SIPPING D. Petrie Internet-Draft SIPez LLC. Intended status: Standards Track S. Channabasappa, Ed. Expires:September 4,November 2, 2007 CableLabsMarch 3, 2007A Framework for Session Initiation Protocol User Agent Profile Deliverydraft-ietf-sipping-config-framework-11draft-ietf-sipping-config-framework-12 Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire onSeptember 4,November 2, 2007. Copyright Notice Copyright (C) The IETF Trust (2007). Abstract This documentdefinesspecifies 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 this framework, a new SIP event package is defined for notification of profile changes. The framework providesfor multipleminimal data retrievaloptions, without requiring or defining retrieval protocols.options to ensure interoperability. The framework does not include specification of the profile data within its scope. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . .45 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . .45 3. Executive Summary . . . . . . . . . . . . . . . . . . . . . . 6 4. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .5 3.1.7 4.1. Reference Model . . . . . . . . . . . . . . . . . . . . .5 3.2.7 4.2. Data Model and Profile Types . . . . . . . . . . . . . .9 3.3.10 4.3. ProfileLife Cycle . .Delivery Stages . . . . . . . . . . . . . . . . .9 4.10 5. Use Cases . . . . . . . . . . . . . . . . . . . . . . . . . .10 4.1.11 5.1. Simple Deployment Scenario . . . . . . . . . . . . . . .10 4.2.11 5.2. Devices supporting multiple users from different Service Providers . . . . . . . . . . . . . . . . . . . . 125.6. Profile Delivery Framework . . . . . . . . . . . . . . . . . .14 5.1.15 6.1. ProfileEnrollment . .Delivery Stages . . . . . . . . . . . . . . . . .17 5.1.1. Creation of15 6.1.1. Profile EnrollmentSubscription. . . . . . . . .17 5.1.2. Profile Enrollment Request Transmission .. . . . . .24 5.1.3. Profile Enrollment Notification. . . 16 6.1.2. Content Retrieval . . . . . . . .24 5.2. Profile Content Retrieval. . . . . . . . . . 18 6.1.3. Change Notification . . . . . .25 5.3. Profile Change Operation. . . . . . . . . . . 18 6.1.4. Enrollment Data and Caching . . . . .25 5.4. Profile Change Notification. . . . . . . . 19 6.1.5. User Profile Type . . . . . . .25 5.5. Additional Considerations. . . . . . . . . . . 22 6.2. Securing Profile Delivery . . . . .25 5.5.1. Manual retrieval of the Device Profile. . . . . . . .26 5.5.2. Device Types. . . 22 6.2.1. General Requirements . . . . . . . . . . . . . . . . . 23 6.2.2. Implementation Requirements .26 5.5.3. Profile Data. . . . . . . . . . . . 23 6.2.3. Identities and Credentials . . . . . . . . .27 5.5.4. Profile Data Frameworks. . . . . 24 6.2.4. Securing Profile Enrollment . . . . . . . . . .27 5.5.5. Additional Profile Types. . . 25 6.2.5. Securing Content Retrieval . . . . . . . . . . . .28 5.5.6. Deployment considerations. . 28 6.2.6. Securing Change Notification . . . . . . . . . . . .28 6. Event Package Definition. 29 6.3. Additional Considerations . . . . . . . . . . . . . . . . 29 6.3.1. Profile Enrollment Request Attempt . .28 6.1. Event Package Name. . . . . . . . 29 6.3.2. Device Types . . . . . . . . . . .29 6.2. Event Package Parameters. . . . . . . . . . 33 6.3.3. Profile Data . . . . . .29 6.3. SUBSCRIBE Bodies. . . . . . . . . . . . . . . 33 6.3.4. Profile Data Frameworks . . . . .32 6.4. Subscription Duration. . . . . . . . . . 34 6.3.5. Additional Profile Types . . . . . . . .33 6.5. NOTIFY Bodies. . . . . . . 34 6.3.6. Deployment considerations . . . . . . . . . . . . . . 35 7. Event Package Definition .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 7.1. Event Package Name . . . . . . .35 6.9. Handling of Forked Requests. . . . . . . . . . . . 36 7.2. Event Package Parameters . . .35 6.10. Rate of Notifications. . . . . . . . . . . . . 36 7.3. SUBSCRIBE Bodies . . . . .35 6.11. State Agents. . . . . . . . . . . . . . . 39 7.4. Subscription Duration . . . . . . .35 7. Examples. . . . . . . . . . . 39 7.5. NOTIFY Bodies . . . . . . . . . . . . . . . .35 7.1.. . . . . . 40 7.6. Notifier Processing of SUBSCRIBE Requests . . . . . . . . 40 7.7. Notifier Generation of NOTIFY Requests . . . . . . . . . 41 7.8. Subscriber Processing of NOTIFY Requests . . . . . . . . 41 7.9. Handling of Forked Requests . . . . . . . . . . . . . . . 42 7.10. Rate of Notifications . . . . . . . . . . . . . . . . . . 42 7.11. State Agents . . . . . . . . . . . . . . . . . . . . . . 42 8. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 8.1. Example 1: Device requesting profile . . . . . . . . . .36 7.2.42 8.2. Example 2: Device obtaining change notification . . . . .39 8.45 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . .43 8.1.49 9.1. SIP Event Package . . . . . . . . . . . . . . . . . . . .43 8.2. New HTTP Event Header49 9.2. Registry of SIP configuration profile types . . . . . . . 49 10. Security Considerations . . . . . . . . . . .43 9. Security Considerations. . . . . . . . 50 10.1. Local-network profile . . . . . . . . . . .44 9.1. Profile Enrollment and Change Notification. . . . . . .47 9.2. Profile Content Retrieval52 10.2. Device profile . . . . . . . . . . . . . . . . .49 9.3. Profile Change Operation. . . . 53 10.3. User profile . . . . . . . . . . . .50 10.. . . . . . . . . . 54 11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . .51 11.55 12. Change History . . . . . . . . . . . . . . . . . . . . . . . .51 11.1.55 12.1. Changes from draft-ietf-sipping-config-framework-11.txt . . . . . . . 56 12.2. Changes from draft-ietf-sipping-config-framework-10.txt . . . . . . .51 11.2.56 12.3. Changes from draft-ietf-sipping-config-framework-09.txt . . . . . . .52 11.3.56 12.4. Changes from draft-ietf-sipping-config-framework-08.txt . . . . . . .52 11.4.57 12.5. Changes from draft-ietf-sipping-config-framework-07.txt . . . . . . .53 11.5.57 12.6. Changes from draft-ietf-sipping-config-framework-06.txt . . . . . . .53 11.6.58 12.7. Changes from draft-ietf-sipping-config-framework-05.txt . . . . . . .54 11.7.58 12.8. Changes from draft-ietf-sipping-config-framework-04.txt . . . . . . .54 11.8.59 12.9. Changes from draft-ietf-sipping-config-framework-03.txt . . . . . . .54 11.9.59 12.10. Changes from draft-ietf-sipping-config-framework-02.txt . . . . . . .55 11.10.59 12.11. Changes from draft-ietf-sipping-config-framework-01.txt . . . . . . .55 11.11.59 12.12. Changes from draft-ietf-sipping-config-framework-00.txt . . . . . . .55 11.12.60 12.13. Changes from draft-petrie-sipping-config-framework-00.txt . . . . . .56 11.13.60 12.14. Changes from draft-petrie-sip-config-framework-01.txt . .56 11.14.60 12.15. Changes from draft-petrie-sip-config-framework-00.txt . .56 12.61 13. References . . . . . . . . . . . . . . . . . . . . . . . . . .57 12.1.61 13.1. Normative References . . . . . . . . . . . . . . . . . .57 12.2.61 13.2. Informative References . . . . . . . . . . . . . . . . .5862 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . .5863 Intellectual Property and Copyright Statements . . . . . . . . . .6064 1. Introduction SIP User Agents require configuration data to function properly. Examples include local 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 addressesmodifications to profiles and the correspondingchange notificationsto the SIP User Agents using a new event package.when profiles change. However, the framework does not define the content or format of the actual profile data, leaving that to future standardization activities. This document is organized as follows. Section 3 provides a brief executive summary of the framework operation. Section 4 provides a high-level overview of the abstract components, profiles, and profile delivery stages. Section 5 provides some motivating use cases. Section 6 provides details of the framework operation and requirements. Section 7 provides a concise event package definition. Section 8 follows with illustrative examples of the framework in use. 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 givendevicedevice. Local Network Provider: the entity that controls the local network to which a given device isconnectedconnected. 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,(e.g., user, device, local network or other). Profile Type: a particular category of Profile data(for example,(e.g., 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 overviewExecutive Summary The SIP UA Profile Delivery Framework uses a combination ofthe configuration framework. It introduces the reference modelSIP event messages (SUBSCRIBE andexplains key conceptsNOTIFY; [RFC3265]) and traditional file retrieval protocols, such asthe Profile Life CycleHTTP [RFC2616], to discover, monitor, andthe Profile Types. It is meantretrieve configuration profiles. The framework defines three types of profiles (local-network, device, and user) in order toserve as a reference section for the document, rather than providing a specific logical flowseparate aspects ofmaterial, as itthe configuration which may benecessary to revisit these sectionsindependently managed by different administrative domains. The initial SUBSCRIBE for each profile allows the UA to describe itself (both its implementation and its identity), while requesting access to acomplete understandingprofile by type, without prior knowledge ofthis document. The detailed framework forthe profiledelivery, presented in Section 5, is based onname or location. Discovery mechanisms are specified to help theconcepts introduced in this section. 3.1. Reference ModelUA form the SUBSCRIBE request URI. Thedesign ofSIP UAS handling these subscriptions is theframework wasProfile Delivery Server (PDS). When theresult ofPDS accepts acareful analysissubscription, it sends a NOTIFY toidentifytheconfiguration needs of adevice. The initial NOTIFY from the PDS for each profile may contain profile data or a reference to the location of the profile, to be retrieved using HTTP or similar file transfer mechanisms. By maintaining a subscription to each profile, the UA will receive additional NOTIFY messages if the profile is later changed. These may contain a new profile, a reference to a new profile, or a description of profile changes, depending on the Content-Type [RFC3261] in use by the subscription. The framework describes the mechanisms for obtaining three different profile types, but does not describe the data model they utilize (the data model is out of scope for this specification). 4. Overview This section provides an overview of the configuration framework. It introduces the reference model and explains the Profile Delivery Stages 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 6, is based on the concepts introduced in this section. 4.1. 