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Versions: (draft-petrie-sipping-config-framework) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 RFC 6080

SIPPING                                                        D. Petrie
Internet-Draft                                                SIPez LLC.
Expires: January 18, 2006                                  July 17, 2005


A Framework for Session Initiation Protocol User Agent Profile Delivery
               draft-ietf-sipping-config-framework-07.txt

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on January 18, 2006.

Copyright Notice

   Copyright (C) The Internet Society (2005).

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.   Introduction . . . . . . . . . . . . . . . . . . . . . . . .   4
   2.   Requirements Terminology . . . . . . . . . . . . . . . . . .   4
   3.   Profile Delivery Framework Terminology . . . . . . . . . . .   4
   4.   Overview . . . . . . . . . . . . . . . . . . . . . . . . . .   5
   5.   Use Cases  . . . . . . . . . . . . . . . . . . . . . . . . .   7
     5.1  Service Provider Use Case Scenario Bootstrapping with
          Digest Authentication  . . . . . . . . . . . . . . . . . .   7
     5.2  Service Provider Use Case Scenario Bootstrapping with
          Device Certificate . . . . . . . . . . . . . . . . . . . .   9
   6.   Data Model . . . . . . . . . . . . . . . . . . . . . . . . .   9
   7.   Profile Change Event Notification Package  . . . . . . . . .  11
     7.1  Event Package Name . . . . . . . . . . . . . . . . . . . .  11
     7.2  Event Package Parameters . . . . . . . . . . . . . . . . .  11
     7.3  SUBSCRIBE Bodies . . . . . . . . . . . . . . . . . . . . .  16
     7.4  Subscription Duration  . . . . . . . . . . . . . . . . . .  16
     7.5  NOTIFY Bodies  . . . . . . . . . . . . . . . . . . . . . .  17
     7.6  Notifier processing of SUBSCRIBE requests  . . . . . . . .  17
     7.7  Notifier generation of NOTIFY requests . . . . . . . . . .  19
     7.8  Subscriber processing of NOTIFY requests . . . . . . . . .  19
     7.9  Handling of forked requests  . . . . . . . . . . . . . . .  20
     7.10   Rate of notifications  . . . . . . . . . . . . . . . . .  20
     7.11   State Agents . . . . . . . . . . . . . . . . . . . . . .  20
     7.12   Examples . . . . . . . . . . . . . . . . . . . . . . . .  20
     7.13   Use of URIs to Retrieve State  . . . . . . . . . . . . .  21
       7.13.1   Device URIs  . . . . . . . . . . . . . . . . . . . .  22
       7.13.2   User and Application URIs  . . . . . . . . . . . . .  23
       7.13.3   Local Network URIs . . . . . . . . . . . . . . . . .  24
   8.   Profile Delivery Framework Details . . . . . . . . . . . . .  24
     8.1  Discovery of Subscription URI  . . . . . . . . . . . . . .  24
       8.1.1  Discovery of Local Network URI . . . . . . . . . . . .  25
       8.1.2  Discovery of Device URI  . . . . . . . . . . . . . . .  25
       8.1.3  Discovery of User and Application URI  . . . . . . . .  28
     8.2  Enrollment with Profile Server . . . . . . . . . . . . . .  29
     8.3  Notification of Profile Changes  . . . . . . . . . . . . .  29
     8.4  Retrieval of Profile Data  . . . . . . . . . . . . . . . .  29
     8.5  Upload of Profile Changes  . . . . . . . . . . . . . . . .  30
     8.6  Usage of XCAP with the Profile Package . . . . . . . . . .  30
   9.   IANA Considerations  . . . . . . . . . . . . . . . . . . . .  33
     9.1  SIP Event Package  . . . . . . . . . . . . . . . . . . . .  33
   10.  Security Considerations  . . . . . . . . . . . . . . . . . .  33
     10.1   Confidential Profile Content in NOTIFY Request . . . . .  34
     10.2   Confidential Profile Content via Content Indirection . .  34
     10.3   Integrity protection for non-confidential profiles . . .  36



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   11.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . .  36
   12.  Change History . . . . . . . . . . . . . . . . . . . . . . .  36
     12.1   Changes from
            draft-ietf-sipping-config-framework-06.txt . . . . . . .  36
     12.2   Changes from
            draft-ietf-sipping-config-framework-05.txt . . . . . . .  37
     12.3   Changes from
            draft-ietf-sipping-config-framework-04.txt . . . . . . .  37
     12.4   Changes from
            draft-ietf-sipping-config-framework-03.txt . . . . . . .  38
     12.5   Changes from
            draft-ietf-sipping-config-framework-02.txt . . . . . . .  38
     12.6   Changes from
            draft-ietf-sipping-config-framework-01.txt . . . . . . .  38
     12.7   Changes from
            draft-ietf-sipping-config-framework-00.txt . . . . . . .  38
     12.8   Changes from
            draft-petrie-sipping-config-framework-00.txt . . . . . .  39
     12.9   Changes from draft-petrie-sip-config-framework-01.txt  .  39
     12.10  Changes from draft-petrie-sip-config-framework-00.txt  .  39
   13.  References . . . . . . . . . . . . . . . . . . . . . . . . .  40
     13.1   Normative References . . . . . . . . . . . . . . . . . .  40
     13.2   Informative References . . . . . . . . . . . . . . . . .  41
        Author's Address . . . . . . . . . . . . . . . . . . . . . .  42
        Intellectual Property and Copyright Statements . . . . . . .  43


























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1.  Introduction

   Today all SIP (Session Initiation Protocol) [RFC3261] 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 (User Agent)
   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.  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].

