SIPPING D. Petrie
Internet-Draft SIPez LLC.
Intended status: Standards Track S. Channabasappa, Ed.
Expires: September 4, 2007 CableLabs
March 3, 2007
A Framework for Session Initiation Protocol User Agent Profile Delivery
draft-ietf-sipping-config-framework-11
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Abstract
This document defines a framework to enable configuration of Session
Initiation Protocol (SIP) User Agents in SIP deployments. The
framework provides a means to deliver profile data that User Agents
need to be functional, automatically and with minimal (preferably
none) User and Administrative intervention. The framework describes
how SIP User Agents can discover sources, request profiles and
receive notifications related to profile modifications. As part of
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this framework, a new SIP event package is defined for notification
of profile changes. The framework provides for multiple data
retrieval options, without requiring or defining retrieval protocols.
The framework does not include specification of the profile data
within its scope.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. Reference Model . . . . . . . . . . . . . . . . . . . . . 5
3.2. Data Model and Profile Types . . . . . . . . . . . . . . 9
3.3. Profile Life Cycle . . . . . . . . . . . . . . . . . . . 9
4. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4.1. Simple Deployment Scenario . . . . . . . . . . . . . . . 10
4.2. Devices supporting multiple users from different
Service Providers . . . . . . . . . . . . . . . . . . . . 12
5. Profile Delivery Framework . . . . . . . . . . . . . . . . . . 14
5.1. Profile Enrollment . . . . . . . . . . . . . . . . . . . 17
5.1.1. Creation of Enrollment Subscription . . . . . . . . . 17
5.1.2. Profile Enrollment Request Transmission . . . . . . . 24
5.1.3. Profile Enrollment Notification . . . . . . . . . . . 24
5.2. Profile Content Retrieval . . . . . . . . . . . . . . . . 25
5.3. Profile Change Operation . . . . . . . . . . . . . . . . 25
5.4. Profile Change Notification . . . . . . . . . . . . . . . 25
5.5. Additional Considerations . . . . . . . . . . . . . . . . 25
5.5.1. Manual retrieval of the Device Profile . . . . . . . . 26
5.5.2. Device Types . . . . . . . . . . . . . . . . . . . . . 26
5.5.3. Profile Data . . . . . . . . . . . . . . . . . . . . . 27
5.5.4. Profile Data Frameworks . . . . . . . . . . . . . . . 27
5.5.5. Additional Profile Types . . . . . . . . . . . . . . . 28
5.5.6. Deployment considerations . . . . . . . . . . . . . . 28
6. Event Package Definition . . . . . . . . . . . . . . . . . . . 28
6.1. Event Package Name . . . . . . . . . . . . . . . . . . . 29
6.2. Event Package Parameters . . . . . . . . . . . . . . . . 29
6.3. SUBSCRIBE Bodies . . . . . . . . . . . . . . . . . . . . 32
6.4. Subscription Duration . . . . . . . . . . . . . . . . . . 33
6.5. NOTIFY Bodies . . . . . . . . . . . . . . . . . . . . . . 33
6.6. Notifier Processing of SUBSCRIBE Requests . . . . . . . . 33
6.7. Notifier Generation of NOTIFY Requests . . . . . . . . . 34
6.8. Subscriber Processing of NOTIFY Requests . . . . . . . . 35
6.9. Handling of Forked Requests . . . . . . . . . . . . . . . 35
6.10. Rate of Notifications . . . . . . . . . . . . . . . . . . 35
6.11. State Agents . . . . . . . . . . . . . . . . . . . . . . 35
7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
7.1. Example 1: Device requesting profile . . . . . . . . . . 36
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7.2. Example 2: Device obtaining change notification . . . . . 39
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 43
8.1. SIP Event Package . . . . . . . . . . . . . . . . . . . . 43
8.2. New HTTP Event Header . . . . . . . . . . . . . . . . . . 43
9. Security Considerations . . . . . . . . . . . . . . . . . . . 44
9.1. Profile Enrollment and Change Notification . . . . . . . 47
9.2. Profile Content Retrieval . . . . . . . . . . . . . . . . 49
9.3. Profile Change Operation . . . . . . . . . . . . . . . . 50
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 51
11. Change History . . . . . . . . . . . . . . . . . . . . . . . . 51
11.1. Changes from
draft-ietf-sipping-config-framework-10.txt . . . . . . . 51
11.2. Changes from
draft-ietf-sipping-config-framework-09.txt . . . . . . . 52
11.3. Changes from
draft-ietf-sipping-config-framework-08.txt . . . . . . . 52
11.4. Changes from
draft-ietf-sipping-config-framework-07.txt . . . . . . . 53
11.5. Changes from
draft-ietf-sipping-config-framework-06.txt . . . . . . . 53
11.6. Changes from
draft-ietf-sipping-config-framework-05.txt . . . . . . . 54
11.7. Changes from
draft-ietf-sipping-config-framework-04.txt . . . . . . . 54
11.8. Changes from
draft-ietf-sipping-config-framework-03.txt . . . . . . . 54
11.9. Changes from
draft-ietf-sipping-config-framework-02.txt . . . . . . . 55
11.10. Changes from
draft-ietf-sipping-config-framework-01.txt . . . . . . . 55
11.11. Changes from
draft-ietf-sipping-config-framework-00.txt . . . . . . . 55
11.12. Changes from
draft-petrie-sipping-config-framework-00.txt . . . . . . 56
11.13. Changes from draft-petrie-sip-config-framework-01.txt . . 56
11.14. Changes from draft-petrie-sip-config-framework-00.txt . . 56
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 57
12.1. Normative References . . . . . . . . . . . . . . . . . . 57
12.2. Informative References . . . . . . . . . . . . . . . . . 58
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 58
Intellectual Property and Copyright Statements . . . . . . . . . . 60
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1. Introduction
SIP User Agents require configuration data to function properly.
Examples include network, device and user specific information.
Ideally, this configuration process should be automatic and require
minimal or no user intervention.
Many deployments of SIP User Agents require dynamic configuration and
cannot rely on pre-configuration. This framework provides a standard
means of providing dynamic configuration which simplifies deployments
containing SIP User Agents from multiple vendors.
This framework also addresses modifications to profiles and the
corresponding change notifications to the SIP User Agents using a new
event package. However, the framework does not define the content or
format of the actual profile data, leaving that to future
standardization activities.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC 2119 [RFC2119].
This document also reuses the SIP terminology defined in [RFC3261]
and [RFC3265], and specifies the usage of the following terms.
Device: software or hardware entity containing one or more SIP user
agents. It may also contain entities such as a DHCP client.
Device Provider: the entity responsible for managing a given device
Local Network Provider: the entity that controls the local network
to which a given device is connected
SIP Service Provider: the entity providing SIP services to users.
This can refer to private enterprises or public entities.
Profile: configuration data set specific to an entity (for example,
user, device, local network or other).
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Profile Type: a particular category of Profile data (for example,
User, Device, Local Network or other).
Profile Delivery Server (PDS): the source of a Profile, it is the
logical collection of the Profile Notification Component (PNC) and
the Profile Content Component(PCC).
Profile Notification Component (PNC): the logical component of a
Profile Delivery Server that is responsible for enrolling devices
and providing profile notifications.
Profile Content Component (PCC): the logical component of a Profile
Delivery Server that is responsible for storing, providing access
to, and accepting profile content.
3. Overview
This section provides an overview of the configuration framework. It
introduces the reference model and explains key concepts such as the
Profile Life Cycle and the Profile Types. It is meant to serve as a
reference section for the document, rather than providing a specific
logical flow of material, as it may be necessary to revisit these
sections for a complete understanding of this document. The detailed
framework for the profile delivery, presented in Section 5, is based
on the concepts introduced in this section.
3.1. Reference Model
The design of the framework was the result of a careful analysis to
identify the configuration needs of a wide range of SIP deployments.
As such, the reference model provides for a great deal of
flexibility, while breaking down the interactions to their basic
forms which can be reused in many different scenarios.
In its simplest form, the reference model for the framework defines
the interactions between the Profile Delivery Server(PDS) and the
device. The device needs the profile data to effectively function in
the network. The PDS is responsible for responding to device
requests and providing the profile data. The set of interactions
between these entities is referred to as the Profile Life Cycle.
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This reference model is illustrated in the diagram below.
+-------------------------+
+--------+ Interactions | Profile Delivery Server |
| Device |<==========================>| +---+ +---+ |
+--------+ (Profile Life Cycle) | |PNC| |PCC| |
| +---+ +---+ |
+-------------------------+
PNC = Profile Notification Component
PCC = Profile Content Component
Framework Reference Model
The PDS is subdivided into two logical components:
o Profile Notification Component (PNC), responsible for enrolling
devices in Profile event subscriptions and providing Profile
change notifications;
o Profile Content Component (PCC), responsible for storing,
providing access to, and accepting modifications related to
profile content.
SIP deployments vary considerably. For the sake of simplicity, two
deployment scenarios representing either end of the SIP deployment
spectrum are presented.
In the simplest scenario, a device connects through a network that is
controlled by a single provider who provides the local-network,
manages the devices, and offers services to the users. The Provider
propogates profile data to the device that contains all the necessary
information to obtain services in the network (including information
related to the local-network and the users). This is illustrated in
the following diagram.
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--------------
/ Local-network, \
| Device & Service |
\ Provider /
----------------
|
|
--------
| Device |
--------
|
|
----
|User|
----
Simple System Level Model
There are also deployments where the device can connect via a local
network that is not controlled by the SIP Service Provider, for
example, devices that connect via available public WiFi hotspots. In
such cases, Local Network Providers may wish to provide local network
information such as bandwidth constraints to the devices.
Devices may also be controlled by Device Providers that are
independent of the SIP Service Provider who provides user services,
for example, kiosks that allow users to access services anywhere. In
such cases the profile data may have to be obtained from different
profile sources: local network provider, device provider and SIP
service provider. This is indicated in the following diagram.
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--------
/ SIP \
| Service | -> Provides 'user' profile
| Provider | data (e.g., services
\ / configuration)
-------- --------
| / \
| | Device | -> Provides 'device' profile
| | Provider | data (e.g., device specifics)
| \ /
| ---------
| /
| / -------
| / / Local \
| / | Network |
| | | Provider | -> Provides 'local-network' profile
| | \ / data (e.g., bandwidth)
| | -------
| | /
| | /
| | |
===================
( Local Network )
===================
|
|
--------
| Device | -> Needs the 'local-network'
-------- and 'device' profile
/ \
/ \
------ ------
|User A| |User B| -> Users need 'user' profiles
------ ------
General System Level Model
As illustrated, the simplest deployments present a single profile
source whereas others may present multiple profile sources. To be
effective, a configuration framework needs to address various
deployment scenarios. To address a vast majority of deployments this
framework specifies three distinct profiles, each of which can be
obtained from a different provider, and a profile life cycle common
to any profile type.