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, theThe 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. Theset of interactions between these entities is referred to as the Profile Life Cycle. Thisreference model is illustrated inthe diagram below.Figure 1. +-------------------------+ +--------+Interactions| Profile Delivery Server | | Device |<==========================>| +---+ +---+ | +--------+(Profile Life Cycle)| |PNC| |PCC| | | +---+ +---+ | +-------------------------+ PNC = Profile Notification Component PCC = Profile Content Component Figure 1: Framework Reference Model The PDS is subdivided into two logical components: o Profile Notification Component (PNC), responsible for enrolling devicesin Profile event subscriptionsfor profiles and providingProfileprofile 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 sakeThe preceding framework reference model can be applied in a variety ofsimplicity, twodeployments scenarios. Two deployment scenarios representingeither enddifferent ends of theSIP deploymentcomplexity 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. TheProvider propogatesprovider propagates 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 inthe following diagram.Figure 2. -------------- / Local-network, \ | Device & Service | \ Provider / ---------------- | | -------- | Device | -------- | | ---- |User| ---- Figure 2: Simple System Level ModelThere are also deployments where the device canIn more complex deployments, devices connect via a local network that is not controlled by the SIP Service Provider,for example,such as devices that connect via available public WiFi hotspots. In such cases,Local Network Providerslocal network providers may wish to provide local network information such as bandwidth constraints to the devices. Devices may also be controlled byDevice Providersdevice providers that are independent of the SIPService Providerservice provider who provides user services,for example,such as 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 inthe following diagram.Figure 3 . -------- / 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 ------ ------ Figure 3: General System Level Model As illustrated, the simplest deployments present a single profile source whereas others may present multiple profile sources. Tobe effective, a configuration framework needs to address various deployment scenarios. Toaddress a vast majority ofdeploymentsdeployments, this framework specifies three distinct profiles, each of which can be obtained from a different provider, and set of a profilelife cycledelivery stages that are common to any profile type. The understanding is that deployments in general will support the defined profile types. However, the framework allows for flexibility in specialized cases.ThePDSs and devicesare required to supportwill implement all the three profiletypes, unlesstypes. Unless configuredotherwise (atotherwise, aminimum they need to support thedeviceprofile). The deployments are requiredwill try tosupport the device profile, and user profiles for known users. Inobtain all thepresence of multiple profiles, athree profile types. A retrieval order is specified for thedevices.profile. Additional profiles may also be specified outside the scope of this document, but are expected to follow the same profilelife cycle. 3.2.delivery stages. 4.2. 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:cContainsContains 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 ServiceProvider providing services. 3.3.Provider. 4.3. ProfileLife Cycle Automated profile deliveryDelivery Stages The framework specified in this document requiresproactive behavior on the part ofadevice.device to explicitly request profiles. It also requires one or more PDSs which provide the profile data. Theset of communicationsprocesses thatresults 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 thelead a deviceenrolls 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 usedtoretrieve the profile. Additionally, the profile life cycle allows for profile change operations by authorized entities. If aobtain profilechange operation is successful, it resultsdata, and any subsequent changes, can be explained inprofile change notifications to all enrolled devices. The specific functional steps are as follows:three stages, termed the Profile Delivery Stages. 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 or5. Use Cases This section provides adevice - pushes a profile change to the PDS. 4. Use Cases This section provides a small -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 Section9. 4.1.6 and Section 10. 5.1. Simple Deployment Scenario Description: Consider a deployment scenario(for example,(e.g., a small private enterprise) where a single entity enables the local network, manages deployed devices and provides SIP services. The devicesnever connect outsideonly attach to the localnetworknetwork, and areeachpre-configured with a single user. The following assumptions apply: o The device profile data contains all the information necessary for the device to participate in the local network and obtainservicesservices. o The device is pre-configured to only request the deviceprofileprofile. o The enrollment notification contains the profile data (profile content retrieval is notrequired) The following diagramrequired). o There are no proxies in the network. Figure 4 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 | | | | | Figure 4: Use Case 1 The following is an explanation of the interactions inthe diagram.Figure 4. (A) Upon initialization, the device obtains IP configuration parameters usingDHCPDHCP. (B) The device performs Profile Enrollment for the device profile; the device profile data is contained in the enrollmentnotificationnotification. (C) Due to a modification of the device profile, a Profile Change Notification is sent across to the device, along with the modifiedprofile 4.2.profile. 5.2. Devices supporting multiple users from different Service Providers Description: Consider a single device(for example,(e.g., Kiosk at an airport) that allows for multiple users to obtain services from a list ofpre-configuredpre- 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 userBB. o Profile enrollment always results in content indirection information requiring profile contentretrieval The following diagramretrieval. o Communication between the device and the PDSs is facilitated by SIP proxies. Figure 4 illustrates the use case and highlights the communications relevant to the framework specified in this document. 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>> | Figure 5: Use Case 2 The following is an explanation of the interactions inthe diagram.Figure 5. (A) Upon initialization, the device obtains IP configuration parameters using DHCP. This also provides the local domain information to help with local-network profileenrollmentenrollment. (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 availablebandwidth)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-existingsubscriptionservice relationship 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 apre-existing subscriptionservice relationship 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.5.6. Profile Delivery Framework This sectiondetailspresents theframework requirements.profile delivery framework, the subject of this document. The section starts by explaining the framework via the profile delivery stages. It then explains how the framework secures the profile data propagation. It ends with considerations such as back-off and retry mechanisms and profile data. 6.1. ProfileLife Cycle (introduced in Section 3),Delivery Stages There are three profile delivery stages: profile enrollment, content retrieval and change notification. The first step isexamined in further detail,profile enrollment and serves two purposes. It allows a device to enroll withrequirements that applya PDS. It also allows the PDS to receive thedevicerequest, authenticate if necessary, authorize and enroll thePDS. Unless explicitly enhanced or indicated by an implementing specification,device. If the deviceandenrolls successfully, the PDSMUST followtransmits a notification to theProfile Life Cycle requirements stated in this section for all supporteddevice. This notification contains either the requested profiletypes. A high-level representation ofdata, or content indirection information indicating theframework is shown inPCC that can provide thefollowing state diagram. Eachprofile data. Usage of content indirection is optional. When employed, the retrieval of thespecifiedprofiletypesdata isretrieved individually,described by the stage termed content retrieval. Based on the enrollment request, the PDS may enroll the device for a period in time during which the device is notified of any profile changes. This stage is termed change notification. The stages apply to any profile specified by this framework. Devices and PDSs MUST comply with the requirements as specifiedorder (see below), until all needed Profiles have been received. --------------- / Device \ \ Initialization/ --------------- | | Completes IP initialization; | Initializes SIP stack | V -------------- ________\ / All profiles?\ | / \ retrieved? / | -------------- | | | | NO; attempt | | Profile Request | |in this section. The details and the requirements are specifiedorder | | | V | ------------ ___________/below. 6.1.1. Profile\ \ Life Cycle / ------------ Framework state diagram TheEnrollment ProfileLife Cycle, for each profile,enrollment isillustrated inthediagram below. ------------- { Device enrolls / Profile \ ...