3.  Profile Delivery Framework Terminology





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   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 agents.
   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 URIs (Uniform Resource Identifiers) 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).
   hotelling- when a user moves to a new user agent (i.e. that is not
      already provisioned to know the user's identity, credentials or
      profile data) and gives the user agent sufficient information to
      retrieve the user's profile(s).  The user agent either permanently
      or temporarily makes the user's profiles effective on that user
      agent.
   roaming- when the user agent moves to a different local network

4.  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.  The
   means of discovery is described in Section 8.1.

   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



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   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).  Enrollment which is performed by the
   device by constructing and sending a SUBSCRIBE request to profile
   delivery server for the event package described in Section 7.

   Profile Retrieval is the process of retrieving the content for each
   of the profiles the UA requested.  The profiles are retrieved either
   directly or indirectly from the NOTIFY request body as describe in
   Section 7.5 and Section 8.4.

   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 notification is provided by
   the NOTIFY request for the event package as described in Section 7.8
   and Section 8.3.

   Profile Change Upload is the process by which a UA or other entity
   (e.g. corporate directory or configuration management server) pushes
   a change to the profile data back up to the profile delivery server.
   This process is described in Section 8.5.

   This framework defines a new SIP event package [RFC3265] to solve
   enrollment and profile change notification steps.  The event package
   in Section 7 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 agents 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
   (see Section 8.1).  SIP is only needed for the enrollment (see
   Section 8.2) and change notification functionality (see Section 8.3)
   of the profile delivery framework.  In many SIP environments (e.g.
   carrier/subscriber and multi-site enterprise) firewall, NAT (Network



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   Address Translation) 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.  The local network profile (see Section 6, Section 7.13.3
   and Section 8.1.1) provides the means to get firewall and NAT
   traversal mechanism information to the device.  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.

   The content delivery server may be either in the public network or
   accessible through a private network.  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.).

5.  Use Cases

   The following use case are intented to help give a understanding of
   how the profile delivery framework can be used.  These use cases are
   not intended to be exhaustive in demonstrating all the capabilities
   or ways the framework can be applied.

5.1  Service Provider Use Case Scenario Bootstrapping with Digest
     Authentication

   The following describes a use case scenario for bootstrapping a new
   user agent, which has had no prior provisioned information, to the
   point of being functional with a SIP Service Provider's system.  In
   this example scenario, the user has purchased a new SIP user agent.
   The user signs up for the service to obtain three pieces of
   information: a hostname, a user ID and a password.  These three
   pieces of information may be one-time use, that become invalid after
   the one use.  This scenario assumes that no association or mapping
   between the device and the user's account is created before the
   following steps:




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   1.  The user plugs the device in to provide power and network
       connectivity the first time (or installs the software in the case
       of a software user agent).  The device subscribes to the local
       network to get the local network profile.  However as the device
       is plugged into a residential LAN or router, there is no profile
       delivery server for the local network profile (see Section 8.1.1
       and Section 7.13.3).  The device assumes symmetric SIP signalling
       as there is not local network profie which may have provided
       other firewall or NAT traversal mechanism information.
   2.  The device prompts the user for the hostname to subscribe to for
       the device profile.  The hostname was provided by the service
       provider and use as the host part of the SUBSCRIBE profile URI
       described in Section 7.13.1.  Note: in a scenario where the
       system operator (e.g. enterprise) has control of the network, the
       hostname for the SUBSCRIBE can be discovered (see Section 8.1.2)
       to avoid the need for the user to enter the hostname.
   3.  The device creates a TLS connection for the SIP SUBSCRIBE request
       to the provided hostname.  The device verifies the server's
       certificate.  If the common name does not match the hostname or
       the certificate is not valid, the device warns the user and
       prompts whether to continue.
   4.  The profile delivery server receives the SUBSCRIBE request for
       the device profile and sends a NOTIFY with content indirection
       containing the HTTPS URI for the device profile (see
       Section 7.5).
   5.  The device receives the NOTIFY request with the device profile
       URI.  The device prompts the user for the user ID and password
       provided by the service provider.  The device does an HTTPS GET
       to retrieve the device profile (see Section 8.4 and Section 7.8).
       The profile delivery server challenges for Digest authentication.
       The device re-sends the HTTPS GET with Digest credentials using
       the user ID and password entered by the user.  Note: for devices
       with only DTMF style input, the service provider may provide the
       host, user ID and password in octal format that can be entered
       requiring only digits.
   6.  The profile delivery server receives the HTTP GET request for the
       device profile along with the user ID and password for the
       specific user.  At this point the profile delivery server has
       authenticated the user and can create an association between a
       specific device identified in the HTTPS URI and the user or user
       account (see Section 10.2).  The profile delivery server provides
       the device profile which contains the on-going SUBSCRIBE request
       URIs for the device, user and application profiles along with
       credentials for retrieving the profiles.
   7.  The device receives the device profile from the HTTPS response,
       re-SUBSCRIBEs using the device profile URI provided in the
       profile.  The device profile also may contain URIs for the
       default user's user and application profile SUBSCRIBE request



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       URIs for the SIP event package defined in Section 7.  The device
       uses these URIs to retrieve user and application profiles in a
       similar way to the device profile.  After retriving these
       profiles the device is fully functional in the service provider's
       SIP service.