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The understanding is that deployments in general will support the
defined profile types. However, the framework allows for flexibility
in specialized cases. The devices are required to support all the
three profile types, unless configured otherwise (at a minimum they
need to support the device profile). The deployments are required to
support the device profile, and user profiles for known users. In
the presence of multiple profiles, a retrieval order is specified for
the devices. Additional profiles may also be specified outside the
scope of this document, but are expected to follow the same profile
life cycle.
3.2. Data Model and Profile Types
This framework specifies the following three profiles. Additional
extended profiles may also be defined.
Local Network Profile: contains configuration data related to the
local network to which a device is directly connected. It is
expected to be provided by the Local Network Provider.
Device Profile: cContains configuration data related to a specific
device, provided by the Device Provider.
User Profile: contains configuration data related to a specific
User, as required to reflect that user's preferences and the
particular services subscribed to. It is expected to be provided
by the SIP Service Provider providing services.
3.3. Profile Life Cycle
Automated profile delivery requires proactive behavior on the part of
a device. It also requires one or more PDSs which provide the
profile data. The set of communications that results in profile
delivery is characterized by the profile life cycle. Each profile is
propogated using the profile life cycle.
The life cycle is initiated when the device enrolls for profile data.
Enrollment either results in profile data or in information
referencing content indirection. In the case of content indirection,
the provided retrieval procedures are used to retrieve the profile.
Additionally, the profile life cycle allows for profile change
operations by authorized entities. If a profile change operation is
successful, it results in profile change notifications to all
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enrolled devices.
The specific functional steps are as follows:
Profile Enrollment: the process by which a device requests, and if
successful, enrolls with a PDS capable of providing a profile. A
successful enrollment is indicated by a notification containing
the profile information (contents or content indirection
information). Depending on the request, this could also result in
a subscription to notification of profile changes.
Profile Content Retrieval: the process by which a device retrieves
profile contents, if the profile enrollment resulted in content
indirection information.
Profile Change Notification: the process by which a device is
notified of any changes to an enrolled profile. This may provide
the device with modified profile data or content indirection
information.
Profile Change Operation: The process by which an authorized entity
- such as a configuration management server or a device - pushes a
profile change to the PDS.
4. Use Cases
This section provides a small - non-comprehensive - set of
representative use cases to further illustrate how this Framework can
be utilized in SIP deployments. The first use case is simplistic in
nature, where as the second is relatively complex. The use cases
illustrate the effectiveness of the framework in either scenario.
For Security Considerations please refer to Section 9.
4.1. Simple Deployment Scenario
Description: Consider a deployment scenario (for example, a small
private enterprise) where a single entity enables the local network,
manages deployed devices and provides SIP services. The devices
never connect outside the local network and are each pre-configured
with a single user.
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The following assumptions apply:
o The device profile data contains all the information necessary
for the device to participate in the local network and obtain
services
o The device is pre-configured to only request the device profile
o The enrollment notification contains the profile data (profile
content retrieval is not required)
The following diagram illustrates this use case and highlights the
communications relevant to the framework specified in this document.
+----------------------+
+--------+ | Local Network, Device|
| Device | |& SIP Service Provider|
|(SIP UA)| | |
+--------+ | DHCP PDS |
+----------------------+
| | |
(A) |<============== DHCP =============>| |
| |
| |
| |
(B) |<=========== Profile Enrollment ============>|
| | Profile data
| | is modified
| | via "Profile
| | Change Operation"
| |
(C) |<============ Profile Change ================|
| Notification |
| |
| |
The following is an explanation of the interactions in the diagram.
(A) Upon initialization, the device obtains IP configuration
parameters using DHCP
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(B) The device performs Profile Enrollment for the device profile;
the device profile data is contained in the enrollment
notification
(C) Due to a modification of the device profile, a Profile Change
Notification is sent across to the device, along with the
modified profile
4.2. Devices supporting multiple users from different Service Providers
Description: Consider a single device (for example, Kiosk at an
airport) that allows for multiple users to obtain services from a
list of pre-configured SIP Service Providers.
The following assumptions apply:
o Provider A is the Device and Local Network Provider for the
device, and the SIP Service Provider for user A; Provider B is
the SIP Service Provider for user B
o Profile enrollment always results in content indirection
information requiring profile content retrieval
The following diagram illustrates the use case and highlights the
communications relevant to the framework specified in this document.
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User User
A B +----------------------+ +----------------------+
+--------+ | Provider | | Provider |
| Device | | A | | B |
|(SIP UA)| | | | |
+--------+ | DHCP PROXY PDS | | PROXY PDS |
+----------------------+ +----------------------+
| | | | | |
(A) |<====DHCP====>| | | | |
| | | | |
| | | | |
| Profile Enrollment | | | |
(B) |<local-network profile>|<====>| | |
|
| <<Profile content retrieval>>
|
|
| Profile Enrollment | | | |
(C) |<== device profile ==> |<====>| | |
|
| <<Profile content retrieval>>
|
.
.
.
[[User A obtains services]]
| Profile Enrollment | | | |
(D) |<= user profile (A) => |<====>| | |
| | | | |
|
| <<Profile content retrieval>>
.
.
.
.
[[User B obtains services]]
|
| Profile Enrollment | |
(E) |<=========== user profile (B) ==========>|<=========>|
| | |
| <<Profile content retrieval>>
|
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The following is an explanation of the interactions in the diagram.
(A) Upon initialization, the device obtains IP configuration
parameters using DHCP. This also provides the local domain
information to help with local-network profile enrollment
(B) The device requests profile enrollment for the local network
profile. It receives an enrollment notification containing
content indirection information from Provider A's PDS. The
device retrieves the profile (this contains useful information
such as firewall port restrictions and available bandwidth)
(C) The device then requests profile enrollment for the device
profile. It receives an enrollment notification resulting in
device profile content retrieval. The device initializes the
User interface for services.
(D) User A with a pre-existing subscription with Provider A attempts
communication via the user Interface. The device uses the user
supplied information (including any credential information) and
requests profile enrollment for user A's profile. Successful
enrollment and profile content retrieval results in services for
user A.
(E) At a different point in time, user B with a pre-existing
subscription with Provider B attempts communication via the user
Interface. It enrolls and retreives user B's profile and this
results in services for user B.
5. Profile Delivery Framework
This section details the framework requirements. The Profile Life
Cycle (introduced in Section 3), is examined in further detail, with
requirements that apply to the device and the PDS. Unless explicitly
enhanced or indicated by an implementing specification, the device
and the PDS MUST follow the Profile Life Cycle requirements stated in
this section for all supported profile types.
A high-level representation of the framework is shown in the
following state diagram. Each of the specified profile types is
retrieved individually, in the specified order (see below), until all
needed Profiles have been received.
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---------------
/ Device \
\ Initialization/
---------------
|
| Completes IP initialization;
| Initializes SIP stack
|
V
--------------
________\ / All profiles?\
| / \ retrieved? /
| --------------
| |
| | NO; attempt
| | Profile Request
| | in specified order
| |
| V
| ------------
___________/ Profile \
\ Life Cycle /
------------
Framework state diagram
The Profile Life Cycle, for each profile, is illustrated in the
diagram below.
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------------- { Device enrolls
/ Profile \ ...{ and obtains
\ Enrollment / { enrollment
------------- { notification
|
|
SUCCESS
|
|
...PDS... V ...DEVICE...
__________________________________
| |
| |
Active |
Subscription? |
(i.e, not a one |
time fetch) |
| |
| YES |
| |
V V
--------------
/ Profile Change \ __________________\ Content
\ Notification / / Indirection?
-------------- |
^ |
| | YES
| SUCCESS |
| V
-------------- ----------------
/ Profile Change\ / Profile Content \
\ Operation / \ Retrieval /
--------------- -----------------
The Profile Life Cycle is initiated when the device transmits an
enrollment request for a specific profile. If this is accepted, it
results in an enrollment notification that contains the profile data
or profile content indirection information. Unless the enrollment
request indicates a one-time profile request, it also results in
enrollment for profile change notifications. If the profile is
modified at any point in time, the profile change notification is
transmitted to the device. Notifications due to profile enrollment
or change operation may result in content indirection in which case
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the device uses profile content retrieval to obtain the profile data.
The Profile Life Cycle is the same for all the profile types, but
there are different requirements in each step based on the profile
types. This framework defines three profile types and an order that
MUST be followed by the device in requesting them (when it retrieves
two or more of the defined profile types), as follows:
o local-network
o device
o user
The sub-sections that follow specify the Profile Life Cycle details,
with specific requirements based on each profile type.
5.1. Profile Enrollment
The first step to obtaining a profile is PDS Enrollment. This is
initiated by the device and involves:
o creating a profile enrollment subscription
o transmitting a profile enrollment request
o receiving a profile enrollment notification
The processes are interlinked and retries encompass all three phases.
For example, if the enrollment request does not result in a profile
enrollment notification, the device is required to retry alternate
profile enrollment subscription creation options. Only when all the
enrollment subscription creation options are exhausted does the
device assume that the profile enrollment has failed. The processes
themselves are illustrated in the following sub-sections.
5.1.1. Creation of Enrollment Subscription
Each profile type requires its own subscription and based on the
entity requesting it, presents certain unique requirements (for
example, the device identifier is provided for the device profile
type where as the user identifier is provided for the user profile
type). Further, the profile types are aimed at different PDSs and
hence are identified differently (for example, the local-network is
identified by the local domain name where as the Service Provider is
identified based on the Service Provider's domain name). Some of
this information can be obtained in multiple ways (such as local
domain information that can be configured statically or dynamically)
and the device may have to try different information sources to
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obtain the required information (for example, dynamic configuration
can override statically configured information). Based on these
considerations, the framework defines different rules for obtaining
and presenting the information for each profile type. Additionally,
when more than one information source is possible for the
information, it is presented as well. This is highlighted in the
following sub-sections.