{process by means of which a device requests, andobtains \ Enrollment / {receives, profile data. Each profile type specified in this document requires an independent enrollment------------- { notification | | SUCCESS | | ...PDS... V ...DEVICE... __________________________________ | | | | Active | Subscription? | (i.e, notrequest. However, a particular PDS can support enrollment for one| time fetch) | | | | YES | | | V V -------------- / Profile Change \ __________________\ Content \ Notification / / Indirection? -------------- | ^ | | | YES | SUCCESS | | V -------------- ---------------- / Profile Change\ /or more profile types. ProfileContent \ \ Operation / \ Retrieval / --------------- ----------------- Theenrollment consists of the following operations, in the specified order. Enrollment request transmission ProfileLife Cycleenrollment is initiated when the device transmits an enrollment requestforusing aspecific profile. If thisSIP SUBSCRIBE request [RFC3265] for the event package specified in Section 7.2. The profile being requested isaccepted, it resultsindicated using the 'profile-type' parameter. The device MUST transmit the SIP SUBSCRIBE message in accordance with RFC 3263 [RFC3263]. The device needs certain data to create an enrollmentnotification that containsrequest. This includes the profile provider's domain name, identities and credentials. Such data can be "configured" during device manufacturing, by the user prior to network connectivity, or via profilecontent indirection information. Unlessdata retrieval. It can also be "discovered" using theenrollment request indicatesprocedures specified by this framework. The "discovered" data can be retained across device resets (but not across factory resets) and such data is refered to as "cached". Thus, data can be cached, configured or discovered. The following rules apply. * If the device is configured with aone-time profile request,specific domain name (for the local network provider or device provider), italso resultsMUST NOT attempt re-discovery of the domain name. * The device MUST only use data associated with the provider's domain in an enrollmentfor profile change notifications. Ifrequest. As an example, when theprofiledevice ismodified at any pointrequesting a local-network profile intime,theprofile change notification is transmitted todomain 'example.net', it cannot present a user AoR associated with thedevice. Notifications duelocal domain 'example.com'. * The device SHOULD adhere toprofile enrollment or change operation may result in content indirection in which casethe following order of data usage: cached, configured, and discovered. An exception is when the deviceuses profile content retrievalis explicitly configured to use a different order. Upon failure to obtain the profiledata. The Profile Life Cycle isusing any methods specified in this framework, thesamedevice MAY provide a user interface to allow foralluser intervention. This can result in temporary, one-time data to bootstrap theprofile types, but there are different requirements in each step based on the profile types. This framework defines three profile typesdevice. Such temporary data is not considered to be "configured" andan order that MUSTis not expected to befollowed bycached across resets. The configuration obtained using such data MAY provide the configuration data required for the device to continue functioning normally. Devices attempting enrollment MUST comply with the SIP-specific event notification specified inrequesting them (when it retrieves two or more of[RFC3265], thedefined profile types), as follows: o local-network o device o user The sub-sections that follow specifyevent package requirements specified in Section 7.2, and theProfile Life Cycle details, with specificsecurity requirementsbased on each profile type. 5.1. Profilespecified in Section 6.2. EnrollmentThe first step to obtaining a profile isrequest admittance A PDSEnrollment. This is initiated by the device and involves: o creatingor aprofile enrollment subscription o transmittingSIP infrastructure element (such as aprofile enrollment request o receivingSIP proxy) will receive aprofiletransmitted enrollmentnotification The processes are interlinked and retries encompass all three phases. For example, ifrequest. If a SIP infrastructure element receives theenrollment request does not resultrequest, it will relay it to the authoritative proxy for the domain indicated ina profile enrollment notification,thedeviceRequest-URI. The authoritative proxy is required toretry alternateexamine the request (e.g., event package) and transmit it to a PDS capable of addressing the profile enrollmentsubscription creation options. Only when allrequest. A PDS receiving the enrollmentsubscription creation options are exhausted doesrequest SHOULD respond to thedevice assumerequest, or proxy it to a PDS that can respond. An exception is when theprofile enrollment has failed.a policy prevents a response (e.g., recognition of a DoS attack, an invalid device, etc.). Theprocesses themselves are illustratedPDS then verifies the identity presented in thefollowing sub-sections. 5.1.1. Creation of Enrollment Subscription Each profile type requires its own subscriptionrequest andbased onperforms any necessary authentication. Once authentication is successful, theentity requesting it, presents certain unique requirements (for example,PDS MAY admit or reject thedevice identifier is provided forenrollment request, based on applicable authorization policies. A PDS admitting thedevice profile type whereenrollment request indicates it via a 2xx-class response, asthe user identifier is providedspecified in [RFC3265]. Refer to Section 7.6 and Section 6.2 for more information on subscription request handling and security requirements, respectively. Enrollment request acceptance A PDS that admits theuser profile type). Further,enrollment request verifies applicable policies, identifies the requested profiletypes are aimed at different PDSsdata andhence are identified differently (for example, the local-network is identified by the local domain name where as the Service Provider is identified based onprepares a SIP notification to theService Provider's domain name). Some of this informationdevice. Such a notification canbe obtained in multiple ways (such as local domaineither contain the profile data or contain content indirection information thatcan be configured statically or dynamically) andresults in the devicemay have to try different information sources to obtainperforming profile content retrieval. The PDS then transmits therequired information (for example, dynamic configuration can override statically configured information). Based on these considerations,prepared SIP notification. When theframework defines different rules for obtainingdevice successfully receives andpresentingaccepts theinformation for eachSIP notification, profiletype. Additionally, when more than one information sourceenrollment ispossible for the information,complete. When itis presented as well. This is highlighted in the following sub-sections. 5.1.1.1. SIP SUBSCRIBE forreceives theLocal-Network profile type Before attempting to create aSIPSUBSCRIBE requesting the local- network profile,notification indicating enrollment acceptance, the device MUSThave established local network connectivity. It MUST also have knowledge ofmake thelocal network domain either via static configuration or dynamic discovery via DHCPv4 ([RFC2131]) or DHCPv6 ([RFC3315]). The following requirements apply: onew profile effective within theuser part ofspecified timeframe, as described in Section 7.2. Once profile enrollment is successful, theRequest URIPDS MUSTNOT be provided. The host and port part ofconsider theRequest URI MUST be set todevice enrolled for theconcatenationspecific profile, for the duration of"sipuaconfig" andthelocal network domain o a user AOR, if knownsubscription. 6.1.2. Content Retrieval A successful profile enrollment leads to an initial SIP notification, and may result in subsequent change notifications. Each of these notifications can either contain profile data, or content indirection information. If it contains content indirection information, the deviceMUST be used to populate the "From" field, unless privacy requirements prohibit its use (thisisuseful if the user has privileges inrequired to retrieve thelocal network beyond those ofprofile data using thedefault user) o if a user AORspecified content retrieval protocols. This process isnot known,termed profile content retrieval. For information regarding theuser portioncontent of the"From" field MUST be setnotification body please refer to"anonymous"; the hostSection 7.5. Devices andport portion of the Request URIPDSs implementing this framework MUSTbe set to the concatenationimplement two content retrieval protocols: HTTP and HTTPS as specified in [RFC2616] and [RFC2818], respectively. Future enhancements or usage of"sipuaconfig"this framework may specify additional or alternative content retrieval protocols. For security requirements andthe local network domain o the "device-id" event header parameter MUST be setconsiderations please refer tothe 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-NetworkSection 6.2. 6.1.3. Change Notification ProfileSUBSCRIBE Request URI would look like: sip:sipuaconfig.airport.example.net The Event header would look like the following ifdata can change over time. Changes can be initiated by various entities (e.g., via thedevice decideddevice, back-office components and end-user web interfaces) and for various reasons (e.g., change in user preferences and modifications toprovide MAC%3a00DF1E004CD0@airport.example.net as the device identifier. (Alice may haveservices). When aprior 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-networkprofileSUBSCRIBE Request URI does not have a user part so that the URIisdistinct between the "local" and "device" URIs whenchanged thedomain isPDS MUST inform all thesamedevices currently enrolled for thetwo.specific profile. Thisprovidesprocess of informing ameansdevice ofroutingany changes to theappropriateprofile that it is currently enrolled for is termed change notification. The PDS provides change notification using a SIP notification (SIP NOTIFY message as specified indomains where they are distinct servers.[RFC3265]). TheFrom field is populated with the user AOR, if available. This allowsSIP notification may provide thelocal network provider to propagate user-specificchanges, a revised profiledata, if available. The "device-id" event header parameter is setor content indirection which contains a pointer to the revised data. When a deviceidentifier. Even though every device may get the same (or similar) Local-Network Profile, the uniqueness of the "device-id" event header providessuccessfully receives a profile change notification for animportant capability. Having unique From fields allows the management ofenrolled profile, it MUST act upon thelocal networkchanges prior totrack devices present inthenetwork 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 allowsexpiration of theService Provider managing a device'Expires' parameter. For NOTIFY content please refer toprovide device-specific configuration information.Section 7.5. 6.1.4. Enrollment Data and Caching Toenable this,enroll, theRequest URIdevice needs toidentify the device and the PDS domain within which itrequest enrollment. This isrecognizable. Accordingly, this Framework presents the followingdone via a SIP SUBSCRIBE message. The requirements for theformationcontents ofa Subscription Request URI to requestthe"device"SIP SUBSCRIBE are described in this section. The data required can be configured, cached or discovered - depending on the profiletype otype. If theuser portion ofdata is not configured, theRequest URIdevice MUSTbe set touse relevant cached data or proceed with data discovery. This section describes the requirements for creating aunique device Identifier oSIP SUBSCRIBE for enrollment, thehostcaching requirements andport portion of the Request URI MUSThow data can beset to the PDS domain The following sub-sections explain identification of - anddiscovered. 