
user's AOR may be prepovisioned or provided via SIM or flash key,
etc. Alternatively the user's AOR to be used for the "user" and
"application" subscription URI, may be "discovered" manually by
prompting the user. This "discovered" URI for the user and
application profile subscription may be cached.
4.2 Enrollment with Profile Server
Enrollment is accomplished by subscribing to the event package
described in Section 3. The enrollment process is useful to the
profile delivery server as it makes the server aware of user agents
to which it may deliver profiles (those user agents the profile
delivery server is provisioned to provide profiles to; those present
to which the server may provide profiles in the future; and those
that the server can automatically provide default profiles). It is
an implementation choice and business policy as to whether the
profile delivery server provides profiles to user agents that it is
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not explicitly provisioned to do so. However the profile delivery
server SHOULD accept (with 2xx response) SUBSCRIBE requests from any
user agent as explained in Section 3.5.
4.3 Notification of Profile Changes
The NOTIFY request in the sip-profile event package serves two
purposes. First it provides the user agent with a means to obtain
the profile data directly or via URI(s) for desired profiles without
requiring the end user to manually enter them. It also provides the
means for the profile delivery server to notify the user agent that
the content of the profiles has changed and should be made effective.
Optionally the differential changes may be obtained by including the
content-type: "application/xcap-diff+xml" defined in
[I-D.ietf-simple-xcap-package] in the Accept header of the SUBSCRIBE
request.
4.4 Retrieval of Profile Data
The user agent retrieves its needed profile(s) directly or via the
URI(s) provided in the NOTIFY request as specified in Section 3.5.
The profile delivery server SHOULD secure the content of the profiles
using one of the techniques described in Section 6. The user agent
SHOULD make the new profiles effective in the timeframe described in
Section 3.2.
The contents of the profiles SHOULD be cached by the user agent.
This it to avoid the situation where the content delivery server is
not available, leaving the user agent non-functional.
4.5 Upload of Profile Changes
The user agent or other service MAY push changes up to the profile
delivery server using the technique appropriate to the profile's URL
scheme (e.g. HTTP PUT method, FTP put command). The technique for
pushing incremental or atomic changes MUST be described by the
specific profile data framework. A means for pushing changes up into
the profile delivery server for XCAP is defined in
[I-D.ietf-simple-xcap].
4.6 Usage of XCAP with the Profile Package
This framework allows for the usage of several different protocols
for the retrieval of profiles. One protocol which is suitable is
XCAP [I-D.ietf-simple-xcap], which allows for HTTP URIs to represent
XML documents, elements and attributes. XCAP defines a specific
hierarchy for how documents are organized. As a result, it is
necessary to discuss how that organization relates to the rough data
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model presented here.
When a user or device enrolls with a SUBSCRIBE request, the request
UIR will contain some kind of identifying information for that user
or device. This identity is mapped to an XCAP User ID (XUID) based
on an implementation specific mapping. The "profile-type" along with
the "app-id" Event header parameters specify the specific XCAP
application usage.
In particular, when the Event header parameter "profile-type" is
"application", the "app-id" MAY be included to contain the XCAP
Application Unique ID (AUID). When the "profile-type" is
"application", but the "app-id" parameter is absent, this specifies
that the user wishes to SUBSCRIBE to all documents for all
application usages associated with the user in the request-uri. This
provides a convenient way for a single subscription to be used to
obtain all application data. The XCAP root is determined by a local
mapping.
When the "profile-type" is "device", or "user" or "local", this maps
to an AUID and document selector for representing device, user and
local-network data, respectively. The mapping is a matter of local
policy. This allows different providers to use different XCAP
application usages and document schemas for representing these
profiles, without having to configure the device with the specific
AUID which is being used.
Furthermore, when the "document" attribute is present, it identifies
a specific document that is being requested. If the "profile-type"
is "application", the "app-id" MAY be present as well if the
"document" relative path does not indicate the specific application
profile. The "document" attribute then specifies a relative path
reference. Its first path segment is either "global", specifying
global data, or "user", specifying user data for the user in the
request URI. The next path segment identifies the path in the global
directory or the user's home directory. For "profile-type"
"application", if "app-id" is not present the next path segment (i.e.
after "global" or the user's home directory segment) MAY indicate the
XCAP Application Unique ID (AUID) if the user agent wishes to
subscribe to a specific application profile.