5.1.1.1. SIP SUBSCRIBE for the Local-Network profile type
Before attempting to create a SIP SUBSCRIBE requesting the local-
network profile, the device MUST have established local network
connectivity. It MUST also have knowledge of the local network
domain either via static configuration or dynamic discovery via
DHCPv4 ([RFC2131]) or DHCPv6 ([RFC3315]). The following requirements
apply:
o the user part of the Request URI MUST NOT be provided. The host
and port part of the Request URI MUST be set to the concatenation
of "sipuaconfig" and the local network domain
o a user AOR, if known to the device MUST be used to populate the
"From" field, unless privacy requirements prohibit its use (this
is useful if the user has privileges in the local network beyond
those of the default user)
o if a user AOR is not known, the user portion of the "From" field
MUST be set to "anonymous"; the host and port portion of the
Request URI MUST be set to the concatenation of "sipuaconfig" and
the local network domain
o the "device-id" event header parameter MUST be set to the device
identifier that the device will use to request the device profile
For example: If the device requested and received the local domain
name via DHCP to be: airport.example.net, then the Local-Network
Profile SUBSCRIBE Request URI would look like:
sip:sipuaconfig.airport.example.net
The Event header would look like the following if the device decided
to provide MAC%3a00DF1E004CD0@airport.example.net as the device
identifier. (Alice may have a prior arrangement with the local
network operator giving her special privileges.)
Event: ua-profile;profile-type=local-network;
device-id="sip:MAC%3a00DF1E004CD0@airport.example.net"
The local-network profile SUBSCRIBE Request URI does not have a user
part so that the URI is distinct between the "local" and "device"
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URIs when the domain is the same for the two. This provides a means
of routing to the appropriate PDS in domains where they are distinct
servers.
The From field is populated with the user AOR, if available. This
allows the local network provider to propagate user-specific profile
data, if available. The "device-id" event header parameter is set to
the device identifier. Even though every device may get the same (or
similar) Local-Network Profile, the uniqueness of the "device-id"
event header provides an important capability. Having unique From
fields allows the management of the local network to track devices
present in the network and consequently also manage resources such as
bandwidth and port allocation.
5.1.1.2. SIP SUBSCRIBE for the Device Profile Type
The device profile type allows the Service Provider managing a device
to provide device-specific configuration information. To enable
this, the Request URI needs to identify the device and the PDS domain
within which it is recognizable. Accordingly, this Framework
presents the following requirements for the formation of a
Subscription Request URI to request the "device" profile type
o the user portion of the Request URI MUST be set to a unique device
Identifier
o the host and port portion of the Request URI MUST be set to the
PDS domain
The following sub-sections explain identification of - and the
requirements related to - the device Identifier and the PDS domain
discovery.
5.1.1.2.1. Device Identifier
The device profile could be specific to each device in a SIP
deployment (for example, vendor/model) or shared across device types
(for example, based on services and service tiers). Further, the
same device might be provided different configuration profiles based
on deployment models. Device Identifiers play a significant role in
ensuring delivery of the correct profile and hence need to be unique
within a PDS domain to support the various deployment models.
This Framework requires that device Identifiers MUST be unique and
persistent over the lifetime of a device. Device Identifier
representations auto-generated by devices SHOULD be based on MAC
address or UUID ([RFC4122]) based representations. A device may use
alternate device identifiers (for example, SIP URIs) obtained via
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pre-configuration or dynamic configuration (for example, device
profile).
If a MAC address is used, the following requirements apply:
o the device identifier MUST be formatted as the characters "MAC:"
followed by a twelve digit hexadecimal upper case representation
of the MAC address to form a proper URN ([RFC2141]). The MAC
address representation MUST NOT include visual separators such as
colons and whitespaces. The representation is denoted using the
following ABNF syntax
mac-ident = MAC ":" 12UHEX
MAC = %x4d.41.43 ; MAC in caps
UHEX = DIGIT / %x41-46 ; uppercase A-F
o the MAC address MUST only be used to represent a single device.
It MUST NOT be used if more than one device can potentially use
the same MAC Address (for example, multiple software entities on a
single platform). In such cases, the UUID representation SHOULD
be used
If a UUID is used, the following requirements MUST apply:
o the same approach to defining a user agent Instance ID as
[RFC4122] MUST be used
o when the URN is used as the user part of the URI, it MUST be URL
escaped
The colon (":") is not a legal character (without being
escaped) in the user part of an addr-spec ([RFC4122]).
For example the instance ID:
urn:uuid:f81d4fae-7ced-11d0-a765-00a0c91e6bf6@example.com
would be escaped to look as follows in a URI:
sip:urn%3auuid%3af81d4fae-7ced-11d0-a765-00a0c91e6bf6@
example.com
The ABNF for the UUID representation is provided in [RFC4122]
5.1.1.2.2. PDS Domain Discovery
A device needs to identify the PDS domain to form the host and port
part of the Request URI. Ideally, this information should be
obtained via a single method. However, support for various
deployment models implies multiple device environments (for example,
residential routers, enterprise LANs, WLAN hotspots and dialup modem)
and presents hurdles to specifying a single method (for example, if a
device is always in the SIP Service Provider's network one could use
DHCP). To accommodate multiple deployment scenarios, the framework
specified in this document presents multiple approaches.
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Devices MUST follow the procedures specified below in the order
presented, unless exceptions are made by device manufacturers or
Device Providers who may provide an option for the user to choose the
order (to suit specific deployment models, for example).
1. Service Provider pre-configuration
The device MAY be pre-configured with information that can be
utilized to identify the host and port of the Request URI. The
information can be provided - as examples - when the device is
manufactured, by using Service Provider entities (flash card, SIM
card) or via a Service Provider specific method (for example,
information or methods that lead to self subscription). If the
device is specified to utilize this approach, it MUST attempt to
do so before trying other methods. The details of how this is
accomplished are beyond the scope of this document.
2. IP Configuration
If pre-configuration is not an option, or not available, IP
configuration MUST be utilized to try and obtain information that
can help with identification of the host and port for the Request
URI. The framework defines the following methods within this
procedure to accomplish this. device MUST follow the methods
defined, in the order specified, i.e. if the first option cannot
be accomplished or results in a failure, then next method is
tried. Failure of a specific method is indicated when the device
cannot successfully complete Profile Enrollment.
2a. DHCP option for SIP server:
Devices that support DHCP MUST attempt to obtain the host and
port of the outbound proxy during the DHCP process, using the
DHCP option for SIP servers defined in [RFC3361] or [RFC3319]
(for IPv4 and IPv6 respectively), and use these as the host and
port part of the request URI.
For example, a MAC based device identifier with a DHCP SIP
servers option indicating example.com, the Request URI would be
constructed as sip:MAC%3aABC123EFD456@example.com
2b. Local IP Network Domain:
- devices that support DHCP MUST attempt to obtain the local IP
network domain during the DHCP process, using DHCP option 15
and use these as the host and port part of the request URI
using the technique specificed in [RFC3263]
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+ For example, a MAC based devices identifier with a DHCP
option 15 indicating local.example.com, the Request URI
would be constructed as
sip:MAC%3aABC123EFD456@local.example.com
- If the local IP network domain is available (previous
method), but the usage of the local IP Network domain results
in a failure, the device MUST use the local IP network domain,
prefixing it using the label "sipuaconfig."
+ For example, a MAC based device Identifier with a DHCP
option 15 indicating local.example.com, the Request URI
would be constructed as
sip:MAC%3aABC123EFD456@sipuaconfig.local.example.com
3. Manual
If pre-configuration and IP Configuration are not options or
result in failures, the device SHOULD provide a means for the user
to present information that may help with the retrieval process.
Exceptions to this requirement MAY include devices with no user
interface appropriate for such entry.
This framework provides the following alternatives which can be
considered individually or together, in any order.
Device Provider PDS information: The user SHOULD be allowed to
present the host and port information which can help with the
creation of the Subscription URI to locate a PDS capable of
providing the profile.
Device Provider Configuration Server information The user MAY be
allowed to present information pertaining to a configuration
server that provides the device profile, not using a PDS as
defined in this framework. This framework specifies one such
possible process in Section 5.5.1.
5.1.1.3. SIP SUBSCRIBE for the User Profile Type
The user profile allows the responsible SIP Service Provider to
provide user-specific configuration. This is based on the user's
identity that is usually known in the network (for example,
associated with a subscription). Similar to the profiles provided to
devices, the content and propagation of user Profiles may partake
differently, based on deployment scenarios (for example, users
belonging to the same subscription might - or might not - be provided
the same profile). However, each user is uniquely identified in a
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SIP Service Provider's network using an Address Of Record (AOR).
Devices implementing this framework MUST use the user's AOR to
populate the Request URI.
A device MAY obtain the user's AOR using various methods such as pre-
configuration, via the device profile or dynamically via a user
Interface.
5.1.1.4. Caching of SIP Subscription URIs
Creation of Subscription URIs is vital for successful Profile
Enrollment. Unlike the user Profile - Local-Network and device
profiles are expected to be requested based on discovered information
(for example, domain name discovered via DHCP). These profile types
have different goals and hence, caching of the Subscription URI
should be carefully considered.
The Local-Network profile type is aimed at obtaining information from
the local network. The local network can change across device
initializations (for example, user moves the device from a home
network to a workplace LAN). Thus, the device SHOULD NOT remember
local-network profile subscription URIs across initializations. The
device SHOULD re-create the Subscription URI every time it moves to a
new network or gets re-initialized. Exceptions may be cases where
the device can unambiguously determine changes to the local network.
The device profile type is aimed at obtaining information from the
SIP Service Provider managing the device. Once established, the
Service Provider does not change often (an example of an exception
would be the re-use of devices across Service Providers). However,
if the discovery process is used, the device can only be sure of
having reached the Service Provider upon successful Profile
Enrollment and Profile Notification. Thus, the device SHOULD cache
the Subscription URI for the device profile. When cached, the device
should use the cached Subscription URI upon a reset. Exceptions
include cases where the device identifier has changed (for example,
new network card with a new MAC address), Service Provider
information has changed (for example, user initiates change) or the
device cannot obtain its profile using the Subscription URI.
Devices SHOULD NOT cache the Subscription URI for the device
profile type until successful Profile Notification. The reason
for this is that a PDS may send 202 responses to SUBSCRIBE
requests and NOTIFY responses to unknown devices (see Section 6.6)
with no profile data or URIs. Thus, successful Profile
Notification is the only sure way to know that the Subscription
URI is valid.