6.1.4.1. Local-Network Profile To request therequirements related to -local-network profile a device needs the local network domain name, a deviceIdentifieridentifier and optionally a user AoR with associated credentials (if one is configured). Since thePDS domain discovery. 5.1.1.2.1. Device Identifier Thedeviceprofile couldcan bespecific to each devicepotentially initialized in aSIP deployment (for example, vendor/model)different local-network each time, it SHOULD NOT cache the local network domain orsharedSIP subscription URIs acrossdevice types (for example, based on services and service tiers). Further,resets. An exception to this is when thesamedevicemight be provided different configuration profiles based on deployment models. Device Identifiers play a significant rolecan confirm that it is reinitialized inensuring delivery ofthecorrect profile and hence need to be unique within a PDS domain to supportsame network (using means outside the scope of this document). Thus, in most cases, thevarious deployment models. This Framework requires thatdeviceIdentifiers MUST be unique and persistent overneeds to discover thelifetime of a device. Device Identifier representations auto-generatedlocal network domain name. The device discovers this bydevices SHOULD be based on MAC address or UUID ([RFC4122]) based representations. Aestablishing IP connectivity in the local network. Once established, the devicemayMUST usealternate device identifiers (for example, SIP URIs)the local network domain obtainedvia pre-configuration or dynamic configuration (for example, device profile).using static configuration. Ifa MAC addressit isused,not configured, it MUST employ dynamic discovery using DHCPv4 ([RFC2132], Domain Name option) or DHCPv6 ([RFC4704]). Once thefollowing requirements apply: olocal network domain is obtained, the deviceidentifier MUST be formattedcreates the SIP SUBSCRIBE for enrollment as described below. o The device MUST NOT populate thecharacters "MAC:" followed by a twelve digit hexadecimal upper case representationuser part of theMAC address to form a proper URN ([RFC2141]).Request URI. TheMAC address representationdevice MUSTNOT include visual separators such as colons and whitespaces. The representation is denoted usingset thefollowing ABNF syntax mac-ident = MAC ":" 12UHEX MAC = %x4d.41.43 ; MAC in caps UHEX = DIGIT / %x41-46 ; uppercase A-F ohost and port of theMAC address MUST only be usedRequest URI torepresent 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,theUUID representation SHOULD be used If a UUID is used,concatenation of "_sipuaconfig" and thefollowing requirements MUST apply:local network domain/port. o If thesame approach to definingdevice has been configured with a useragent Instance IDAoR for the local network domain (verified as[RFC4122]explained in Section 6.2) it MUSTbe used o when the URN is used asuse it to populate theuser part of"From" field, unless explicity configured not to (due to privacy concerns, for example). If not, theURI, itdevice MUSTbe URL escaped The colon (":") is not a legal character (without being escaped) inset theuser part"From" field to a value ofan addr-spec ([RFC4122]). For example"anonymous@anonymous.invalid". o The device MUST include theinstance ID: urn:uuid:f81d4fae-7ced-11d0-a765-00a0c91e6bf6@example.com would be escaped to look+sip.instance parameter within the 'Contact' header, asfollowsspecified ina URI: sip:urn%3auuid%3af81d4fae-7ced-11d0-a765-00a0c91e6bf6@ example.com[I-D.ietf-sip-outbound]. TheABNF fordevice MUST ensure that theUUID representationvalue of this parameter isprovidedthe same as that included in[RFC4122] 5.1.1.2.2. PDS Domain Discovery A device needs to identifythePDS domain to formdevice profile enrollment request. For example, if thehostdevice requested andport part ofreceived theRequest URI. Ideally, this information should be obtainedlocal domain name viaa 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 hurdlesDHCP tospecifying a single method (for example, ifbe: airport.example.net, then the local-network Profile SUBSCRIBE Request URI would look like: sip:_sipuaconfig.airport.example.net The local-network profile SUBSCRIBE Request URI does not have adevice is always inuser part so that theSIP Service Provider's network one could use DHCP). To accommodate multiple deployment scenarios,URI is distinct between theframework specified in this document presents multiple approaches. Devices MUST follow"local" and "device" URIs when theprocedures specified below indomain is theorder presented, unless exceptions are made by device manufacturers or Device Providers who may provide an optionsame for theusertwo. This provides a means of routing tochoosetheorder (to suit specific deployment models, for example). 1. Service Provider pre-configurationappropriate PDS in domains where there are distinct servers. Thedevice MAY be pre-configuredFrom field is populated withinformation that can be utilized to identifythehost and port ofuser AoR, if available. This allows theRequest URI.local network provider to propagate user-specific profile data, if available. Theinformation can be provided - as examples - when"+sip.instance" parameter is set to the deviceis manufactured, by using Service Provider entities (flash card, SIM card) or via a Service Provider specific method (for example, informationidentifier ormethods that lead to self subscription). Ifspecifically, the SIP UA instance. Even though every deviceis specified to utilize this approach, it MUST attempt to do so before trying other methods. The details of how this is accomplished are beyondmay get thescopesame (or similar) local-network Profile, the uniqueness ofthis document. 2. IP Configuration If pre-configuration is notthe "+sip.instance" parameter provides anoption, or not available, IP configuration MUST be utilized to try and obtain information that can help with identificationimportant capability. Having unique From fields allows the management of thehost and port forlocal network to track devices present in theRequest URI.network and consequently also manage resources such as bandwidth allocation. 6.1.4.2. Device Profile Type Theframework definesdevice profile is intended for obtaining information from thefollowing methods within this procedure to accomplish this.deviceMUST followprovider managing themethods defined, indevice. To request theorder specified, i.e. ifdevice profile, thefirst option cannot be accomplished or results indevice needs afailure, then next method is tried. Failure ofunique device identifier, the device provider's domain name and optionally aspecific methoddevice AoR (if configured). The device AoR isindicated whenan AoR associated with the devicecannot successfully complete Profile Enrollment. 2a. DHCP optionforSIP server: Devicesobtaining device profiles. This is considered to be a special 'user AoR' for the device profile, and can be the same as a user AoR associated with the device. Once a provider is associated with a device, the device provider will not change frequently (an example of a change is the re-use of the same device while changing device providers). Thus, the device SHOULD cache the Subscription URI for the device profile upon successful enrollment, and use it upon reset. Exceptions include cases where the device identifier has changed (e.g., new network card with a new MAC address), device provider information has changed (e.g., user initiated change) or the device cannot obtain its profile using the Subscription URI. If it is not configured, then the device MUST use a cached, or discovered domain name. If the device does not have a configured or cached Subscription URI, then it can use the device AoR. If that is unavailable, it can use the configured device provider's domain to form the subscription URI. The following options are provided for device provider's domain discovery (used only when it is not configured with one). The device MUST use the results of each successful discovery process for one enrollment attempt, in the order specified below. o Option 1: 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 IPv6respectively), 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,respectively). The values are then used to populate the RequestURI would be constructed as sip:MAC%3aABC123EFD456@example.com 2b. Local IP Network Domain: - devicesURI. o Option 2: Devices that support DHCP MUST attempt to obtain the local IP network domain during the DHCPprocess, using DHCP option 15process (refer to [RFC2132] anduse these[RFC4704] ) and use this as the hostand port partportion of therequest URI using the technique specificed in [RFC3263] + For example, a MAC based devices identifier with a DHCP option 15 indicating local.example.com, theRequestURI would be constructed as sip:MAC%3aABC123EFD456@local.example.com - IfURI. o Option 3: Devices MUST use the localIPnetwork domain name (configured or discovered to retrieve the local-network profile), prefixing it with the label "_sipuaconfig". This isavailable (previous method), butthen used as theusagehost portion of thelocal IP Network domain results in a failure,Request URI. If the deviceMUST usehas to create a new Subscription URI (i.e., from a configured domain name, or if thelocal IP network domain, prefixing it usingcached URI is unusable) thelabel "sipuaconfig." + For example, a MAC basedfollowing requirements apply. o The deviceIdentifier with a DHCP option 15 indicating local.example.com,MUST set the Request URIwould be constructed as sip:MAC%3aABC123EFD456@sipuaconfig.local.example.com 3. Manualto the device AoR, if known. Ifpre-configuration and IP Configuration are not optionsit is unavailable orresult in failures,thedevice SHOULD provide a means forenrollment fails, theuser to present information that may help withdevice MUST use theretrieval process. Exceptions todevice identifier (specified later in thisrequirement MAY include devicessection) along withno user interface appropriate for such entry. This framework providesthefollowing alternatives which can be considered individuallydevice provider's domain name and port (configured ortogether, in any order. Device Provider PDS information: The user SHOULD be alloweddiscoverd) topresentform thehost and port information which can helpRequest URI. o If the device has been configured with a device AoR, then it MUST use it to populate thecreation of"From" field. If not, theSubscription URIdevice MUST set the "From" field tolocateaPDS capablevalue ofproviding the profile. Device Provider Configuration Server informationanonymous@<device provider's domain>. o Theuser MAY be alloweddevice MUST include the +sip.instance parameter within the 'Contact' header, as specified in [I-D.ietf-sip-outbound]. The device MUST use the same value as the one presented while requesting the local-network profile. When the device needs to presentinformation pertainingits device identifier it MUST use the UUID-based URN representation for the user portion of the Request-URI, as specified in [RFC4122]. The following requirements apply: o When the device has a non-alterable MAC address it SHOULD use version 1 UUID representation with the timestamp and clock sequence bits set to a value of '0'. This will allow for easy recognition, and uniqueness of MAC address based UUIDs. An exception is the case where the device supports independent device configurationserver that providesfor more than one SIP UA. An example would be multiple SIP UAs on the same platform. o If the deviceprofile, not usingcannot use aPDSnon-alterable MAC Address, it MUST use the same approach asdefineddefining a user agent Instance ID inthis framework. This framework specifies one such possible process[I-D.ietf-sip-outbound]. o When the URN is used as the user part of the Request URI, it MUST be URL escaped The colon (":") is not a legal character (without being escaped) inSection 5.5.1. 