For example, consider a phone with an instance ID of
urn:uuid:00000000-0000-0000-0000-0003968cf920. To obtain its device
profile, it would generate a SUBSCRIBE that contain the following
Request-Line and Event header:
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SUBSCRIBE
sip:urn%3auuid%3a00000000-0000-0000-0000-0003968cf920@example.com
SIP/2.0
Event: sip-profile;profile-type=device
If the profile data is stored in an XCAP server, the server would map
the "device" profile to an application usage and document selector
based on local policy. If this mapping specifies the AUID
"vendor2-device-data" and a document called "index" within the user
directory, the corresponding HTTP URI for the document is:
http://xcap.example.com/root/vendor2-device-data/users/
urn%3auuid%3a00000000-0000-0000-0000-0003968cf920/index
and indeed, if a content indirection is returned in a NOTIFY, the URL
would equal this.
That user profile might specify the user identity (as a SIP AOR) and
their application-usages. From that, the device can enroll to learn
about its application data. To learn about all of the data:
SUBSCRIBE sip:user-aor@example.com SIP/2.0
Event: sip-profile;profile-type=application
The server would map the request URI to an XUI (user-aor, for
example) and the xcap root based on local policy. If there are two
AUIDs, "resource-lists" [I-D.ietf-simple-xcap-list-usage] and
"rls-services" [I-D.ietf-simple-xcap-list-usage], this would result
in a subscription to all documents within:
http://xcap.example.com/root/rls-services/users/user-aor
http://xcap.example.com/root/resource-lists/users/user-aor
The user would not be subscribed to the global data for these two
application usages, since that data is not important for users.
However, the user/device could be made aware that it needs to
subscribe to a specific document. In that case, its subscribe would
look like:
SUBSCRIBE sip:user-aor@example.com SIP/2.0
Event: sip-profile;profile-type=application;app-id=resource-lists
;document="global/index"
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this would result in a subscription to the single global document for
resource-lists.
In some cases, these subscriptions are to a multiplicity of
documents. In that case, the notification format will need to be one
which can indicate what document has changed. This includes content
indirection, but also the xcap diff format
[I-D.ietf-simple-xcap-package].
5. IANA Considerations
There are several IANA considerations associated with this
specification.
5.1 SIP Event Package
This specification registers a new event package as defined in
[RFC3265]. The following information required for this registration:
Package Name: sip-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).
Person to Contact: Daniel Petrie dpetrie AT pingtel.com
New event header parameters: profile-type, vendor, model, version,
effective-by, document, app-id, network-user
6. Security Considerations
Profiles may contain sensitive data such as user credentials. The
protection of this data depends upon how the data is delivered. If
the data is delivered in the NOTIFY body, SIP authentication MUST be
used for SUBSCRIPTION and SIPS and/or S/MIME MAY be use to encrypt
the data. If the data is provided via content indirection, SIP
authentication is not necessary for the SUBSCRIBE request. With
content indirection the data is protected via the authentication,
authorization and encryption mechanisms provided by the profile URL
scheme. Use of the URL scheme security mechanisms via content
indirection simplifies the security solution as the SIP event package
does not need to authenticate, authorize or protect the contents of
the SIP messages. Effectively the profile delivery server can safely
provide profile URI(s) to anyone. The profile content is protected
via the URL scheme transport mechanisms for authentication,
authorization and encryption (e.g. via HTTPS). HTTPS provides two
possible mechanisms for authentication: 1) the device may have a
certificate that the profile deliver server can request in the TLS
setup; or 2) the profile deliver server may use HTTP authentication
[RFC2617] with the device or users credentials.
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6.1 Symmetric Encryption of Profile Data
If the transport for the URL scheme used for content indirection does
not provide authentication, authorization or encryption, a technique
to provide this is to encrypt the profiles on the content delivery
server using a symmetric encryption algorithm using a shared key.
The encrypted profiles are delivered by the content delivery server
via the URIs provided in the NOTIFY requests. Using this technique
the profile delivery server does not need to provide authentication
or authorization for the retrieval as the profiles are obscured. The
user agent must obtain the username and password from the user or
other out of band means to generate the key and decrypt the profiles.
7. Change History
Many thanks to those who contributed and commented on the many
iterations of this document. Detailed input was provided by Jonathan
Rosenberg from Dynamicsoft, Henning Schulzrinne from Columbia U.,
Cullen Jennings from Cisco, Rohan Mahy from Cisco, Rich Schaaf from
Pingtel, Volker Hilt from Bell Labs, Hisham khartabil from Nokia,
Henry Sinnreich from MCI, Martin Dolly from ATT Labs, and John Elwell
from Siemens.