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5.1.2. Profile Enrollment Request Transmission
A device requesting a profile type specified in this document - and
is successful in forming a Subscription URI - MUST enroll using the
event package defined, and as specified, in this framework (see
Section 6) . The following requirements apply:
o the device MUST cater to the Event Package requirements specified
in Section 6.2 (for example, indicate the profile type being
requested in the profile-type parameter)
o the device MUST use the Subscription URI pertaining to the profile
type being requested, as specified in Section 5.1
The SIP infrastructure receiving such requests is expected to relay
and process profile enrollment requests. When a Profile Enrollment
request is received by a PDS, it SHOULD accept and respond to any
profile requests. Exceptions are when Service Provider policy
prevents such a response (for example, requesting entity is unknown).
Successful Profile Enrollment involves the following
o Acceptance of the SUBSCRIBE request by a PDS (indicated via a 200
response)
o Receipt of an initial Profile Notification within the timeouts as
specified in [RFC3265]
A device SHOULD follow suitable BackOff and Retry mechanisms if a
successful Profile Enrollment does not happen within the expected
period.
5.1.3. Profile Enrollment Notification
Successful Profile Enrollment is indicated by an enrollment
notification. This provides either a) the profile contents b)
content indirection information. If content indirection information
is provided, the device retrieves the profile using Profile Content
Retrieval. If the profile contents are provided, the following
requirements hold good:
o the device MUST make the new profiles effective within the
specified timeframe, as described in Section 6.2
o the device SHOULD cache (i.e. store persistently) the contents of
retrieved profiles, until overridden by subsequent Profile Change
Notifications (this avoids situations where a PDS is unavailable,
leaving the device without required configuration)
Failure to receive the initial NOTIFY following a successful
enrollment MUST be treated the same as a failed enrollment. In such
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a scenario, the device MUST retry using alternate methods for
creation of the enrollment subscription and transmit an enrollment
request. If all the enrollment subscription creation have been
exhausted, the device MUST treat it as a failure to obtain the
profile and take appropriate measures.
For NOTIFY content please refer to Section 6.5.
5.2. Profile Content Retrieval
Upon successful Profile Enrollment, the device can retrieve the
documents pertaining to the requested profile directly or via the
URI(s) provided in the NOTIFY request as specified in Section 6.5.
Profile Content Retrieval protocols and frameworks are out of scope
for this specification.
5.3. Profile Change Operation
Configuration Profiles can change over time. Modifications can be
initiated by various entities (for example, via the device, back-
office components and end-user web interfaces for configuration
servers) and for various reasons (such as, change in user
preferences, modifications to services, enterprise-imposed common
features or restrictions). This framework allows for such changes to
be communicated to the PDS, using the term Profile Change Operation.
Any changes to a Profile as a result of Profile Change Operation MUST
result in a Profile Notification to all enrolled devices for that
Profile, if any.
Definition of specific mechanisms for Profile Change Operation are
out of scope of this document.
5.4. Profile Change Notification
Whenever a profile is changed, a PDS compliant with this framework
MUST NOTIFY all the devices currently subscribed to the profile under
consideration. This process is termed Profile Change Notification.
For NOTIFY content please refer to Section 6.5.
5.5. Additional Considerations
This section provides a special case for retrieval of the device
profile and highlights considerations and requirements on external
entities such as Profile Data Frameworks.
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5.5.1. Manual retrieval of the Device Profile
At a minimum, a device requires the device profile to be able to
function effectively. However, the methods specified in this
document may fail to provide a device with a profile. To illustrate
with an example, consider the case of a device that finds itself
behind a local network which does not provide information about DNS
servers in the network (for example, misconfigured home network). In
such cases, it would be beneficial to employ an alternative means to
obtain the profile information (for example, resolvable DNS Servers
could be part of the device profile). While this specification
recommends that such a method be made available, it also specifies
one such option using HTTP that is described in this sub-section.
devices expected to encounter scenarios where propogation of the
device profile can be hindered may employ the specified - or any
alternative - process.
The method being described involves the device to utilize a HTTPS URI
(and any required credentials) based on either pre-configuration or
manual entry by the user (in cases where such an interface is
possible). This can lead to the retrieval of the device profile
which may contain the properties for the SUBSCRIBE Request URI and
credentials for Profile Enrollment and Profile Notification. This
approach bootstraps the process in a different step in the cycle, but
uses the same framework.
Further, this document defines a new HTTP request header "Event".
The syntax of the HTTP Event header is the same as the SIP Event
header defined in this document. Similar to the SIP Event header the
purpose of the HTTP Event header is to define the content of the
state information to be retrieved. In particular, the state
information is the device, user or local-network profile for the
device. The SIP Event header parameters for this event package
("profile-type", "vendor", "model", "version") are also mandatory for
the HTTP Event header as they are used to provide information as to
what profile type is requested along with information about the
device which may impact the contents of the profile. When the 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 defined.
5.5.2. Device Types
The examples in this framework tend to associate devices with
entities that are accessible to end-users. However, this is not
necessarily the only type of device that can utilize the specified
Framework. devices can be entities such as user Interfaces (that
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allow for device Configuration), entities in the network that do not
directly communicate with any users (for example, Service Provider
deployed gateways) or elements in the Service Provider's network (for
example, SIP servers).
5.5.3. Profile Data
This framework does not specify the contents for any profile type.
Follow-on standardization activities can address profile contents.
However, it makes the following assumptions and recommendations:
o When the device receives multiple profiles, the contents of each
profile type will only contain data relevant to the entity it
represents. As an example, consider a device that obtains all the
defined profiles. Information pertaining to the local network is
contained in the 'local-network' profile and not the'user'
profile. This does not preclude relevant data about a different
entity from being included in a profile type, for example, the
'device' profile type may contain information about the users
allowed to access services via the device. A profile may also
contain starting information to obtain subsequent Profiles
o Data overlap SHOULD be avoided across profile types, unless
necessary. If data overlap is present, prioritization of the data
is left to data definitions. As an example, the device profile
may contain the list of codecs to be used by the device and the
user Profile (for a user on the device) may contain the codecs
preferred by the user. Thus, the same data (usable codecs) is
present in two profiles. However, the data definitions may
indicate that to function effectively, any codec chosen for
communication needs to be present in both the profiles.
5.5.4. Profile Data Frameworks
This framework specified in this document does not address profile
data representation, storage or retrieval protocols. It assumes that
the PDS has a PCC based on existing or other Profile Data Frameworks,
for example, XCAP ([I-D.ietf-simple-xcap]).
While it does not impose vast constraints on any such framework, it
does allow for the propagation of profile content to PDS
(specifically the PCC). Thus, Profile Data or Retrieval frameworks
used in conjunction with this framework MAY consider techniques for
propagating incremental, atomic changes to the PDS. For example, a
means for propagating changes to a PDS is defined in XCAP
([I-D.ietf-simple-xcap]).
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5.5.5. Additional Profile Types
This document specifies three profile types: local-network, device
and user. However, there may be use cases for additional profile
types. For example, profile types for application specific profile
data. Definition of such additional profile types is not prohibited,
but considered out of scope for this document.
5.5.6. Deployment considerations
The framework defined in this document was designed to address
various deployment considerations, some of which are highlighted
below.
Provider relationships:
o The local network provider and the SIP service provider can often
be different entities, with no administrative or business
relationship with each other;
o There may be multiple SIP service providers involved, one for each
service that a user subscribes to (telephony service, instant
messaging, etc.); this Framework does not specify explicit
behavior in such a scenario, but it does not prohibit its usage
either
o Each user accessing services via the same device may subscribe to
different sets of services, from different Service Providers;
User-device relationship:
o The relationship between devices and users can be many-to-many
(for example, a particular device may allow for many users to
obtain subscription services through it, and individual users may
have access to multiple devices);
o Each user may have different preferences for use of services, and
presentation of those services in the device user interface;
o Each user may have different personal information applicable to
use of the device, either as related to particular services, or
independent of them.
6. Event Package Definition
The framework specified in this document proposes and specifies a new
SIP Event Package as allowed by [RFC3265]. The purpose is to allow
for devices to subscribe to specific profile types with PDSs and for
the PDSs to notify the devices with - or pointers to - profile data.
The requirements specified in [RFC3265] apply to this package. The
following sub-sections specify the Event Package description and the
associated requirements. The framework requirements are defined in
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Section 5.
6.1. Event Package Name
The name of this package is "ua-profile". This value appears in the
Event header field present in SUBSCRIBE and NOTIFY requests for this
package as defined in [RFC3265].
6.2. Event Package Parameters
This package defines the following new parameters for the event
header:
"profile-type", "vendor", "model", "version", "effective-by",
"device-id" and "network-user".
The following rules apply:
o All the new parameters, with the exception of the "effective-by"
parameter MUST only be used in SUBSCRIBE requests and ignored if
they appear in NOTIFY requests
o The "effective-by" parameter is for use in NOTIFY requests only
and MUST be ignored if it appears in SUBSCRIBE requests
The semantics of these new parameters are specified in the following
sub-sections.
6.2.1. profile-type
The "profile-type" parameter is used to indicate the token name of
the profile type the user agent wishes to obtain data or URIs for and
to be notified of subsequent changes. This document defines three
logical types of profiles and their token names. They are as
follows:
local-network Specifying "local-network" type profile indicates the
desire for profile data (URI when content indirection is used)
specific to the local network.
device Specifying "device" type profile(s) indicates the desire for
the profile data (URI when content indirection is used) and change
notification of the contents of the profile that is specific to
the device or user agent.
user Specifying "user" type profile indicates the desire for the
profile data (URI when content indirection is used) and change
notification of the profile content for the user.
The "profile-type" is identified is identified in the Event header
parameter: profile-type. A separate SUBSCRIBE dialog is used for
each profile type. The profile type associated with the dialog can
then be used to infer which profile type changed and is contained in
the NOTIFY or content indirection URI. The Accept header of the
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SUBSCRIBE request MUST include the MIME types for all profile content
types for which the subscribing user agent wishes to retrieve
profiles or receive change notifications.
In the following syntax definition using ABNF, EQUAL and token are
defined in [RFC3261]. It is to be noted that additional profile
types may be defined in subsequent documents.
Profile-type = "profile-type" EQUAL profile-value
profile-value = profile-types / token
profile-types = "device" / "user" / "local-network"
The "device", "user" or "local-network" token in the profile-type
parameter may represent a class or set of profile properties.
Follow-on standards defining specific profile contents may find it
desirable to define additional tokens for the profile-type parameter.
Also additional content types may be defined along with the profile
formats that can be used in the Accept header of the SUBSCRIBE to
filter or indicate what data sets of the profile are desired.