5.1.1.3. SIP SUBSCRIBEthe 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] 6.1.5. User Profile Type The user profile allowsthe responsiblea SIP Service Provider to provideuser-specificuser- specific configuration. This is based onthe user's identitya user AoR that isusuallyknowninby thenetwork (for example, associated with a subscription). Similar toPDS and statically or dynamically configured on theprofiles provideddevice (e.g., user entered or propagated as part of the device or other profile). Similar todevices,device profiles, the content and propagation of userProfilesprofiles maypartake differently,differ, based on deployment scenarios(for example,(e.g., users belonging to the samesubscription mightdomain may - ormightmay not - be provided the same profile).However, each user is uniquely identified in a SIP Service Provider's network using an Address Of Record (AOR). Devices implementing thisThis frameworkMUST use the user's AOR to populatedoes not specify any discovery mechanisms for this profile type. Unless configured, theRequest URI. AdeviceMAY obtain the user's AOR using various methods such as pre- configuration, viacannot, and MUST NOT, request thedevice profile or dynamically via auserInterface. 5.1.1.4. Caching of SIP Subscription URIs Creation of Subscription URIs is vital for successfulprofile. 6.2. Securing ProfileEnrollment. UnlikeDelivery This section further explains theuser Profile - Local-Network and device profiles are expected to be requested based on discovered information (for example, domain name discovered via DHCP). Theseprofiletypes have different goals and hence, caching ofdelivery stages. Specifically, it presents theSubscription URI should be carefully considered. The Local-Networkrequirements necessary to secure profiletypedelivery. It isaimed at obtaining information fromto be noted that future enhancements to thelocal network. The local network can change across device initializations (for example, user movesframework may specify additional or alternative behavior. Any such enhancements should be cryptographically equivalent to, or increase, thedevice from a home networkrequirements presented in this document. For security threats and considerations addressed by this section please refer toa workplace LAN). Thus, the device SHOULD NOT remember local-networkSection 10. 6.2.1. General Requirements Profile data retrieval starts with profilesubscription URIs across initializations.enrollment. The deviceSHOULD re-create the Subscription URI every timeforms a SIP subscription as specified in Section 6.1.4 and transmits itmovestoa new network or gets re-initialized. Exceptions may be cases wherethedevice can unambiguously determine changes toSIP entity resulting from thelocal network.procedures specified in [RFC3263]. Thedeviceentity to which it transmits the profiletypeenrollment isaimed at obtaining information fromtermed the 'next-hop SIPService 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 deviceentity'. It canonlybesure 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 withanew MAC address), Service Provider information has changed (for example, user initiates change)SIP proxy orthe 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 thataPDS may send 202 responses to SUBSCRIBE requestsPDS. This framework utilizes TLS ([RFC4346]) andNOTIFY responses to unknown devices (see'Server Identity' verification as specified in [RFC2818], Section6.6) with no profile data or URIs. Thus, successful Profile Notification3.1. The 'Server Identity' in this case is always theonly sure way to know thatdomain of theSubscription URInext-hop SIP entity. The verifier isvalid. 5.1.2. Profile Enrollment Request Transmissionthe device. Adevice requestingTLS session that results from aprofile type specified in this document - and issuccessfulin forming a Subscription URI - MUST enroll usingverification of theevent package defined, and as specified, in this framework (see Section 6) .next-hop SIP entity is termed a 'Server identity verified TLS session' or 'next-hop entity verified TLS session'. 6.2.2. Implementation Requirements The followingrequirements apply: oare the general implementation requirements. - A device MUSTcater to the Event Package requirementsimplement TLS ([RFC4346]) with support for Server Identity verification as specified inSection 6.2 (for example, indicate[RFC2818] - PDSs SHOULD contain X.509 certificates that can allow for PDS authentication using the procedures specified in [RFC2818]. Exceptions are PDSs that do not propagate sensitive profiletype being requesteddata (e.g., a local-network PDS that does not support sensitive profile data). - PDSs that are configured with X.509 certificates (as described above) MUST implement TLS [RFC4346] and support 'Server Identity' verification as specified by [RFC2818]. - PDSs that are configured with X.509 certificates (as described above) SHOULD implement SIP Identity as specified in [RFC4474]. When theprofile-type parameter) oSIP Identify header is included, thedevicePDS MUSTuseset theSubscription URI pertaining tohost portion of theprofile type being requested, as specifiedAoR inSection 5.1 The SIP infrastructure receiving such requeststhe 'From' header to the local network domain. It isexpectedtorelaybe noted that the requirement to implement TLS does not imply its usage in all cases. Please refer to the rest of this section for usage requirements. 6.2.3. Identities andprocess profile enrollment requests. WhenCredentials To enroll for aProfile Enrollment request is received byprofile, the device needs to provide an identity. This can be aPDS, it SHOULD acceptuser AoR (local-network andrespond to any profile requests. Exceptions are when Service Provider policy prevents suchuser profiles), aresponse (for example, requesting entity is unknown). Successful Profile Enrollment involves the following o Acceptance ofdevice AoR (device profile), theSUBSCRIBE request by a PDS (indicated viadevice identity (device profile), or a200 response) o Receipt offramework-specified identity (local-network profile). To be able to present aninitial Profile Notification within the timeoutsidentity, such asspecifieda user AoR, the device needs to be configured. This can be accomplished in[RFC3265]one of many ways: Pre-configuration A distributor of the deviceSHOULD follow suitable BackOffmay pre-configure the device with identities andRetry mechanisms ifassociated credentials. Identities refers to asuccessful 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, thedeviceretrieves the profile using Profile Content Retrieval. If the profile contents are provided, the following requirements hold good: oAoR (for use with the deviceMUST makeprofile) or a user AoR. Out-of-band methods A device or SIP service provider may provide thenew profiles effective withinend-user with hardware- or software-based devices that contain thespecified timeframe, as described in Section 6.2 oidentities and associated credentials. Examples include SIM cards and USB drives. End-user interface The end-user may be provided with user AoRs and credentials. The end-user can then configure the deviceSHOULD cache (i.e. store persistently) the contents of retrieved profiles, until overridden by subsequent Profile Change Notifications (this avoids situations where(using aPDS is unavailable, leaving the device withoutuser interface), or present when requiredconfiguration) Failure to receive the initial NOTIFY following(e.g., IM login screen). Using this framework When asuccessful enrollment MUST be treateddevice is initialized, even if it has no pre-configured information, it can request thesame as a failed enrollment.local-network and device profiles. In such ascenario,case the deviceMUST retry using alternate methods for creationprofile can provide three kinds of information: * Profile data that allows theenrollment subscription and transmit an enrollment request. If all the enrollment subscription creation have been exhausted,end-user to communicate with the deviceMUST treat it as a failureor SIP service provider. The provider can then use any applicable method (e.g., web portal) toobtainprovide theprofile and take appropriate measures. For NOTIFY content please refer to Section 6.5. 5.2. Profile Content Retrieval Upon successfuluser AoR. * ProfileEnrollment,data that redirects the devicecan retrieve the documents pertainingtothe requested profile directly or via the URI(s) provided in the NOTIFY requestan entity, such asspecified in Section 6.5. Profile Content Retrieval protocols and frameworks are out of scope for this specification. 5.3. Profile Change Operation Configuration Profilesthe PCC, that canchange over time. Modificationsprovide identity data. As an example, consider a device that has a X.509 certificate that can beinitiatedauthenticated byvarious entities (for example, viathedevice, 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 forPCC. In suchchanges 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,aPDS compliant with this framework MUST NOTIFY allcase, thedevices currently subscribedPCC can use HTTPS to provide theprofile under consideration. This process is termeduser AoR. * ProfileChange Notification. For NOTIFY content please referdata containing user identity toSection 6.5. 5.5. Additional Considerationsbe used. Thissection provides a special case for retrieval ofcan be used in cases where the deviceprofile and highlights considerations and requirements on external entities such as Profile Data Frameworks. 