7.1 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 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.
A bunch of editorial nits and fixes.
7.2 Changes from draft-ietf-sipping-config-framework-03.txt
Incorporated changes to better support the requirements for the use
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of this event package with XCAP and SIMPLE so that we can have one
package (i.e. simple-xcap-package 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.
7.3 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.
7.4 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.
7.5 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.
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 sip-profile
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Three high level security approaches are now specified.
7.6 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
[I-D.ietf-sip-content-indirect-mech]
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 Dyamicsoft for the great comments and input.
7.7 Changes from draft-petrie-sip-config-framework-01.txt
Changed the name as this belongs in the SIPPING work group.
Minor edits
7.8 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 roaming 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
can request a user specific profile for a user that is different from
the device's default user.
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8 References
[I-D.ietf-simple-xcap]
Rosenberg, J., "The Extensible Markup Language (XML)
Configuration Access Protocol (XCAP)",
draft-ietf-simple-xcap-04 (work in progress), October
2004.
[I-D.ietf-simple-xcap-list-usage]
Rosenberg, J., "Extensible Markup Language (XML) Formats
for Representing Resource Lists",
draft-ietf-simple-xcap-list-usage-04 (work in progress),
October 2004.
[I-D.ietf-simple-xcap-package]
Rosenberg, J., "An Extensible Markup Language (XML)
Document Format for Indicating Changes in XML
Configuration Access Protocol (XCAP) Resources",
draft-ietf-simple-xcap-package-02 (work in progress), July
2004.
[I-D.ietf-sip-content-indirect-mech]
Burger, E., "A Mechanism for Content Indirection in
Session Initiation Protocol (SIP) Messages",
draft-ietf-sip-content-indirect-mech-05 (work in
progress), October 2004.
[I-D.ietf-sip-gruu]
Rosenberg, J., "Obtaining and Using Globally Routable User
Agent (UA) URIs (GRUU) in the Session Initiation Protocol
(SIP)", draft-ietf-sip-gruu-02 (work in progress), July
2004.
[I-D.ietf-sipping-ua-prof-framewk-reqs]
Petrie, D. and C. Jennings, "Requirements for SIP User
Agent Profile Delivery Framework",
draft-ietf-sipping-ua-prof-framewk-reqs-00 (work in
progress), March 2003.
[I-D.petrie-sipping-profile-datasets]
Petrie, D., "A Schema for Session Initiation Protocol User
Agent Profile Data Sets",
draft-petrie-sipping-profile-datasets-00 (work in
progress), July 2004.
[I-D.sinnreich-sipdev-req]
Butcher, I., Lass, S., Petrie, D., Sinnreich, H. and C.
Stredicke, "SIP Telephony Device Requirements and
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Configuration", draft-sinnreich-sipdev-req-04 (work in
progress), July 2004.
[RFC0822] Crocker, D., "Standard for the format of ARPA Internet
text messages", STD 11, RFC 822, August 1982.
[RFC0959] Postel, J. and J. Reynolds, "File Transfer Protocol", STD
9, RFC 959, October 1985.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol", RFC
2131, March 1997.
[RFC2132] Alexander, S. and R. Droms, "DHCP Options and BOOTP Vendor
Extensions", RFC 2132, March 1997.
[RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
[RFC2246] Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
RFC 2246, January 1999.
[RFC2396] Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
Resource Identifiers (URI): Generic Syntax", RFC 2396,
August 1998.
[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.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A. and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
[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.
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[RFC3361] Schulzrinne, H., "Dynamic Host Configuration Protocol
(DHCP-for-IPv4) Option for Session Initiation Protocol
(SIP) Servers", RFC 3361, August 2002.
[RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access
Protocol (v3): Technical Specification", RFC 3377,
September 2002.
[W3C.REC-xml-names11-20040204]
Tobin, R., Hollander, D., Layman, A. and T. Bray,
"Namespaces in XML 1.1", W3C REC REC-xml-names11-20040204,
February 2004.
Author's Address
Daniel Petrie
Pingtel Corp.
400 W. Cummings Park
Suite 2200
Woburn, MA 01801
US
Phone: "Dan Petrie (+1 781 938 5306)"<sip:dpetrie AT pingtel.com>
EMail: dpetrie AT pingtel.com
URI: http://www.pingtel.com/
Appendix A. Acknowledgments
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Acknowledgment
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Petrie Expires April 24, 2005 [Page 34]