5.2  Service Provider Use Case Scenario Bootstrapping with Device
     Certificate

   The following describes another use case scenario where the device
   implementor provides a certificate for the device which authenticates
   the device ID.  In this scenario, the user signs up for the SIP
   service with the service provider and provides the device ID (see
   Section 7.13.1 for more information on device ID) to the service
   provider prior to the following steps, so that the service provider
   has an association or mapping between the device ID and the user
   account ahead of time.  The service provide gives the user a hostname
   to be entered on the device.

   1.  Step 1-3 occur the same as in the prior use case described in
       Section 5.1.
   2.  The device receives the NOTIFY request with the device profile
       URI.  The device does an HTTPS GET to retrieve the device profile
       (see Section 8.4 and Section 7.8).
   3.  The profile delivery server requests the device certficate in the
       TLS connection used for the HTTPS GET.  The device has a
       certificate which has a SIP URI in the Subject Alternative Name
       field that contains the device ID.  The device certificate is
       signed and provided by the implementor for the purpose of
       authenticating the device ID in the initial bootstrapping process
       only.  The profile delivery server validates the device ID and
       encrypts the device profile using the public key in the device's
       certificate as described in Section 10.2
   4.  The device receives the encrypted device profile from the HTTPS
       response, decrypts the profile using it private key.  The process
       continues in a similar way to step 6 in the above use case.  The
       device profile contains a more perminent device certificate and
       private key or Digest authentication credentials which is used
       for on-going device ID authentication.

6.  Data Model

   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 (described above) 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



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   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 roaming (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 (Application Service Provider).  The local
   network profile may delivered by a WLAN (Wireless LAN) 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 bootstrapping 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 bootstrapping scenario, a device straight out of
   the box (software or hardware) does not know anything about its 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 local network profile is subscribed to and retrieved based upon a
   URI formed from the local network domain.  The local network profile
   is subscribed to first as it may contain information on how to
   communicate to the Internet or primary network from the local network
   (e.g.  HTTP proxy, SIP firewall or NAT traversal information).  The
   device instance id is used to form the user id part of the URI for
   subscribing to the device and local network profiles.  The device
   profile may contain a default user AOR (Address of Record) for that
   device.  The default user AOR may then be 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.






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7.  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 profiles 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.

7.1  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].

7.2  Event Package Parameters

   This package defines the following new parameters for the event
   header: "profile-type", "vendor", "model", "version", "effective-by",
   "document", "auid", "network-user".  The "effective-by" parameter is
   for use in NOTIFY requests only.  The "effective-by" parameter is
   ignored if it appears in a SUBSCRIBE request.  The other parameters
   are for use in the SUBSCRIBE request and are ignored if they appear
   in NOTIFY requests.




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   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 defined here are "device", "user",
   "application" and "local-network".  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.
   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-network" type profile
   indicates the desire for profile 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.  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 ABNF,
   EQUAL and token are defined in [RFC3261].

   Profile-type   = "profile-type" EQUAL profile-value
   profile-value  = profile-types / token
   profile-types  = "device" / "user" / "application" / "local-network"

      The "device", "user", "application" or "local-network" 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.

   The rational for the separation of user, device, application and
   local network type profiles is provided in Section 4.  It should be



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   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, if defined
   in the device profile, 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 for merging the
   constraints across the multiple profile types can only unambiguously
   be defined in the context of the profile syntax and semantics.  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.  The
   implementer SHOULD use their DNS domain name (e.g. example.com) as
   the value of the "vendor" parameter so that it is known to be unique.
   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.  In the
   following ABNF, EQUAL and quoted-string are defined in [RFC3261].

   Vendor       =  "vendor" EQUAL quoted-string
   Model        =  "model" EQUAL quoted-string
   Version      =  "version" EQUAL quoted-string

   The "network-user" parameter SHOULD be set when subscribing for
   device and local network profiles if the user's AOR is known.  When
   the profile-type is "device" or "local-network", 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
   SHOULD authenticate the subscriber to verify the AOR in the "network-
   user" parameter if the profile provided is specific to the AOR.  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, name-addr, addr-spec are defined in [RFC3261].

   Network-User =  "network-user" EQUAL name-addr / addr-spec



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   When the profile-type is "device", the user agent SHOULD set the
   "network-user" parameter to the user's AOR if it is known.  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 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 permanent.

   In the case where the profile-type is "local-network", the user agent
   SHOULD set the "network-user" parameter if the user's AOR is known.
   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.  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 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.  In the following ABNF,
   EQUAL and DIGIT are defined in [RFC3261].

   Effective-By =  "effective-by" EQUAL 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
   for which it wishes to receive change notification.  This is 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.  This provides a filtering mechanism to restrict the
   content to be retrieved and for which change notification is to be
   received.  (The size of the content is important in limited bandwidth
   environments.)  The "document" parameter value syntax is a quoted
   string.  The values for the "document" parameter are defined as part
   of the profile data format, which is out of scope for this document.
   To use the "document" parameter, the profile data format, must also
   define a URL path schema.  For more details on the use of this
   package and the "document" parameter with XCAP see Section 8.6.  The
   "document" parameter MAY be set in SUBSCRIBE requests for any of the
   profile types.  It is ignored in all other messages.  In the
   following ABNF EQUAL and quoted-string is defined in [RFC3261].