5.5.1. Manual retrieval ofis initialized for theDevice Profile Atfirst time, or after aminimum,factory reset, in the device provider's network. If a devicerequirespresents a user AoR in thedevice profileenrollment request, the PDS can challenge it. To respond tobe ablesuch authentication challenges, the device needs tofunction effectively. However,have associated credentials. Thus, any of the configuration methodsspecified in this document may failindicated above need to providea device with a profile. To illustratethe user credentials along withan example, considerany AoRs. Additionally, AoRs are typically known by PDSs that serve thecasedomain indicated by the AoR. Thus, devices can only present the configured AoRs in the respective domains. An exception is the use of federated identities. This allows a devicethat finds itself behindto use alocal network which does not provide information about DNS serversuser's AoR inthe network (for example, misconfigured home network). In such cases, it wouldmultiple domains. The configured user or device AoR and associated credentials can bebeneficial to employ an alternative means to obtainused in applicable domains for any of the profileinformation (for example, resolvable DNS Servers could be parttypes specified by this framework. In the absence of the deviceprofile). While this specification recommends that such a method be made available, it also specifies one such option using HTTP thator user AoR, the device isdescribed in this sub-section. devicesnot expected toencounter scenarios where propogation of thecontain any other credentials. Future enhancements can specify additional identities and credentials. 6.2.4. Securing Profile Enrollment A device requests profilecan be hindered may employ the specified -data by transmitting an enrollment request using cached, configured orany alternative - process.discovered data. Themethod being described involvesenrollment request is received by a PDS that verifies thedevice to utilizeprofile type and the identity presented, such as aHTTPS URI (and any required credentials) based on either pre-configuration or manual entry byuser AoR. If the device presents a configured user(in cases where such an interfaceidentity, it ispossible). This can leadmore likely to be known by theretrieval of thenetwork and associated with credentials. If not (e.g., discovered or deviceprofile whichidentities) it maycontainnot be known by theproperties for the SUBSCRIBE Request URI and credentials for Profile Enrollment and Profile Notification. This approach bootstrapsPDS (and hence, may not be associated with credentials). If theprocess in a different stepuser identity presented in thecycle, but uses the same framework. Further, this document defines a new HTTPenrollment requestheader "Event". The syntax of the HTTP Event headeris known by thesame as the SIP Event header defined in this document. Similar toPDS, it MUST challenge theSIP Event headerrequest; an exception is thepurpose ofcase where theHTTP Event headerdata being provided is not particular todefinethecontent ofpresented user identity. If thestate informationdevice successfully responds tobe retrieved. In particular,thestate informationchallenge, it is provided the initial notification which contains thedevice, user or local-networkprofilefordata within, or via content indirection. To ensure that thedevice. The SIP Event header parameters for this event package ("profile-type", "vendor", "model", "version") are also mandatory forPDS providing theHTTP Event header as they are used to provide information asdata belongs towhat profile type is requested alongthe domain associated withinformation aboutthe identity, the devicewhich may impactSHOULD authenticate thecontentssource of theprofile. Whennotifications. Since the devicestartsonly directly communicates withretrieval oftheprofile via HTTPS (instead ofnext-hop SIP entity (which may or may not be the PDS) it SHOULD establish a 'next-hop SIPSUBSCRIBEentity authenticated TLS session prior to transmitting theevent package), the device MUST provide the Event header defined. 5.5.2. Device Typesenrollment request. Theexamples in this framework tend to associate devicesnext-hop SIP entity SHOULD have a secure communications channel withentities that are accessible to end-users. However, this is not necessarilytheonly type of device that can utilizePDS. If not, thespecified Framework. devices can be entities such as user Interfaces (that allow for device Configuration), entities inPDS SHOULD provide thenetwork that do not directly communicate with any users (for example, Service Provider deployed gateways) or elements innotifications and include theService Provider's network (for example,SIPservers). 5.5.3. Profile Data This framework does not specifyIdentity header. If thecontents for any profile type. Follow-on standardization activities can address profile contents. However,PDS wants to ensure privacy in such situations, itmakesMAY provide only content indirection information in thefollowing assumptionsnotifications. Content indirection which results in a secure communications channel, such as HTTPS, will ensure data integrity andrecommendations: o Whenprotection. Profile-specific requirements follow. 6.2.4.1. Local-network profile Device Requirements - If the devicereceives multiple profiles,has a configured user AoR associated with thecontents of each profile type will only contain data relevant tolocal network domain then theentity it represents. As an example, consider adevicethat obtains allSHOULD establish a Server Identity verified TLS session with thedefined profiles. Information pertaining tonext-hop SIP entity. Exceptions are cases where thelocal networkdevice iscontained in the 'local-network' profile andconfigured notthe'user' profile. Thisto do so (e.g., via previously obtained, authenticated profile data). - If the device does notpreclude relevant data abouthave adifferent entity from being included inconfigured user AoR it MAY still establish aprofile type, for example,next-hop entity verified TLS session. - If an attempted next-hop SIP entity verified TLS session succeeds: * the'device' profile type may contain information aboutdevice MUST transmit theusers allowedenrollment request with the user AoR (if configured); * the device MUST respond toaccess services viaan authentication challenge. - If thedevice. A profile may also contain starting informationTLS session fails toobtain subsequent Profiles o Data overlap SHOULDverify the next-hop SIP entity (i.e., the domain name could not beavoided across profile types, unless necessary. If data overlap is present, prioritization ofverified) thedata is left to data definitions. As an example,device MUST NOT continue with the current enrollment request. However, the deviceprofile may containMUST retry by trying to establish server identity verified TLS sessions with other next-hop entities (obtained via [RFC3263]. If the list ofcodecs to be used bynext-hop entities has been exhausted then: * if the device has a user interface, and unless explicity configured not to, the device SHOULD prompt the userProfile (for aif it can continue without TLS; * unless indicated otherwise via configuration or the user, the device MUST retry enrollment without TLS and without the useronAoR. - If an attempted next-hop SIP entity verified TLS session fails (i.e., thedevice) may containPDS does not support TLS) thecodecs preferred bydevice MUST transmit theuser. Thus,enrollment request, without thesame data (usable codecs) is present in two profiles. However,user AoR. - In thedata definitions may indicate thatabsence of a Server Identity authenticated TLS session with the next-hop SIP entity: * the device MUST NOT respond tofunction effectively,anycodec chosen for communication needs to be present in bothauthentication challenges; * theprofiles. 5.5.4. Profile Data Frameworks This framework specifieddevice MUST ignore notifications containing sensitive profile data. PDS Requirements - If an enrollment request contains a user AoR that will result inthis document does not addressuser-specific profile data, then the PDS MUST successfully authenticate the user before providing user-specific profile datarepresentation, storage- If user authentication fails the PDS MAY refuse enrollment, orretrieval protocols.provide profile data without the user-specific information. - Itassumesis to be noted thatthe PDS hasif aPCC based onPDS attempts authentication without an existingor other Profile Data Frameworks, for example, XCAP ([I-D.ietf-simple-xcap]). Whilenext-hop authenticated TLS session, it will fail. - A PDS that does notimpose vast constraints on any such framework, it does allow for the propagation of profilesupport TLS MUST use content indirection toPDS (specifically the PCC). Thus, Profile Data or Retrieval frameworks used in conjunction with this framework MAY consider techniquesa PCC that supports authentication and integrity protection forpropagating incremental, atomic changes toconveying sensitive profile data. - If thePDS. For example,enrollment request did not occur over ameans for propagating changes tonext-hop authenticated TLS session, a PDSis definedthat supports SIP Identity MUST include the SIP Identity header inXCAP ([I-D.ietf-simple-xcap]). 5.5.5. Additional Profile Types This document specifies three profile types: local-network, devicethe initial anduser. However, there may be use cases for additional profile types. For example, profile types for application specific profile data. Definition of such additionalsubsequent change notifications 6.2.4.2. Device profiletypes is not prohibited, but considered out of scope for this document. 5.5.6. Deployment considerations The framework defined in this document was designedDevice Requirements A device presents either a device identity or a configured device AoR toaddress various deployment considerations, some of which are highlighted below. Provider relationships: o The local network provider andobtain theSIP service providerdevice profile. If configured with a device AoR, it canofteneither bedifferent entities, with no administrativea SIPS URI orbusiness relationship with each other; o There may be multiple SIP service providers involved, one for each service thatauser subscribes to (telephony service, instant messaging, etc.); this Framework doesSIP URI. If it is notspecify explicit behavior in such a scenario, but it does not prohibit its usage either o Each user accessing services viapre- configured then thesamedevicemay 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 particularuses the devicemay 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 servicesidentifier in association with methods specified [RFC3263]. If the deviceuser interface; o Each user may have different personal information applicable to use ofis using thedevice, either as related to particular services, or independent of them. 6. Event Package Definition The frameworkmethods specified inthis document proposes and specifies[RFC3263] it MUST prefer SIPS over SIP. If it obtains anew SIP Event Package as allowed by [RFC3265]. The purpose is to allow for devices to subscribe to specific profile types with PDSs andSIPS URI for thePDSs to notifynext-hop SIP entity, thedevices with - or pointersdevice MUST attempt to- profile data. The requirementsestablish next-hop authenticated TLS session (as specified in[RFC3265] apply to this package. The following sub-sections specify[RFC3261]). If theEvent Package descriptiondevice is configured with a device AoR and it successfully establishes a next-hop authenticated TLS session then it MUST respond to an authentication challenge. In any case, if theassociated requirements. The framework requirements are defined in Section 5. 