6.2.2. vendor, model and version
The "vendor", "model" and "version" parameter values are tokens
specified by the implementer of the user agent. These parameters
MUST be provided in the SUBSCRIBE request for all profile types. The
implementer SHOULD use their DNS domain name (for example,
example.com) as the value of the "vendor" parameter so that it is
known to be unique. These parameters are useful to the PDS to affect
the profiles provided. In some scenarios it is desirable to provide
different profiles based upon these parameters. For example, feature
property X in a profile may work differently on two versions of the
same user agent. This gives the PDS the ability to compensate for or
take advantage of the differences. In the following ABNF defining
the syntax, EQUAL and quoted-string are defined in [RFC3261].
Vendor = "vendor" EQUAL quoted-string
Model = "model" EQUAL quoted-string
Version = "version" EQUAL quoted-string
6.2.3. device-id
The "device-id" parameter MUST be set when subscribing for "local-
network" profiles. This identifies the device requesting the local-
network profile.
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If the value of the "profile-type" parameter is not "local-network",
the "device-id" parameter has no defined meaning and is ignored. In
the following ABNF, EQUAL, LDQUOT, RDQUOT and addr-spec are defined
in [RFC3261].
Device-Id = "device-id" EQUAL LDQUOT addr-spec RDQUOT
6.2.4. network-user
The "network-user" parameter MAY be provided in a subscription for a
"device" profile. In such cases the device is requesting the PDS to
recognize the indicated user as the default user for itself.
If the value of the "profile-type" parameter is not "device", the
"network-user" parameter has no defined meaning and is ignored. If
the "network-user" parameter is provided in the SUBSCRIBE request, it
MUST be present in the NOTIFY request as well. In the following
ABNF, EQUAL, LDQUOT, RDQUOT and addr-spec are defined in [RFC3261].
Network-User = "network-user" EQUAL LDQUOT addr-spec RDQUOT
6.2.5. effective-by parameter
The "effective-by" parameter in the Event header of the NOTIFY
request specifies the maximum number of seconds before the user agent
must attempt to make the new profile effective. The "effective-by"
parameter MAY be provided in the NOTIFY request for any of the
profile types. A value of 0 (zero) indicates that the subscribing
user agent must attempt to make the profiles effective immediately
(despite possible service interruptions). This gives the PDS the
power to control when the profile is effective. This may be
important to resolve an emergency problem or disable a user agent
immediately. The "effective-by" parameter is ignored in all messages
other than the NOTIFY request. In the following ABNF, EQUAL and
DIGIT are defined in [RFC3261].
Effective-By = "effective-by" EQUAL 1*DIGIT
6.2.6. Summary of event parameters
The following are example Event headers which may occur in SUBSCRIBE
requests. These examples are not intended to be complete SUBSCRIBE
requests.
Event: ua-profile;profile-type=device;
vendor="vendor.example.com";model="Z100";version="1.2.3"
Event: ua-profile;profile-type="user";
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vendor="premier.example.com";model="trs8000";version="5.5"
The following are example Event headers which may occur in NOTIFY
requests. These example headers are not intended to be complete
SUBSCRIBE requests.
Event: ua-profile;effective-by=0
Event: ua-profile;effective-by=3600
The following table shows the use of Event header parameters in
SUBSCRIBE requests for the three profile types:
profile-type || device | user | local-network
=============================================
vendor || m | m | m
model || m | m | m
version || m | m | m
device-id || | | m
network-user || o | |
effective-by || | |
m - mandatory
s - SHOULD be provided
o - optional
Non-specified means that the parameter has no meaning and should be
ignored.
The following table shows the use of Event header parameters in
NOTIFY requests for the three profile types:
profile-type || device | user | local-network
=============================================
vendor || | |
model || | |
version || | |
device-id || | | o
network-user || o | |
effective-by || o | o | o
6.3. SUBSCRIBE Bodies
This package defines no use of the SUBSCRIBE request body. If
present, it MUST be ignored.
Future enhancements to the framework may specify a use for the
SUBSCRIBE request body (for example,, mechanisms using etags to
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minimize Profile Notifications to devices with current profile
versions).
6.4. Subscription Duration
The duration of a subscription is specific to SIP deployments and no
specific recommendation is made by this Event Package. If absent, a
value of 86400 seconds is RECOMMENDED since the presence (or absence)
of a device subscription is not time critical to the regular
functioning of the PDS.
It is to be noted that a one-time fetch of a profile can be
accomplished by setting the 'Expires' parameter to a value of Zero,
as specified in [RFC3265].
6.5. NOTIFY Bodies
The framework specifying the Event Package allows for the NOTIFY body
to contain the profile data or a pointer to the profile data using
content indirection. The framework does not define any profile data
and delegates specification of utilized MIME types Profile Data
Frameworks. For profile data delivered via content indirection, the
following apply:
o the Content-ID MIME header, as described in [RFC4483] MUST be used
for each Profile document URI
o at a minimum, the "http:" and "https:" URI schemes MUST be
supported; other URI schemas MAY be supported based on the Profile
Data Frameworks (examples include FTP [RFC0959], HTTP [RFC2616],
HTTPS [RFC2818], LDAP [RFC4510], XCAP [I-D.ietf-simple-xcap],
XCAP-DIFF [I-D.ietf-simple-xcap-diff])
The NOTIFY body SHOULD include a MIME type specified in the 'Accept'
header of the SUBSCRIBE. Further, if the Accept header of the
SUBSCRIBE included the MIME type message/external-body (indicating
support for content indirection) the content indirection SHOULD be
used in the NOTIFY body for providing the profiles. If none are
specified, the Profile Data frameworks are responsible for, and MUST
specify, the MIME type to be assumed.
6.6. Notifier Processing of SUBSCRIBE Requests
A successful SUBSCRIBE request results in a NOTIFY with either
profile contents or a pointer to it (via Content Indirection). If
the NOTIFY is expected to contain profile contents or the Notifier is
unsure, the SUBSCRIBE SHOULD be either authenticated or transmitted
over an integrity protected SIP communication channels. Exceptions
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to authenticating such SUBSCRIBEs include cases where the identity of
the Subscriber is unknown and the Notifier is configured to accept
such requests.
The Notifier MAY also authenticate SUBSCRIBE messages even if the
NOTIFY is expected to only contain a pointer to profile data.
Securing data sent via Content Indirection is covered in Section 9.
If the profile type indicated in the "profile-type" Event header
parameter is unavailable or the Notifier is configured not to provide
it, the Notifier SHOULD return a 404 response to the SUBSCRIBE
request. If the specific user or device is unknown, the Notifier MAY
either accept or reject the subscription.
When the Event header "profile-type" is "device" and the user agent
has provided the user's AOR in the "network-user" parameter, the
profile delivery server MAY set or change the default user associated
with the device indicated in the Subscription request. However, the
Notifier SHOULD authenticate the user indicated before making such a
change.
6.7. Notifier Generation of NOTIFY Requests
As specified in [RFC3265], the Notifier MUST always send a NOTIFY
request upon accepting a subscription. If the device or user is
unknown and the Notifier choose to accept the subscription, the
Notifier MAY either respond with profile data (for example, default
profile data) or provide no profile information (i.e. no body or
content indirection).
If the URI in the SUBSCRIBE request is a known identity and the
requested profile information is available (i.e. as specified in the
profile-type parameter of the Event header), the Notifier SHOULD send
a NOTIFY with profile data. Profile data MAY be sent as profile
contents or via Content Indirection (if the content indirection MIME
type was included in the Accept header). To allow for Content
Indirection, the Subscriber MUST support the "http:" or "https:" URI
schemas. If the Subscriber wishes to support alternative URI schemas
it MUST be indicated in the "schemes" Contact header field parameter
as defined in [RFC4483]. If the subscriber does not specify the URI
scheme, the Notifier may use either "http:" or "https:".
The Notifier MAY specify when the new profiles must be made effective
by the Subscriber by specifying a maximum time in seconds (zero or
more) in the "effective-by" event header parameter.
If the SUBSCRIBE was received over an integrity protected SIP
communications channel, the Notifier SHOULD send the NOTIFY over the
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same channel.
6.8. Subscriber Processing of NOTIFY Requests
A Subscriber to this event package MUST adhere to the NOTIFY request
processing behavior specified in [RFC3265]. If the Notifier
indicated an effective time (using the "effective-by" Event Header
parameter), it SHOULD attempt to make the profiles effective within
the specified time. Exceptions include deployments that prohibit
such behavior in certain cases (for example, emergency sessions are
in progress). When profile data cannot be applied within the
recommended timeframe and this affects device behavior, any actions
to be taken SHOULD be defined by the profile data definitions. By
default, the Subscriber is RECOMMENDED to make the profiles effective
as soon as possible.
The Subscriber MUST always support "http:" or "https:" and be
prepared to accept NOTIFY messages with those URI schemas.The
subscriber MUST also be prepared to receive a NOTIFY request with no
body. The subscriber MUST NOT reject the NOTIFY request with no
body. The subscription dialog MUST NOT be terminated by a NOTIFY
with no body.
6.9. Handling of Forked Requests
This Event package allows the creation of only one dialog as a result
of an initial SUBSCRIBE request as described in section 4.4.9 of
[RFC3265]. It does not support the creation of multiple
subscriptions using forked SUBSCRIBE requests.
6.10. Rate of Notifications
The rate of notifications for the profiles in this framework is
deployment specific, but expected to be infrequent. Hence, the Event
Package specification does not specify a throttling or minimum period
between NOTIFY requests
6.11. State Agents
State agents are not applicable to this Event Package.
7. Examples
This section provides examples along with sample SIP message bodies
relevant to this framework. Both the examples are derived from a
snapshot of Section 4.1, specifically the request for the device
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profile. The examples are purely informative and in case of
conflicts with the framework or protocols used for illustration, the
latter should be deemed normative.
7.1. Example 1: Device requesting profile
This example illustrates the detailed message flows between the
device and the SIP Service Provider's network for requesting and
retrieving the profile (the flow uses the device profile as an
example).
The following are assumed for this example:
o Device is assumed to have established local network connectivity;
NAT and Firewall considerations are assumed to have been addressed
by the SIP Service Provider
o examples are a snapshot only and do not illustrate all the
interactions between the device and the Service Provider's network
(and none between the entities in the SIP Service Provider's
network)
o All SIP communication with the SIP Service Provider happens via a
SIP Proxy
o HTTP is assumed to be the Profile Data method used (any suitable
alternative can be used as well)
o TLS is assumed to be the protocol for securing the Profile Content
Retrieval (any other suitable protocol can be employed);
authentication and security requirements are not addressed
The flow diagram and an explanation of the messages follow.