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   Document     =  "document" EQUAL quoted-string

   The "auid" parameter MAY be set when the "profile-type" parameter
   value is "application".  The "auid" 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 "auid" parameter.  Like the "document"
   parameter, the "auid" parameter provides a filtering mechanism on the
   profile content.  The "auid" parameter value is a quoted string.  The
   values for the "auid" parameter are defined as part of the profile
   data format to be used with XCAP (see [I-D.ietf-simple-xcap] ), which
   is out of scope for this document.  The "auid" parameter has meaning
   only in SUBSCRIBE requests when the "profile-type" Event header
   parameter is set to "application".  It is an error to set both the
   "document" and "auid" parameters in a SUBSCRIBE request.  The "auid"
   parameter is ignored in all other messages.

   AUID       =  "auid" EQUAL quoted-string


   SUBSCRIBE request Event header examples:
   Event: ua-profile;profile-type=device;
               vendor="vendor.example.com";model="Z100";version="1.2.3"

   Event: ua-profile;profile-type="user";
      document="user-aor/";
      vendor="premier";model="trs8000";version="5.5"

   NOTIFY request Event header examples:
   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 four profile types:















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   profile-type || device | user | application | local-network
   ===========================================================
   vendor       ||   m    |  m   |      m      |        m
   model        ||   m    |  m   |      m      |        m
   version      ||   m    |  m   |      m      |        m
   network-user ||        |      |             |        s
   document     ||   o    |  o   |      o      |        o
   auid         ||        |      |      o      |
   effective-by ||        |      |             |

   m - manditory
   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 four profile types:

   profile-type || device | user | application | local-network
   ===========================================================
   vendor       ||        |      |             |
   model        ||        |      |             |
   version      ||        |      |             |
   network-user ||        |      |             |        s
   document     ||   o/m  |  o/m |     o/m     |       o/m
   auid         ||        |      |     o/m     |
   effective-by ||   o    |  o   |      o      |        o

   o/m - manditory if provided in the SUBSCRIBE request


7.3  SUBSCRIBE Bodies

   This package defines no new use of the SUBSCRIBE request body.
   Future 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.

7.4  Subscription Duration

   As the presence (or lack of) a device or user agent is not very time
   critical to the functionality of the profile delivery server, it is
   recommended that default subscription duration be 86400 seconds (one
   day).  A one-time fetch of a profile can be accomplished by setting
   the Expires parameter to 0 as defined in [RFC3265] resulting in a
   single NOTIFY with no change notification.




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7.5  NOTIFY Bodies

   The size of profile content is likely to be hundreds to several
   thousand of bytes in size.  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 MIME header described 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
   Content-Type MUST be specified for each URI.  For minimal
   interoperability, the profile delivery server MUST support the
   "http:" and "https:" URI schemes for content indirection.  Other URI
   schemes MAY also be provided in the content indirection.  However the
   security considerations are define for content indirection using HTTP
   and HTTPS.  Other protocols MAY be supported for content indirection,
   but are out of scope of this document.

      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.

   The URI scheme [RFC2396] used in content indirection may be dictated
   by the profile content that is required.  It is expected that FTP
   [RFC0959], HTTP [RFC2616], HTTPS [RFC2818], LDAP [RFC3377], XCAP
   [I-D.ietf-simple-xcap] and other URI schemes could be used by this
   package and framework if the subscribing user agent and profile
   delivery server both support the same scheme.  The negotiation of the
   URI scheme is described in the following sections.

7.6  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



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   techniques in Section 10.  If content indirection is not used, the
   subscribe server SHOULD reject SUBSCRIBE requests from conections
   that are not over TLS and SHOULD challenge the SUBSCRIBE request with
   SIP Digest authentication.  The subscriber MUST support the "http:"
   or "https:" URI scheme for content indirection.  If the subscriber
   wishes to use a URI scheme other than "http:", the subscriber must
   use the "schemes" Contact header field parameter to indicate the URI
   scheme as defined in [I-D.ietf-sip-content-indirect-mech].  For
   example the subscriber may request that content indirection use the
   "ldaps:" URI scheme by including "ldaps" in the "scheme" Contact
   header parameter of the SUBSCRIBE request.  If the subscriber does
   not specify the URI scheme, the notifier may use either "http:" or
   "https:".

      The profile generation 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
   for unprovisioned users or devices as an administrator may add the
   user or device to the system after the initial subscription, 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 re-subscribe.  This may be difficult if the user
   agent and administrator are at different locations.

   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.

   When the Event header "profile-type" is "device" and the user agent
   has provided the user's AOR in the "network-user" parameter, the



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   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 SUBSCRIBE request before
   changing the default user associated with the device.

7.7  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. for a user agent with telephony capabilities, 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 SUBSCRIBE request is a known identity and is
   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 indirection mime type was included in the Accept
   header) containing the URI for the profile.  To protect the integrety
   of the profile data or indirect content profile data URIs, the
   notifier SHOULD send the NOTIFY request on the same TLS connection as
   the SUBSCRIBE request came in on if TLS was used.

   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.

7.8  Subscriber processing of NOTIFY requests

   The user agent subscribing to this event package MUST adhere to the
   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 7.7).  By default the user agent
   makes the profiles effective as soon as it thinks that it is non-
   obtrusive to do so (e.g. when there are no active calls).  Profile
   changes SHOULD affect behavior on all new dialogs which are created
   after the notification, but may not be able to affect existing



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   dialogs.  The user agent SHOULD use one of the techniques specified
   in Section 10 to securely retrieve the profiles.  If the subscriber
   included the MIME type message/external-body for content indirection
   in the SUBSCRIBE request Accept header, the subscriber MUST support
   the http: or https: URI schemes for content indirection.  If the
   subscriber indicated alternative URI schemes for content indirection
   it MUST also indicate support for http: or https:.  The subscriber
   should still be prepared to use http: or https: as the profile
   delivery server may not support the alternative URI schemes.