6.1. Event Package Name The name of this packageTLS establishment fails (e.g., the PDS does not implement TLS) or it is"ua-profile". This value appears inunsuccessful (e.g., theEvent header field present in SUBSCRIBE and NOTIFY requests for this package as defined in [RFC3265]. 6.2. Event Package Parameters This package definesconnecting SIP entity is not thefollowing new parameters forexpected domain) theevent header: "profile-type", "vendor", "model", "version", "effective-by", "device-id"device MUST consider this an enrollment failure and"network-user". The following rules apply: o Alltry an alternate next-hop SIP entity (or declare an enrollment failure if all thenew parameters, withattempts have been exhausted). In theexceptionabsence of a next-hop SIP entity authenticated TLS session: - the"effective-by" parameterdevice MUSTonly 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 andNOT respond to any authentication challenges; - the device MUSTbe ignored if it appears in SUBSCRIBE requests The semantics of these new parametersignore notifications containing sensitive profile data. PDS Requirements PDS requirements arespecified inthefollowing sub-sections. 6.2.1. profile-type The "profile-type" parameter is used to indicatesame as that of thetoken namelocal-network profile, with one addition. A PDS MUST NOT accept enrollment requests with a SIPS URI in the absence of a secure communications channel (such as a TLS session from the device or a trusted proxy). 6.2.4.3. User profiletype theA device requesting a useragent wishes to obtain dataprofile will use a user AoR that is either a SIP URI orURIsa SIPS URI. In either case, the requirements for the device andto be notified of subsequent changes. This document defines three logical types of profiles and their token names. Theythe PDS areas follows: local-network Specifying "local-network" type profile indicatesthedesire for profile data (URIsame as whencontent indirection is used) specific tothelocal network.deviceSpecifying "device" type profile(s) indicates the desirerequests a device profile. In addition, PDSs MUST NOT accept user profile enrollment requests for unknown users. 6.2.5. Securing Content Retrieval Initial or change notifications following a successful enrollment can either provide a device with the requested profiledata (URI whendata, or use content indirectionis used)andchange notification of the contents of the profile that is specificredirect it to a PCC that can provide thedevice or user agent. user Specifying "user" typeprofileindicates the desire fordata. This document specifies HTTP and HTTPS as content retrieval protocols. If the profiledata (URI whenis provided via content indirectionis used)andchange notification of thecontains sensitive profile data then the PDS MUST use a HTTPS URI for content indirection. PCCs and devices MUST NOT use HTTP for sensitive profile data. A device MUST authenticate theuser. The "profile-type" is identified is identifiedPCC as specified inthe Event header parameter: profile-type.[RFC2818], Section 3.1. 6.2.6. Securing Change Notification Aseparate SUBSCRIBE dialog is used for each profile type. Thesuccessful profiletype associated withenrollment results in an initial notification. If thedialogdevice requested enrollment via a SIP subscription with a non- zero 'Expires' parameter, it canthen be used to infer which profile type changed and is containedalso result in change notifications for theNOTIFY or content indirection URI. The Accept headerduration of theSUBSCRIBE request MUST includesubscription. If theMIME types for all profile content types for whichdevice established next-hop authentication TLS then any such notifications SHOULD be sent over thesubscribing user agent wishes to retrieve profiles or receive change notifications. Insame TLS session. If thefollowing 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 inTLS session exists, theprofile-type parameter may represent a class or set ofdevice MUST ignore any notifications sent outside the TLS session. If no such TLS session exists, the PDS MUST NOT include any sensitive profileproperties. Follow-on standards defining specificdata. If no such TLS session exists, the PDS MUST NOT accept any sensitive profilecontents may find it desirabledata and ignore such notifications. A PDS that does not support TLS MUST use content indirection todefine additional tokensa PCC that supports authentication and integrity protection forthe profile-type parameter. Alsoconveying sensitive profile data. 6.3. Additional Considerations This section provides additionalcontent types may be defined alongconsiderations such as further details on enrollment withtherelated backoff and retry methods, guidelines on profileformats that can be used in the Accept header of the SUBSCRIBE to filter or indicate whatdatasets 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 alladditional profile types.The implementer SHOULD use their DNS domain name (for example, example.com) as the value of the "vendor" parameter so that it6.3.1. Profile Enrollment Request Attempt A state diagram representing a device requesting any specific profile defined by this framework isknown to be unique. These parameters are usefulshown in Figure 6. +------------+ | Initialize | +-----+------+ | | V +-------------+ | Prepare | +--------->| Enrollment |<------------------+ | | Request | | | +------+------+ | +------+------+ | | | Failure | Enroll. Req. prepared | +-->| Handling & | /Send Req | | | Delay | | | | +-------------+ V | | ^ ^ +-------------+ | | | | | Await | | | | +--------+ Enrollment | | | | Timeout, | acceptance | | | | non-2xx/- +------+------+ | | | | | | Timeout 200 OK/- Enrollment | /Terminate | Timeout/- | Enrollment V | | | +--------------+ | | | | Enrollment | | | +------------+ accepted | | Retries Exceeded |(await NOTIFY)| | /Retry Enrollment +---+------+---+ | | | | | | | | | | NOTIFY w. Content Ind| | NOTIFY w. Profile | | /Retrieve Profile | | /Accept Profile | | +------------+ +------------+ | | | | | | V V | | +------------+ +------------+ | +-----+ Retrieving | Retrieved | Enrollment +---+ ,->| Profile +--/Apply Profile-->| Successful | / | | |(monitoring)|<--. Timeout +--+---------+ +--+----+----+ : /Retry ; ^ | : ; `------' | NOTIFY w. Cont.Ind | `-------' +---/Retrieve Profile-----+ NOTIFY w. Profile /Apply Profile Figure 6: Device State Diagram As a reminder: o The timeout for SIP messages is specified by [RFC3261] o The timeout for profile retrieval using content indirection will be as specified by profile retrieval protocols employed In addition, since profile enrollment is a process unique to this framework, thePDSdevice MUST follow the enrollment attempt along with exponential backoff and retry mechanisms as indicated in Figure 7. Function for Profile Enrollment () Iteration i=0 Loop: Attempt Loop: For each SIP Subscription URI Loop: For each next-hop SIP entity obtained via RFC3263 - Prepare & transmit Enrollment Request - Await Enrollment Acceptance and initial NOTIFY + If the profile enrollment is successful = Abort this function() + If profile enrollment fails due toaffectan explicit failure or a timeout as specified in RFC3261 = Continue with this function() End Loop: Next-hop SIP entity contact End Loop: SIP Subscription URI formation (Note: If you are here, profile enrollment did not succeed) + Is any valid cached profile data available? = If yes, use it and continue with this function() + If the enrollment request is for a non-mandatory profile = then spawn the next profile and continue with this function() - Delay for 2^i*(64*T1); -- this is exponential backoff - increment i; - If i>8, reset i=0; End loop: Attempt End Function() Figure 7: Profile Enrollment Attempt (pseudo-code) The pseudo-code above (Figure 7) allows for cached profilesprovided. In some scenariosto be used. However, any cached Local Network profile MUST NOT be used unless the device can ensure that it isdesirable toin the same local network which provided the cached data. This framework does not providedifferentany procedures for local network recognition. Any cached device and user profilesbased upon these parameters.MUST only be used in domains that they are associated with. For example,feature property Xa cached device profile is used only when the associated domain matches the current device provider's domain. If a PDS wants to invalidate a profile it may do so by transmitting a NOTIFY with an 'empty profile' (not to be confused with an empty NOTIFY). A device receiving such a NOTIFY MUST discard the applicable profile (i.e., it cannot even store it in the cache). Additionally, if aprofile may work differentlyfactory reset is available and performed ontwo versions ofa device, it MUST reset thesame user agent. This givesdevice to its initial state prior to any configuration. Specifically, thePDSdevice MUST set theabilitydevice back tocompensate for or take advantagethe state when it was originally distributed. The order of profile enrollment is important. For thedifferences. Inprofiles specified in this framework, thefollowing ABNF definingdevice must enrol in thesyntax, EQUALorder: local-network, device andquoted-string are defined in [RFC3261]. Vendor = "vendor" EQUAL quoted-string Model = "model" EQUAL quoted-string Version = "version" EQUAL quoted-string 6.2.3. device-iduser. The"device-id" parameter MUST be set when subscribing for "local- network"pseudo-code presented earlier (Figure 7) differentiates between 'mandatory' and 'non-mandatory' profiles. Thisidentifiesdistinction is left to profile data definitions. It is to be noted that this framework does not allow thedevice requestingdevices to inform thelocal- network profile. IfPDSs of profile retrieval errors such as invalid data. Follow-on standardization activities are expected to address this feature. 