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+----------------------+
+--------+ | SIP Service Provider |
| Device | | |
|(SIP UA)| | SIP PDS HTTP |
+--------+ | PROXY Server |
| |
+----------------------+
| | | |
| | | |
| SUBSCRIBE | | |
(SReq)|--------device profile--------->| | |
| |------>| |
| |200 OK | |
| 200 OK |<------| |
(SRes)|<-------------------------------| | |
| | | |
| | NOTIFY| |
| NOTIFY (Content Indirection)|<------| |
(NTFY)|<-------------------------------| | |
| 200 OK | | |
(NRes)|------------------------------->|200 OK | |
| |------>| |
| |
| |
| |
|<<<<<<<<<<<<< TLS establishment >>>>>>>>>>>>>|
| |
| HTTP Request |
(XReq)|---------------------------------------------->|
| |
| HTTP Response |
(XRes)|<----------------------------------------------|
| |
(SReq)
the device transmits a request for the 'device' profile using the
SIP SUBSCRIBE utilizing the Event Package specified in this
framework.
* Note: Some of the header fields (for example, Event, via) are
continued on a separate line due to format constraints of
this document
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SUBSCRIBE sip:MAC%3a000000000000@sip.example.net SIP/2.0
Event: ua-profile;profile-type=device;vendor="vendor.example.net";
model="Z100";version="1.2.3";network-user="sip:user@sip.example.net"
From: sip:MAC%3A000000000000@sip.example.net;tag=1234
To: sip:MAC%3A000000000000@sip.example.net
Call-ID: 3573853342923422@192.0.2.44
CSeq: 2131 SUBSCRIBE
Contact: sip:MAC%3A000000000000@sip.example.net
Via: SIP/2.0/TCP 192.0.2.41;
branch=z9hG4bK6d6d35b6e2a203104d97211a3d18f57a
Accept: message/external-body, application/x-z100-device-profile
Content-Length: 0
(SRes)
the SUBSCRIBE request is received by a SIP Proxy in the Service
Provider's network which transmits it to the PDS. The PDS accepts
the response and responds with a 200 OK
* Note: The device and the SIP proxy may have established a
secure communications channel (for example, TLS)
(NTFY)
subsequently, the PDS transmits a SIP NOTIFY message indicating
the profile location
* Note: Some of the fields (for example, content-type) are
continued on a separate line due to format constraints of this
document
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NOTIFY sip:MAC%3A000000000000@192.0.2.44 SIP/2.0
Event: ua-profile;effective-by=3600
From: sip:MAC%3A000000000000@sip.example.net;tag=abca
To: sip:MAC%3A000000000000@sip.example.net;tag=1231
Call-ID: 3573853342923422@192.0.2.44
CSeq: 322 NOTIFY
Via: SIP/2.0/UDP 192.0.2.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d0
MIME-Version: 1.0
Content-Type: message/external-body; access-type="URL";
expiration="Mon, 01 Jan 2010 09:00:00 UTC";
URL="http://sip.example.net/z100-000000000000.html";
size=9999;
hash=10AB568E91245681AC1B
Content-Type: application/x-z100-device-profile
Content-ID: <39EHF78SA@sip.example.net>
.
.
.
(NRes)
Device accepts the NOTIFY message and responds with a 200 OK
(XReq)
once the necessary secure communications channel is established,
the device sends an HTTP request to the HTTP server indicated in
the NOTIFY
(XRes)
the HTTP server responds to the request via a HTTP response
containing the profile contents
7.2. Example 2: Device obtaining change notification
The following example illustrates the case where a user (X) is
simultaneously accessing services via two different devices (for
example, Multimedia entities on a PC and PDA) and has access to a
user Interface (UI) that allows for changes to the user profile.
The following are assumed for this example:
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o The devices (A & B) obtain the necessary profiles from the same
SIP Service Provider
o The SIP Service Provider also provides a user Interface (UI) that
allows the user to change preferences that impact the user profile
The flow diagram and an explanation of the messages follow.
o Note: The example only shows retrieval of user X's profile, but it
may request and retrieve other profiles (for example, local-
network, Device).
----- -----
|User |_________| UI* | * = User Interface
| X | | |
----- -----
/ \
/ \
/ \ +----------------------+
+--------+ +--------+ | SIP Service Provider |
| Device | | Device | | |
| A | | B | | SIP PDS HTTP |
+--------+ +--------+ | PROXY Server |
+----------------------+
| | | |
| | | |
(A-EX)|<=Enrolls for User X's profile=>|<=====>| |
| | | |
| |
(A-RX)|<===Retrieves User X's profile================>|
| |
| | | | |
| | Enrolls for | | |
| (B-EX)|<== User X's ==>|<=====>| |
| | profile | | |
| | | | |
| | |
| (B-RX)|<= Retrieves User X's profile=>|
| |
| | |
| (HPut)|---------------------->|
| | |
| (HRes)|<----------------------|
| |
| | | |
| | NOTIFY| |
| NOTIFY |<------| |
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(A-NT)|<-------------------------------| | |
| 200 OK | | |
(A-RS)|------------------------------->|200 OK | |
| |------>| |
| |
| | | NOTIFY| |
| | NOTIFY |<------| |
| (B-NT)|<---------------| | |
| | 200 OK | | |
| (B-RS)|--------------->|200 OK | |
| | |------>| |
| |
| |
(A-RX)|<===Retrieves User X's profile================>|
| |
| | |
| | |
| (B-RX)|<= Retrieves User X's profile=>|
| | |
(A-EX) Device A discovers, enrolls and obtains notification related
to user X's profile
(A-RX) Device A retrieves user X's profile
(B-EX) Device B discovers, enrolls and obtains notification related
to user X's profile
(B-RX) Device B retrieves user X's profile
(HPut) Changes affected by the user via the user Interface (UI) are
uploaded to the HTTP Server
* Note: The UI itself can act as a device and subscribe to user
X's profile. This is not the case in the example shown.
(HRes) Changes are accepted by the HTTP server
(A-NT) PDS transmits a NOTIFY message to device A indicating the
changed profile. A sample message is shown below:
Note: Some of the fields (for example, Via) are continued on a
separate line due to format constraints of this document
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NOTIFY sip:userX@192.0.2.44 SIP/2.0
Event: ua-profile;effective-by=3600
From: sip:userX@sip.example.net;tag=abcd
To: sip:userX@sip.example.net.net;tag=1234
Call-ID: 3573853342923422@192.0.2.44
CSeq: 322 NOTIFY
Via: SIP/2.0/UDP 192.0.2.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d1
MIME-Version: 1.0
Content-Type: message/external-body; access-type="URL";
expiration="Mon, 01 Jan 2010 09:00:00 UTC";
URL="http://www.example.com/user-x-profile.html";
size=9999;
hash=123456789AAABBBCCCDD
.
.
.
(A-RS) Device A accepts the NOTIFY and sends a 200 OK
(B-NT) PDS transmits a NOTIFY message to device B indicating the
changed profile. A sample message is shown below:
Note: Some of the fields (for example, Via) are continued on a
separate line due to format constraints of this document
NOTIFY sip:userX@192.0.2.43 SIP/2.0
Event: ua-profile;effective-by=3600
From: sip:userX@sip.example.net;tag=abce
To: sip:userX@sip.example.net.net;tag=1235
Call-ID: 3573853342923422@192.0.2.43
CSeq: 322 NOTIFY
Via: SIP/2.0/UDP 192.0.2.3;
branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d2
MIME-Version: 1.0
Content-Type: message/external-body; access-type="URL";
expiration="Mon, 01 Jan 2010 09:00:00 UTC";
URL="http://www.example.com/user-x-profile.html";
size=9999;
hash=123456789AAABBBCCCDD
.
.
.
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(B-RS) Device B accepts the NOTIFY and sends a 200 OK
(A-RX) Device A retrieves the updated profile pertaining to user X
(B-RX) Device B retrieves the updated profile pertaining to user X
8. IANA Considerations
There are two IANA considerations associated with this document, SIP
Event Package and HTTP header. These are outlined in this section.
8.1. SIP Event Package
This specification registers a new event package as defined in
[RFC3265]. The following information required for this registration:
Package Name: ua-profile
Package or Template-Package: This is a package
Published Document: RFC XXXX (Note to RFC Editor: Please fill in
XXXX with the RFC number of this specification).
Persons to Contact: Daniel Petrie dan.ietf AT SIPez DOT com,
sumanth@cablelabs.com
New event header parameters: profile-type, vendor, model, version,
effective-by, device-id, network-user (the profile-type parameter
has predefined values. The new event header parameters do not)
The following table illustrates the additions to the IANA SIP Header
Field Parameters and Parameter Values: (Note to RFC Editor: Please
fill in XXXX with the RFC number of this specification)
Predefined
Header Field Parameter Name Values Reference
---------------------------- --------------- --------- ---------
Event profile-type Yes [RFCXXXX]
Event vendor No [RFCXXXX]
Event model No [RFCXXXX]
Event version No [RFCXXXX]
Event effective-by No [RFCXXXX]
Event device-id No [RFCXXXX]
Event network-user No [RFCXXXX]
8.2. New HTTP Event Header
This document defines a new permanent HTTP request header field:
Event.
Header field name: Event
Applicable protocol: http
Status: standard
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Author/Change controller: IETF
Specification document(s): [RFCXXXX] (Note to RFC Editor: Please
fill in XXXX with the RFC number of this specification).
9. Security Considerations
The framework specified in this document allows for the propagation
of device profile data (Section 5.5.3). To accomplish this, it
specifies a Profile Life Cycle (Section 3.3) and an Event Package
(Section 6).
The Profile Life Cycle consists of three distinct communication
channels: Profile Enrollment and Change Notification, Profile Content
Retrieval, and Profile Change Operation.
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+------+ +-----+
| | | |
|Device| | PNC |
| | | |
+------+ +-----+
| |
| Profile Enrollment |
|---------------------->|
| |
| Profile Notification | (initial
|<----------------------| or upon
| | a change)
+------+ +-----+
| | | |
|Device| | PCC |
| | | |
+------+ +-----+
| |
| Profile Request | (When content
|---------------------->| indirection
| | is used)
| Profile Response |
|<----------------------|
| |
+------------+ +-----+
| Authorized | | PCC |
| Entity | | |
+------------+ +-----+
| |
| |
| Profile Change Request |
|---------------------------------->|
| |
| Profile Change Response |
|<----------------------------------|
| |
PNC = Profile Notification Component
PCC = Profile Content Component
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Framework Reference Model
Profile enrollment and change notification allows a device to
transmit a request for a specific profile - relayed directly, or via
one or more SIP proxies - to a PNC. If the PNC accepts the profile
request, it transmits a Profile Notification that contains either:
profile data or content indirection information. The profile data
can contain information specific to an entity (such as the device or
a user) and may contain sensitive information (such as service
credentials). Compromise of such data can lead to threats such as
impersonation attacks (establishing rogue sessions), theft of service
(if services are obtainable), and zombie attacks. Even if the
profile data is provided using content indirection, PCC information
within the notification can lead to threats such as denial of service
attacks (rogue devices bombard the PCC with requests for a specific
profile) and attempts to modify erroneous data onto the PCC (since
the location and format may be known). It is also important for the
device to ensure the authenticity of the PNC since impersonation of
the Service Provider can lead to Denial of Service, Man-in-the-Middle
attacks, etc.