7.9  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].

7.10  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.

7.11  State Agents

   State agents are not applicable to this event package.

7.12  Examples

   Example SUBSCRIBE and NOTIFY request using content indirection:





















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   SUBSCRIBE sip:MAC%3aFF00000036C5@acme.example.com SIP/2.0
   Event: ua-profile;profile-type=device;vendor="vendor.example.com";
                            model="Z100";version="1.2.3"
   From: sip:MAC%3aFF00000036C5@acme.example.com;tag=1234
   To: sip:MAC%3aFF00000036C5@acme.example.com;tag=abcd
   Call-ID: 3573853342923422@10.1.1.44
   CSeq: 2131 SUBSCRIBE
   Contact: sip:MAC%3aFF00000036C5@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:MAC%3aFF00000036C5@10.1.1.44 SIP/2.0
   Event: ua-profile;effective-by=3600
   From: sip:MAC%3aFF00000036C5@acme.example.com;tag=abcd
   To: sip:MAC%3aFF00000036C5@acme.example.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--


7.13  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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7.13.1  Device URIs

   The URI for the "device" type profile (device URI) is based upon the
   identity of the device.  The device URI MUST be unique across 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 changed its device URI, the profile delivery
      server would not know the 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 of the profile delivery
      server.  The subscribing device has no way of knowing whether the
      profiles for each device are different.  For this reason the
      device must always use a unique id in the device SUBSCRIBE request
      URI.  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 8.1.3.

   The URI for the device type profile MUST 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 delivery server
   which manages that user agent.  A means of discovering the host and
   port portion is discussed in Section 8.1.  There is an 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.  The MAC address or UUID SHOULD be used for
   constructing a unique identifier to be used in the user portion of
   the device URI.

   If the identifier is a MAC address, it MUST be formatted as the
   letters "MAC:" followed by a 12 digit hexadecimal representation of
   the MAC address.  The address can not include ":", whitespace, or
   other formatting.
      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 dedicated telephone appliance).  The MAC address may not be used
      if more than one user agent instance exists using 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



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      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 upper case
      with no punctuation for consistency across implementations.  A
      prefix of "MAC:" should be added to the MAC address to form a
      proper URN [RFC2141].  For example a device managed by
      sipuaconfig.example.com using its MAC address to form the device
      URI might look like:
      sip:MAC%3a00DF1E004CD0@sipuaconfig.example.com.


          UHEX  =  DIGIT / %x41-46 ;uppercase A-F
          MAC  =  %x4d.41.43 ; MAC in caps
          mac-ident = MAC ":" 12UHEX

   When the MAC address is not used in the device URI, UUID SHOULD be
   used.

      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 UUID is used as the user portion
      of the device URI.  The same approach to defining a user agent
      instance ID as [I-D.ietf-sip-gruu] should be used.  When
      constructing the instance id the implementer should also consider
      that a human may need to manually enter the instance id to
      provision the device in the profile delivery server (e.g. 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-7ced-11d0-a765-00a0c91e6bf6 would be escaped to
      look as follows in a URI:
      sip:urn%3auuid%3af81d4fae-7ced-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.

7.13.2  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



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   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.

7.13.3  Local Network URIs

   The URI for the "local-network" type profile is based upon the
   identity of the local network.  When subscribing to the local network
   profile, the user part of the URI SHOULD be the same device ID used
   as the user part of the device profile SUBSCRIBE request URI defined
   in Section 7.13.1.  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 8.1.  The user agent 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.  When "network-user" is provided the
   profile delivery server SHOULD authenticate the user before providing
   the profile if additional privileges are granted.  Example URI:
   sip:MAC%3a00DF1E004CD0@example.com

      The local network profile SUBSCRIBE request URI 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 request URI.  Even
      though every device may get the same or similar local network
      profiles, the uniqueness of the URI provides an important
      capability.  Having unique URIs 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.

8.  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.

8.1  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
   bootstrapping situation as the 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



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   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.

8.1.1  Discovery of Local Network URI

   The "discovered" host for the "local-network" 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 remembered if the user agent moves from one local
   network to another other.  The user agent should perform the local
   network discovery to construct the network profile subscription
   request URI every time it starts up or network connectivity is
   regained.

      For example: The user agent requested and received the local
      domain name via DHCP: airport.example.net.  If the device ID is:
      MAC:00DF1E004CD0, the local network profile SUBSCRIBE request URI
      would look like: sip:MAC%3a00DF1E004CD0@airport.example.net.  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
      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"


8.1.2  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 7.13.1 describes how to form the user part of the device
   profile SUBSCRIBE request URI used 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



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   variation of environments in which the enrolling user agent may
   reside (e.g. behind residential router, enterprise LAN, WLAN 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 request URI, as described in Section 7.13.1,
       is to use the host and port of the outbound 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 ua-profile event, the next discovery mechanism
       should be tried.

          For example: Consider a dedicated hardware device with a
          single user agent having the MAC address: abc123efd456.  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:MAC%3aABC123EFD456@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 ua-
       profile event, the next discovery mechanism should be tried.




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          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:MAC%3aABC123EFD456@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 by concatenating
       "sipuaconfig" and 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 ua-
       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:MAC%3aABC123EFD456@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, a manual means for the
       user to enter the host and port used to construct the SUBSCRIBE
       request URI MUST be provided by the user agent.

   Two approaches to the manual discovery process are suggested.  In the
   first approach using SIP, the user agent provides a means for
   entering the subscription host and port information for the request
   URI along with the user id and password to be used for authentication
   of the SUBSCRIBE request.  With this approach the user agent begins
   with the enrollment process followed by the change notification and
   profile retrieve steps.

   An alternative to the manual discovery using SIP, is to start with
   the retrieve process.  The user agent provides a means of entering a
   HTTPS URI along with the user id and password to be used for
   authentication of the retrieval of the profile.  The retrieved device
   profile may contain the properties for the SUBSCRIBE request URI and
   credentials to enroll and get change notification of profile changes.
   This approach bootstraps the process in a different step in the
   cycle, but uses the same profile framework.  When the device starts
   with retrieval of the profile via HTTPS (instead of a SIP SUBSCRIBE
   to the event package), the device MUST provide the Event header in
   the HTTPS request using the same format as described for the



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   SUBSCRIBE request (see Section 7.2) .  The Event header is necessary
   to determine which profile is requested as well as for providing
   specific information about the device.

   Once a user agent has successfully discovered, enrolled and received
   a NOTIFY response with profile data or URI(s), the user agent should
   cache (i.e. store persistantly) the device profile SUBSCRIBE request
   URI (rather than reconstructing it as described in the discovery
   process every time the device is restarted) 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 7.6) with no profile data or 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.

8.1.3  Discovery of User and Application URI

   The user's AOR may be preprovisioned or provided via SIM or flash
   key, etc.  The device profile may define a default user and AOR.  If
   provided in the device profile and a preprovisioned user AOR is not
   provided, the default user's AOR is used to subscribe to the "user"
   and "application" profiles.  If not provided through the above two
   approaches, the AOR to be used for the "user" and "application"
   subscription URI, is "discovered" manually by prompting the user.
   The URI obtained in the discovery steps described above for the
   "user" and "application" profile subscriptions is stored persistantly
   in the device until explicitly reset or updated by the user or
   profile.





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8.2  Enrollment with Profile Server

   Enrollment is accomplished by subscribing to the event package
   described in Section 7.  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
   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 7.5.

8.3  Notification of Profile Changes

   The NOTIFY request in the ua-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 notification
   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.

8.4  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 7.5.
   The profile delivery server SHOULD secure the content of the profiles
   using one of the techniques described in Section 10.  The user agent
   SHOULD make the new profiles effective in the timeframe described in
   Section 7.2.

   The contents of the profiles SHOULD be cached (i.e. stored
   persistently) by the user agent.  The cache should be used if the
   user agent is unable to successfully SUBSCRIBE or receive the NOTIFY
   providing the most recent profile.  The cached profile should be
   replaced each time a profile is received in a NOTIFY or retrieved via
   content indirection.  This it to avoid the situation where the
   content delivery server being not available, leaves the user agent
   non-functional.  The user agent should verify that it has the latest
   profile content using the "hash" parameter defined in [I-D.ietf-sip-
   content-indirect-mech].




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8.5  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].

8.6  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
   model presented here.

   When a user or device enrolls with a SUBSCRIBE request, the request
   URI will contain 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
   "auid" Event header parameters specify the specific XCAP application
   usage.

   In particular, when the Event header parameter "profile-type" is
   "application", the "auid" MAY be included to contain the XCAP
   Application Unique ID (AUID) [I-D.ietf-simple-xcap].  When the
   "profile-type" is "application", but the "auid" 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-network",
   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.  The "auid" SHOULD NOT
   be present if the "document" is also present.  The "document"



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   attribute specifies a relative path reference.  The path is
   constucted from a set of path segments (e.g. directories) using the
   "/" separator.  For XCAP the relative document path is constructed
   using the following steps:"

   1.  Its first path segment is either "global", specifying global
       data, or "user", specifying user data for the user in the request
       URI.
   2.  If the prior path segment is "user", the next path segment
       identifies the the user's home directory.  That is the next path
       segment is the user's directory name.  The user's directory name
       is appended onto the "document" path with the "/" separator.  If
       the prior path segment is "global" nothing is appended to the
       document path for this step.
   3.  When the "profile-type" is "application", the next path segment
       to append (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.
   4.  If the AUID was added to the document path in the prior step,
       additional path segments may be added according to the specific
       schema of the profile and the query mechanism provided in
       [I-D.ietf-simple-xcap].

   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 contains the following
   Request-Line and Event header:  (Note that line folding of the
   Request-URI is illegal in SIP.  The Request URI is shown broken
   across the first 3-lines here only due to formatting limitations of
   IETF documents.  The Event header is shown continued across a second
   line for the same reason.)