Profile Content retrieval allows a device to retrieve profile data
from a PCC. This communication is accomplished using one of many
profile delivery protocols or frameworks, but is considered to be out
of scope within this document. However, since the profile data
returned is subject to the same considerations as that sent via
profile notification, the same threats exist.
Profile Change Operation allows an authorized entity to modify
profiles stored on a PCC. The specific entities are based on Service
Provider's policy and can include trusted network elements and
devices alike. The profile information stored on a PCC can contain
information that directs device and user behavior, services offered
and may contain sensitive information such as credentials. Thus,
allowing entities that are not trusted to perform profile
modifications presents threats such as denial-of-service,
manipulation of service, impersonation (for example, redirection to
rogue networks) and man-in-the-middle attacks.
The framework specified in this document accomplishes the propagation
of profile data by utilizing the specified "ua-profile" event package
which is based on [RFC3265]. Thus, its usage is expected to comply
with the security considerations and requirements (access control,
Notifier privacy mechanism, Denial-of-Service attacks, replay
attacks, and Man-in-the Middle attacks) specified in Section 5 of
[RFC3265]. The remainder of this section presents the specific
security requirements for the framework.
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9.1. Profile Enrollment and Change Notification
This framework specifies, and allows for the propagation of, three
profile types: local-network, device and user. Enrollment and change
notification are expected to be accomplished over integrity-protected
SIP communication channels and following requirements are presented:
o devices and PNCs complying with this framework MUST implement TLS
as specified in [RFC3268], including support for both mutual and
one-way authentication (server-side)
o devices and PNCs complying with this framework MUST implement the
SIP Digest authentication scheme as specified in [RFC3261]
o a PNC capable of propagating device and user profiles MUST contain
a X.509 certificate. This certificate MUST contain the PNC's
Fully Qualified Domain Name in the 'SubjectAltName', establishing
the PNC as a host in the Service Provider's domain
o a PNC capable of propagating local-network profiles or
unauthenticated device profiles MUST support the use of the SIP
Identity header as defined in [RFC4474] for inclusion in profile
notifications
Each profile type serves a different purpose, and is provided under
different circumstances and thus presents slightly different
requirements for authentication and protection of communication.
local-network profile
The local-network profile is provided by the local network and
usually contains non-sensitive data that is shared among all
participants in a local network. However, the framework also
allows for the presentation of the user's AOR, if known, for
possible privileged user data. This may, or may not, result in
user-specific information.
The following requirements are presented:
* the PNC MUST authenticate the identity of the user (if set to
anything other than the default) for local-network profile
requests that result in user-specific profile data containing
sensitive information; for authentication, unless other
mechanisms are employed, SIP Digest is used. If the
authentication fails, the PNC MUST not include any user-
specific information in the local-network profile
* the PNC MAY NOT authenticate requests for the local-network
profile that do not result in any user-specific sensitive data
(irrespective of the value of the From field)
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* the PNC MUST include the SIP Identity header as defined in
[RFC4474] within profile notifications sent in response to
local-network profile enrollment, unless an integrity-protected
channel exists (for example, using S/MIME)
* a device receiving profile notifications for local-network
profiles MUST verify the SIP Identity header, unless
transmitted over a previously established authenticated,
integrity-protected channel. If the header verification fails,
the device MUST not use the provided profile and treat it as a
local-network profile enrollment failure and take measures such
as enrollment retries
device profile
The device profile is expected to contain data specific to the
device identity (AOR) being presented in the request. The
presented identity may be auto-generated (for example, based on
its hardware identity as allowed in section Section 5.1.1.2.1) or
obtained via configuration. This identity and associated
credentials have the following considerations:
* credentials can be provided via out-of-band mechanisms such as
pre-configuration or user interface
* credentials may not be present, but obtained via the initial
device profile, if allowed by the Service Provider
* device may use the user's AOR and associated credentials for
obtaining the device profile
If the AOR presented in device profile enrollment is known by the
PNC, the following requirements are presented:
* the PNC MUST authenticate the AOR presented for enrollment
using SIP Digest authentication, unless a previously
established mutually authenticated channel exists (for example,
using TLS). If the authentication fails, the PNC MUST not
provide the requested device-specific profile. In such a
scenario, the PNC MAY still provide a generic device profile
for minimal services (for example, emergency calls in a
telephony deployment, see [I-D.ietf-ecrit-phonebcp])
* if the profile data is provided in the enrollment notificaiton,
the PNC MUST transmit it over an integrity-protected,
confidential communications channel such as TLS
If the AOR presented in device profile enrollment is not known by
the PNC, the following requirements are presented:
* the PNC MUST not provide any sensitive information in the
profile data
* the device MUST transmit the request over an integrity-
protected SIP communications channel. If none exists, the
device MUST establish a TLS connection with the PNC and verify
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the PNC's certificate. If the PNC authentication fails or a
secure communications channel cannot be established, the device
MUST treat it as a device profile enrollment failure and take
measures such as retry enrollment
user profile
The user profile is expected to contain data specific to the user
identity (AOR) being presented in the request. This identity is
expected to be known in the network and associated with
credentials. Thus, the following requirements are presented:
* the device MUST transmit the request over an integrity-
protected SIP communications channel. If none exists, the
device MUST establish a TLS connection with the PNC and verify
the PNC's certificate. If the PNC authentication fails or a
secure communications channel cannot be established, the device
MUST treat this as a user profile enrollment failure and take
measures such as retry enrollment
* the PNC MUST authenticate the AOR presented for enrollment
using SIP Digest authentication, unless a previously
established mutually authenticated channel exists (for example,
using TLS). If the user authentication fails, the PNC MUST not
provide the requested user-specific information. It MAY
provide minimal profile information (such as connection to a
customer support webpage)
* if the profile data is provided in the enrollment notificaiton,
the PNC MUST transmit it over an integrity-protected,
confidential communications channel such as TLS
9.2. Profile Content Retrieval
This framework does not mandate specific profile delivery frameworks,
but presents security requirements for profile content retrieval
using content indirection. Given the nature of the profiles, the
requirements are as follows:
o devices and PCCs compliant with this framework MUST implement HTTP
Digest authentication as specified in [RFC2617]; this is used
whenever an authentication challenge is initiated using HTTP based
protocols specified for interoperability
o a PCC complying with this framework MUST implement HTTPS
[RFC2818]; this is used when there are no existing integrity-
protected communication channels
o a PCC complying with this framework MUST contain a X.509
certificate. This certificate MUST contain the PNC's Fully
Qualified Domain Name in the 'SubjectAltName', establishing the
PNC as a host in the Service Provider's domain
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The following general requirement applies to all profile types:
o a device MUST request profile content retrieval over an integrity
protected channel such as HTTPS. If one does not exist or cannot
be established, then the device MUST treat this as a profile
content retrieval failure and take measures such as profile
content retrieval retries or in the case of retry exhaustion, try
enrollment
The following profile-specific usage requirements are presented
local-network profile
* a PCC MUST challenge a profile content retrieval request if the
profile data contains user-specific information; this challenge
is against a user's AOR, known by the PCC and the device
* a PCC MAY challenge a profile content retrieval request even if
the profile data contains user-specific information; this
challenge is against a user's AOR, if provided
device profile
* a PCC MUST authenticate a profile content retrieval request if
the AOR presented is known. If the authentication fails, the
PCC MUST not provide device-specific information. In such a
scenario, the PCC MAY still provide a generic device profile
for minimal services (for example, emergency calls in a
telephony deployment, see [I-D.ietf-ecrit-phonebcp])
user profile
* a PCC MUST authenticate a profile content retrieval request.
If the user authentication fails, the PNC MUST not provide the
requested user-specific information. It MAY provide minimal
profile information (such as connection to a customer support
webpage)
9.3. Profile Change Operation
Changes to profiles will only be made by authorized entities and
requires mutual authentication. The following requirements are
presented:
o a PCC complying with this framework MUST contain a X.509
certificate. This certificate MUST contain the PNC's Fully
Qualified Domain Name in the 'SubjectAltName', establishing the
PNC as a host in the Service Provider's domain. This may be the
same, or different, from the certificate used for profile content
retrieval
o an entity that is allowed to make updates MUST contain a AOR that
is known to the network and the requirements for making changes
are the same as that for user profile content retrieval, with the
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authorized entity playing the role of a user
10. Acknowledgements
Many thanks to those who contributed and commented on the many
iterations of this document. Detailed comments were provided by the
following individuals: Jonathan Rosenberg from Cisco, Henning
Schulzrinne from Columbia University, Cullen Jennings from Cisco,
Rohan Mahy from Plantronics, Rich Schaaf from Pingtel, Volker Hilt
from Bell Labs, Adam Roach of Estacado Systems, Hisham Khartabil from
Telio, Henry Sinnreich from MCI, Martin Dolly from AT&T Labs, John
Elwell from Siemens, Elliot Eichen and Robert Liao from Verizon, Dale
Worley from Pingtel, Francois Audet from Nortel, Roni Even from
Polycom, Jason Fischl from Counterpath, Josh Littlefield from Cisco,
Nhut Nguyen from Samsung.
The editor would like to extend a special thanks to the experts who
contributed to the restructuring and revisions as proposed by the
SIPPING WG, specifically Keith Drage from Lucent (restructuring
proposal), Peter Blatherwick from Mitel (who also contributed to the
Overview and Introduction sections), Josh Littlefield from Cisco
(examples and diagram suggestions), Alvin Jiang of Engin, Martin
Dolly from AT&T, Jason Fischl from Counterpath, Donald Lukacs from
Telcordia and Eugene Nechamkin from Broadcom. Additionally, sincere
appreciation is extended to the chairs (Mary Barnes from Nortel and
Gonzalo Camarillo from Ericsson) and the Area Directors (Cullen
Jennings from Cisco and Jon Peterson and Cisco) for facilitating
discussions, and for reviews and contributions.