   SUBSCRIBE
    sip:urn%3auuid%3a00000000-0000-0000-0000-0003968cf920@example.com
    SIP/2.0
   Event: ua-profile;profile-type=device;Vendor="vendor2";
    Model="1";Version="2.2.2"

   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.  The user ID that might be used in the case of
   a device profile could be the device ID which is identified in the
   user part of the SUBSCRIBE URI.  The XCAP server may use a root
   directory of: http://xcap.example.com/root.  Local policy may provide
   a mapping for the AUID "vendor2-device-data" based upon the "vendor"
   parameter and a document called "index" within the user directory,



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   the corresponding HTTP URI for the document might be: (Note that this
   URL is only one line; it is split across three lines due to
   formatting limitations of IETF documents.)


   http://xcap.example.com/root/users/
    urn%3auuid%3a00000000-0000-0000-0000-0003968cf920/
    vendor2-device-data/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:alice@example.com SIP/2.0
   Event: ua-profile;profile-type=application;Vendor="vendor2";
    Model="1";Version="2.2.2"

   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/users/user-aor/rls-services
   http://xcap.example.com/root/users/user-aor/resource-lists

   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: ua-profile;profile-type=application;auid="resource-lists";
    Vendor="vendor2";Model="1";Version="2.2.2"

   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



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   which can indicate what document has changed.  This includes content
   indirection, but also the xcap diff format [I-D.ietf-simple-xcap-
   package].

9.  IANA Considerations

   There are several IANA considerations associated with this
   specification.

9.1  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).
      Person to Contact: Daniel Petrie dan.ietf AT SIPez DOT com
      New event header parameters: profile-type, vendor, model, version,
      effective-by, document, auid, network-user

10.  Security Considerations

   Profiles may contain sensitive data such as user credentials and
   personal information.  The protection of this data depends upon how
   the data is delivered.  Some profiles may be safe to deliver without
   the need to protect the content.  For example in some environments
   the local network profile may contain the list of codecs that are
   acceptable for use in the network and information on NAT traversal
   such as a STUN server to use.  As the information in this example
   local network profile does not contain passwords or sensitive
   information it may be acceptable to provide it without authentication
   or confidentiality (encryption).  We refer to these as non-
   confidential profiles.  Non-confidential profiles require message
   integrity and profile server authentication, as described in
   Section 10.3.  However any profiles that contain personal
   information, passwords or credentials (confidential profiles) require
   mutual authentication, confidentiality, and message integrity, and
   must follow the guidance provided in the next two subsections.
   Profile specifications that define schemas MUST identify if they
   contain confidential data to indicate which of the security
   approaches describer here should be used.

   The profile data is delivered in either the NOTIFY request or via the
   URI scheme indicated in the content indirection in the NOTIFY
   request.  The security approach is different for these two delivery
   mechanisms.



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   Subscribers implementing this specification MUST implement either
   HTTP or HTTPS.  Subscribers also MUST implement the hash verification
   scheme described in SIP content indirection [I-D.ietf-sip-content-
   indirect-mech].  SIP profile delivery servers MUST implement both
   HTTP and HTTPS, and SHOULD implement a SIP Authentication Service as
   described in the SIP Identity mechanism [I-D.ietf-sip-identity].  All
   SIP entities are already required to implement SIP Digest
   authentication [RFC3261].

10.1  Confidential Profile Content in NOTIFY Request

   When the profile data is delivered directly in the NOTIFY request,
   the SUBSCRIBE request MUST be authenticated using the SIP Digest
   authentication mechanism.  As the profile content is delivered in the
   resulting NOTIFY request to the subscription, authenticating the
   SUBSCRIBE is the only way to prevent unauthorized access to the
   profile data.  To provide message integrity and confidentiality over
   the profile data, a direct TLS connection MUST be established for the
   SUBSCRIBE request.  The device SHOULD authenticate the server via the
   TLS connection, which also provides a means of verifying that a
   direct TLS connection was used (e.g.  The device may prompt the user
   to verify the Common Name in the server's certificate.).  The server
   may challenge the device for its certificate, when establishing the
   TLS connection, to obtain the public to S/MIME encode the NOTIFY
   request body containing the profile data.  Because the device
   verified that it has a direct TLS connection by verifying the
   server's certificate and the server verified the identity of the
   device using Digest Authentication, the server can assume the
   certficate provided by the device is authenticated.  The use of
   S/MIME in the NOTIFY request does not relieve the need to
   authenticate the SUBSCRIBE request using SIP Digest authentication.
   In this scenario S/MIME only provides message integrity and
   confidentiality of the content of the profile.  If S/MIME is not used
   for the profile data in the NOTIFY request, the notifier MUST use the
   same direct TLS connection established by device for the SUBSCRIBE
   request.  In this scenario the use of user specific ID and secret in
   the Digest Authentication can be used to establish an association
   between user ID and the device ID provide in the device profile
   SUBSCRIBE request.

10.2  Confidential Profile Content via Content Indirection

   When the profile data is delivered via content indirection,
   authentication, integrity, confidentiality are all provided in the
   profile indirection retrieval scheme.  When content indirection is
   used, the SUBSCRIBE request does not need to be authenticated.  There
   is a TLS certificate approach and a Digest Authentication approach
   which may be used to provide the required security.  The profile



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   delivery server MUST support both of these methods.  The device MUST
   support the Digest Authentication method to provide minimal
   interoperablity.

   For the TLS certificate approach, the device requests the profile
   using HTTPS.  To provide authentication, the server challenges the
   device for its certificate.  The server obtains the user part of the
   SIP URI in the Subject Alternative Name field of the device's
   certificate.  The user part of the SIP URI in the device's
   certificate is used as the device ID to authenticate if the device is
   authorized to retieive the specified profile.  The device
   certificates chain of authorities MUST also be verified.  This
   approach for providing security requires that the device ID and
   associated user are provisioned to the content indirection retreival.

   For the Digest Authentication approach, HTTPS SHOULD be used to
   provide confidentiality of the profile data.  HTTP Digest
   Authentication [RFC2617] MUST be used to authenticate and authorize
   the device to retrieve the profile.  The shared secret used in the
   Digest Authentication is provided through out of band means to the
   device or user of the device.  The same credentials used for SIP
   Digest authentication (e.g. authenication of SIP SUBSCRIBE and
   REGISTER requests) are used in the HTTPS request.  Other URI schemes
   may be used, but are not defined in this document.  A non-replayable
   authentication mechanism such as Digest authentication MUST be used
   for the content indirection URI scheme which provides the profile
   data (e.g.  LDAP, HTTP and HTTPS all support Digest authentication).
   URI schemes which provide no authentication or only clear-text
   authentication SHOULD NOT be used for profile delivery as they are
   vulnerable to replay attacks (e.g.  TFTP does not provide
   authentication).
      Without a suitable authentication mechanism, the content
      indirection profile delivery URI scheme is susceptible to replay
      attacks.  Even if the profile is symmetrically encrypted, if it
      can be retrieved through a replay attack, the encrypted profile
      can be used for offline attacks to crack the encryption key.

   The profile delivery scheme MUST use channel security such as TLS
   (e.g.  HTTPS) to protect the content from being snooped in transport
   to the user agent.  Mutual authentication using the client and server
   certificates MAY be used to verify the authenticity of the user or
   device identity and the profile delivery server identity.  The user
   agent SHOULD provide a mechanism for the user to approve the
   SUBSCRIBE server identity or provision the acceptable server identity
   through out of band means.






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10.3  Integrity protection for non-confidential profiles

   Even for non-confidential profiles, the subscriber MUST verify the
   authenticity of the profile delivery server, and MUST verify that the
   integrity of the profile data and content indirection URI, if one is
   provided.  To meet these requirements in the SIP messaging the NOTIFY
   request MUST use a SIP Identity header [I-D.ietf-sip-identity], or
   S/MIME.  If content is provided via redirection, the content
   indirection "hash" parameter MUST be included unless the profile data
   is delivered via a protocol which natively provides authentication
   and message integrity, such as HTTP or LDAP protected by TLS.  The
   content retrieved via the content indirection URI MUST be integrity
   checked using the "hash" parameter.

   For example, Alice subscribes to the local domain profile for
   paris.example.com.  She receives the following NOTIFY request which
   uses content indirection, including a "hash" parameter.  Alice uses
   the Identity header from the NOTIFY to verify that the request came
   from paris.example.com and that the body was not modified.  Then she
   fetches the content at the provided URI and verifies that the hash
   she calculates from the profile matches the hash provided in the SIP
   signaling.

11.  Acknowledgements

   Many thanks to those who contributed and commented on the many
   iterations of this document.  Detailed input was provided by Jonathan
   Rosenberg from Cisco, Henning Schulzrinne from Columbia University,
   Cullen Jennings from Cisco, Rohan Mahy from Airespace, 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.

12.  Change History

   [[RFC Editor:  Please remove this entire section upon publication as
   an RFC.]]

12.1  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 clarifcation 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



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      concepts and functionality is defined in the document.
      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!

12.2  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.

12.3  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.





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      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.

12.4  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-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.

12.5  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.

12.6  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.

12.7  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.



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   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 ua-profile

   Three high level security approaches are now specified.

12.8  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 Estacado Systems for the great comments and input.

12.9  Changes from draft-petrie-sip-config-framework-01.txt

   Changed the name as this belongs in the SIPPING work group.

   Minor edits

12.10  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



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   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.

13.  References

13.1  Normative References

   [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-identity]
              Peterson, J. and C. Jennings, "Enhancements for
              Authenticated Identity Management in the Session
              Initiation  Protocol (SIP)", draft-ietf-sip-identity-05
              (work in progress), May 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.

   [RFC2246]  Dierks, T. and C. Allen, "The TLS Protocol Version 1.0",
              RFC 2246, January 1999.

   [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.




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   [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.

13.2  Informative References

   [I-D.ietf-simple-xcap]
              Rosenberg, J., "The Extensible Markup Language (XML)
              Configuration Access Protocol (XCAP)",
              draft-ietf-simple-xcap-07 (work in progress), June 2005.

   [I-D.ietf-simple-xcap-list-usage]
              Rosenberg, J., "Extensible Markup Language (XML) Formats
              for Representing Resource Lists",
              draft-ietf-simple-xcap-list-usage-05 (work in progress),
              February 2005.

   [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-03 (work in progress),
              January 2005.

   [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-04 (work in progress),
              July 2005.

   [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.



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   [I-D.sinnreich-sipdev-req]
              Sinnreich, H., "SIP Telephony Device Requirements and
              Configuration", draft-sinnreich-sipdev-req-07 (work in
              progress), June 2005.

   [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.

   [RFC2131]  Droms, R., "Dynamic Host Configuration Protocol",
              RFC 2131, March 1997.

   [RFC2141]  Moats, R., "URN Syntax", RFC 2141, May 1997.

   [RFC2396]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifiers (URI): Generic Syntax", RFC 2396,
              August 1998.

   [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
   SIPez LLC.
   34 Robbins Rd
   Arlington, MA  02476
   US

   Phone: "+1 617 273 4000
   Email: dan.ietf AT SIPez DOT com
   URI:   http://www.SIPez.com/










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Acknowledgment

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