11. Change History
[[RFC Editor: Please remove this entire section upon publication as
an RFC.]]
11.1. Changes from draft-ietf-sipping-config-framework-10.txt
The following are the changes that have been incorporated into this
I-D, resulting from the design team discussions based on Working
Group feedback.
o Modified the "From" header of the local network profile to reflect
the user's AOR, if any; delegated the device identifier to a new
event header termed "device-id"; removed use for 'network-user'
within the local-network profile; if there are objections to this,
please educate us!
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o Added text to indicate DHCPv4 or DHCPv6 to accomodate IPv4 and
IPv6 environments
o Replaced generic 'Service Provider' with terms to better represent
scenarios
o Analyzed the current SHOULD v/s MUST requirements for the Profile
Framework and made modifications
o Referenced RFC4122 instead of OUTBOUND
o Simplified the introductory sections to better illustrate
potential deployment possibilities; indicated the minimum profile
supported to be 'device'
o Revamped the security considerations sections
11.2. Changes from draft-ietf-sipping-config-framework-09.txt
Following the ad-hoc SIPPING WG discussions at IETF#67 and as per the
email from Gonzalo Camarillo dated 12/07/2006, Sumanth was appointed
as the new editor. This sub-section highlights the changes made by
the editor (as per expert recommendations from the SIPPING WG folks
interested in this effort) and the author.
Changes incorporated by the editor:
o Document was restructured based on a) Keith's recommendations in
the email dated 11/09/2006 and responses (Peter, Sumanth, Josh) b)
subsequent discussions by the ad-hoc group consisting of the
editor, the author, expert contributors (Peter Blatherwick, Josh
Littlefield, Alvin Jiang, Jason Fischl, Martin Dolly, Cullen
Jennings) and the co-chairs . Further changes follow.
o Use cases were made high-level with detailed examples added later
on
o Several sections were modified as part of the restructuring (for
example, Overview, Introduction, Framework Requirements, Security
Sections)
o General editorial updates were made
Changes incorporated by the author:
o Incorporated numerous edits and corrections from CableLabs review.
o Used better ascii art picture of overview from Josh Littlefield
o Fixed the normative text for network-user so that it is now
consistant: MAY provide for device profile, MUST provide for
local-network profile.
11.3. Changes from draft-ietf-sipping-config-framework-08.txt
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The Request URI for profile-type=localnet now SHOULD not have a
user part to make routing easier. The From field SHOULD now
contain the device id so that device tracking can still be done.
Described the concept of profile-type as a filter and added
normative text requiring 404 for profile types not provided.
Moved "application" profile type to
draft-ietf-sipping-xcap-config-01. The "application" value for
the profile-type parameter will also be used as a requirement that
XCAP be supported.
Fixed text on certificate validation.
Added new HTTP header: Event to IANA section and clean up the IANA
section.
Added diagram for Service Provider use case schenario.
Added clarification for HTTP Event header.
Added clarification of subscriber handling of NOTIFY with no body.
11.4. Changes from draft-ietf-sipping-config-framework-07.txt
Made XCAP informative reference. Removed "document" and "auid"
event header parameters, and Usage of XCAP section to be put in
separate supplementary draft.
Fixed ABNF for device-id to be addr-spec only (not name-addr) and
to be quoted as well.
Synchronized with XCAP path terminology. Removed XCAP path
definition as it is already defined in XCAP.
User agent instance ID is now defined in output (not GRUU).
Clarified the rational for the device-id parameter.
Added text to suggest URIs for To and From fields.
Clarified use of device-id parameter.
Allow the use of the auid and document parameters per request by
the OMA.
11.5. Changes from draft-ietf-sipping-config-framework-06.txt
Restructured the introduction and overview section to be more
consistent with other Internet-Drafts.
Added additional clarification for the Digest Authentication and
Certificate based authentication cases in the security section.
Added two use case scenarios with cross referencing to better
illustrate how the framework works. Added better cross
referencing in the overview section to help readers find where
concepts and functionality is defined in the document.
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
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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!
11.6. 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.
11.7. Changes from draft-ietf-sipping-config-framework-04.txt
Clarified usage of instance-id
Specify which event header parameters are mandatory or optional
and in which messages.
Included complete list of event header parameters in parameter
overview and IANA sections.
Removed TFTP reference as protocol for profile transport.
Added examples for discovery.
Added ABNF for all event header parameters.
Changed profile-name parameter back to profile-type. This was
changed to profile-name in 02 when the parameter could contain
either a token or a path. Now that the path is contained in the
separate parameter: "document", profile-type make more sense as
the parameter name.
Fixed some statements that should have and should not have been
normative.
Added the ability for the user agent to request that the default
user associated with the device be set/changed using the
"device-id" parameter.
A bunch of editorial nits and fixes.
11.8. 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
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package (i.e. simple-xcap-diff now defines a content type not a
package). Added an additional profile type: "application". Added
document and app-id Event header parameters in support of the
application profile. Define a loose high level data model or
relationship between the four profile types. Tried to edit and fix
the confusing and ambiguous sections related to URI formation and
discovery for the different profile types. Better describe the
importance of uniqueness for the instance id which is used in the
user part of the device URI.
11.9. 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.
11.10. 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.
11.11. Changes from draft-ietf-sipping-config-framework-00.txt
This version of the document was entirely restructured and re-written
from the previous version as it had been micro edited too much.
All of the aspects of defining the event package are now organized in
one section and is believed to be complete and up to date with
[RFC3265].
The URI used to subscribe to the event package is now either the user
or device address or record.
The user agent information (vendor, model, MAC and serial number) are
now provided as event header parameters.
Added a mechanism to force profile changes to be make effective by
the user agent in a specified maximum period of time.
Changed the name of the event package from sip-config to ua-profile
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Three high level security approaches are now specified.
11.12. Changes from draft-petrie-sipping-config-framework-00.txt
Changed name to reflect SIPPING work group item
Synchronized with changes to SIP DHCP [RFC3361], SIP [RFC3261] and
[RFC3263], SIP Events [RFC3265] and content indirection [RFC4483]
Moved the device identity parameters from the From field parameters
to user-agent header parameters.
Many thanks to Rich Schaaf of Pingtel, Cullen Jennings of Cisco and
Adam Roach of Estacado Systems for the great comments and input.
11.13. Changes from draft-petrie-sip-config-framework-01.txt
Changed the name as this belongs in the SIPPING work group.
Minor edits
11.14. Changes from draft-petrie-sip-config-framework-00.txt
Split the enrollment into a single SUBSCRIBE dialog for each profile.
The 00 draft sent a single SUBSCRIBE listing all of the desired.
These have been split so that each enrollment can be routed
differently. As there is a concept of device specific and user
specific profiles, these may also be managed on separate servers.
For instance in a nomadic situation the device might get its profile
data from a local server which knows the LAN specific profile data.
At the same time the user specific profiles might come from the
user's home environment profile delivery server.
Removed the Config-Expires header as it is largely superfluous with
the SUBSCRIBE Expires header.
Eliminated some of the complexity in the discovery mechanism.
Suggest caching information discovered about a profile delivery
server to avoid an avalanche problem when a whole building full of
devices powers up.
Added the user-profile From header field parameter so that the device
can request a user specific profile for a user that is different from
the device's default user.
12. References
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12.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A., and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
[RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000.
[RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston,
A., Peterson, J., Sparks, R., Handley, M., and E.
Schooler, "SIP: Session Initiation Protocol", RFC 3261,
June 2002.
[RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation
Protocol (SIP): Locating SIP Servers", RFC 3263,
June 2002.
[RFC3265] Roach, A., "Session Initiation Protocol (SIP)-Specific
Event Notification", RFC 3265, June 2002.
[RFC3268] Chown, P., "Advanced Encryption Standard (AES)
Ciphersuites for Transport Layer Security (TLS)",
RFC 3268, June 2002.
[RFC3315] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C.,
and M. Carney, "Dynamic Host Configuration Protocol for
IPv6 (DHCPv6)", RFC 3315, July 2003.
[RFC3319] Schulzrinne, H. and B. Volz, "Dynamic Host Configuration
Protocol (DHCPv6) Options for Session Initiation Protocol
(SIP) Servers", RFC 3319, July 2003.
[RFC3361] Schulzrinne, H., "Dynamic Host Configuration Protocol
(DHCP-for-IPv4) Option for Session Initiation Protocol
(SIP) Servers", RFC 3361, August 2002.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122,
July 2005.
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[RFC4474] Peterson, J. and C. Jennings, "Enhancements for
Authenticated Identity Management in the Session
Initiation Protocol (SIP)", RFC 4474, August 2006.
[RFC4483] Burger, E., "A Mechanism for Content Indirection in
Session Initiation Protocol (SIP) Messages", RFC 4483,
May 2006.
12.2. Informative References
[I-D.ietf-ecrit-phonebcp]
Rosen, B. and J. Polk, "Best Current Practice for
Communications Services in support of Emergency Calling",
draft-ietf-ecrit-phonebcp-00 (work in progress),
October 2006.
[I-D.ietf-simple-xcap]
Rosenberg, J., "The Extensible Markup Language (XML)
Configuration Access Protocol (XCAP)",
draft-ietf-simple-xcap-12 (work in progress),
October 2006.
[I-D.ietf-simple-xcap-diff]
Rosenberg, J., "An Extensible Markup Language (XML)
Document Format for Indicating A Change in XML
Configuration Access Protocol (XCAP) Resources",
draft-ietf-simple-xcap-diff-04 (work in progress),
October 2006.
[RFC0959] Postel, J. and J. Reynolds, "File Transfer Protocol",
STD 9, RFC 959, October 1985.
[RFC2131] Droms, R., "Dynamic Host Configuration Protocol",
RFC 2131, March 1997.
[RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
[RFC4510] Zeilenga, K., "Lightweight Directory Access Protocol
(LDAP): Technical Specification Road Map", RFC 4510,
June 2006.
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Authors' Addresses
Daniel Petrie
SIPez LLC.
34 Robbins Rd
Arlington, MA 02476
USA
Email: dan.ietf AT SIPez DOT com
URI: http://www.SIPez.com/
Sumanth Channabasappa (Editor)
CableLabs
858 Coal Creek Circle
Louisville, Co 80027
USA
Email: sumanth@cablelabs.com
URI: http://www.cablelabs.com/
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Full Copyright Statement
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contained in BCP 78, and except as set forth therein, the authors
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