6.3.2. Device Types The examples in this framework tend to associate devices with entities that are accessible to end-users. However, this is not necessarily thevalueonly type of device that can utilize the"profile-type" parameter isspecified Framework. Devices can be entities such as SIP Phones or soft clients, with or without user interfaces (that allow for device Configuration), entities in the network that do not directly communicate with any users (e.g., gateways, media servers, etc) or network infrastructure elements e.g., SIP servers). 6.3.3. Profile Data This framework does not"local-network",specify the"device-id" parameter has no defined meaning and is ignored. Incontents for any profile type. Follow-on standardization activities are expected to address profile contents. However, the framework provides the followingABNF, EQUAL, LDQUOT, RDQUOTrequirements andaddr-spec are defined in [RFC3261]. Device-Id = "device-id" EQUAL LDQUOT addr-spec RDQUOT 6.2.4. network-userrecommendations for profile data definitions: o The"network-user" parameter MAYdevice profile type MUST specify parameters to configure the identities and credentials. These parameters may beprovidedoptional or mandatory and will be used for dynamically configuring devices that initialize in asubscription fornetwork without any pre-configuration. o Each profile MUST clearly identify if it may contain any sensitive data. Such profiles MUST also identify the data elements that are considered sensitive, i.e., data that cannot be compromised. As an example, a"device" profile. Indevice profile definition may identify itself as containing sensitive data and indicate data suchcases theas deviceis requesting the PDScredentials torecognize the indicated user asbe sensitive. o When thedefault user for itself. Ifdevice receives multiple profiles, thevaluecontents of each profile type SHOULD only contain data relevant to the"profile-type" parameter is not "device",entity it represents. As an example, consider a device that obtains all the"network-user" parameter has nodefinedmeaning and is ignored. Ifprofiles. Information pertaining to the"network-user" parameterlocal network isprovided in the SUBSCRIBE request, it MUST be presentcontained in theNOTIFY request as well. In the following ABNF, EQUAL, LDQUOT, RDQUOT'local-network' profile andaddr-spec are defined in [RFC3261]. Network-User = "network-user" EQUAL LDQUOT addr-spec RDQUOT 6.2.5. effective-by parameter The "effective-by" parameternot the 'user' profile. This does not preclude relevant data about a different entity from being included in a profile type, e.g., theEvent header of'device' profile type may contain information about theNOTIFY request specifiesusers allowed to access services via themaximum numberdevice. 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 ofseconds beforetheuser agent must attemptdata is left tomakedata definitions. As an example, thenewdevice profileeffective. The "effective-by" parameter MAY be provided inmay contain theNOTIFY request for anylist of codecs to be used by theprofile types. A value of 0 (zero) indicates thatdevice and thesubscribinguseragent must attempt to makeProfile (for a user on theprofiles effective immediately (despite possible service interruptions). This givesdevice) may contain thePDScodecs preferred by thepower to control whenuser. Thus, theprofile is effective. This may be important to resolve an emergency problem or disable a user agent immediately. The "effective-by" parametersame data (usable codecs) isignoredpresent inall messages other than the NOTIFY request. Intwo profiles. However, thefollowing 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 whichdata definitions mayoccur in SUBSCRIBE requests. These examples are not intendedindicate that to function effectively, any codec chosen for communication needs to becomplete SUBSCRIBE requests. Event: ua-profile;profile-type=device; vendor="vendor.example.com";model="Z100";version="1.2.3" Event: ua-profile;profile-type="user"; vendor="premier.example.com";model="trs8000";version="5.5"present in both the profiles. 6.3.4. Profile Data Frameworks Thefollowing are example Event headers which may occurframework specified inNOTIFY requests. These example headers arethis document does notintended to be complete SUBSCRIBE requests. Event: ua-profile;effective-by=0 Event: ua-profile;effective-by=3600 The following table showsaddress profile data representation, storage or retrieval protocols. It assumes that the PDS has a PCC based on existing or other Profile Data Frameworks. While this framework does not impose specific constraints on any such framework, it does allow for theusepropagation ofEvent header parametersprofile content to the PDS (specifically the PCC) from a network element or the device. Thus, Profile Data or Retrieval frameworks used inSUBSCRIBE requestsconjunction with this framework MAY consider techniques for propagating incremental, atomic changes to the PDS. One means for propagating changes to a PDS is defined in XCAP ([RFC4825]). 6.3.5. Additional Profile Types This document specifies three profile types:profile-type ||local-network, 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 meaningandshoulduser. However, there may beignored. The following table shows theuse cases for additional profile types. e.g., profile types for application specific profile data or to provide enterprise-specific policies. Definition ofEvent header parameters in NOTIFY requestssuch additional profile types is not prohibited, but considered out of scope forthe threethis document. Such profiletypes: profile-type ||definitions MUST specify the order of retrieval with respect to all the other profiles such as the local-network, device|and 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 useprofile types defined in this document. 6.3.6. 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 theSUBSCRIBE request body. If present, it MUSTSIP service provider can often beignored. Future enhancements to the frameworkdifferent entities, with no administrative or business relationship with each other. o There mayspecify a usebe multiple SIP service providers involved, one forthe SUBSCRIBE request body (for example,, mechanisms using etags to minimize Profile Notifications to devices with current profile versions). 6.4. Subscription Duration The duration ofeach service that asubscription is specificuser subscribes toSIP deployments and no specific recommendation is made by(telephony service, instant messaging, etc.); thisEvent Package. If absent,Framework does not specify explicit behavior in such avalue of 86400 seconds is RECOMMENDED sincescenario, but it does not prohibit its usage either. o Each user accessing services via thepresence (or absence)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 (e.g., a particular device may allow for many users to obtain subscriptionis not time criticalservices through it, and individual users may have access tothe regular functioningmultiple devices). o Each user may have different preferences for use of services, and presentation of those services in thePDS. It isdevice user interface. o Each user may have different personal information applicable tobe noted that a one-time fetchuse ofa profile can be accomplished by settingthe'Expires' parameterdevice, either as related toa valueparticular services, or independent ofZero, as specified in [RFC3265]. 6.5. NOTIFY Bodiesthem. 7. Event Package Definition The frameworkspecifying thespecified in this document proposes and specifies a new SIP Event Packageallowsas allowed by [RFC3265]. The purpose is to allow for devices to subscribe to specific profile types with PDSs and for theNOTIFY bodyPDSs tocontainnotify the devices with the profile data ora pointercontent indirection information. The requirements specified in [RFC3265] apply to this package. The following sub-sections specify theprofile data using content indirection.Event Package description and the associated requirements. The frameworkdoes not define any profile data and delegates specificationrequirements are defined in Section 6. 7.1. Event Package Name The name ofutilized MIME types Profile Data Frameworks. For profile data delivered via content indirection, the following apply: othis package is "ua-profile". This value appears in theContent-ID MIME header,Event header field present in SUBSCRIBE and NOTIFY requests for this package asdescribeddefined in[RFC4483] MUST be used[RFC3265]. 7.2. Event Package Parameters This package defines the following new parameters foreach Profile document URI o at a minimum,the"http:"event header: "profile-type", "vendor", "model", "version", 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])"effective-by" TheNOTIFY body SHOULD include a MIME type specified in the 'Accept' header offollowing rules apply: o All theSUBSCRIBE. Further, ifnew parameters, with theAccept headerexception of theSUBSCRIBE included the MIME type message/external-body (indicating support for content indirection) the content indirection SHOULD"effective-by" parameter MUST only be used intheSUBSCRIBE requests and ignored if they appear in NOTIFY requests. o The "effective-by" parameter is for use in NOTIFYbody for providing the profiles. If none are specified, the Profile Data frameworks are responsible for,requests only and MUSTspecify, the MIME type tobeassumed. 6.6. Notifier Processing of SUBSCRIBE Requests A successfulignored if it appears in SUBSCRIBErequest resultsrequests. The semantics of these new parameters are specified ina NOTIFY with either profile contents or a pointer to it (via Content Indirection). IftheNOTIFYfollowing sub-sections. 7.2.1. profile-type The "profile-type" parameter isexpectedused tocontain profile contents orindicate theNotifier is unsure,token name of theSUBSCRIBE SHOULD be either authenticatedprofile type the user agent wishes to obtain data ortransmitted over an integrity protected SIP communication channels. ExceptionsURIs for and toauthenticating such SUBSCRIBEs include cases where the identitybe notified ofthe Subscriber is unknownsubsequent 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 theNotifier is configured to accept such requests. The Notifier MAY also authenticate SUBSCRIBE messages even if the NOTIFY is expected to only contain a pointer todesire for profiledata. Securingdatasent via Content Indirection(URI when content indirection iscovered in Section 9. Ifused) specific to theprofilelocal network. device: Specifying "device" typeindicated inprofile(s) indicates the"profile-type" Event header parameter is unavailable ordesire for theNotifierprofile data (URI when content indirection isconfigured not to provide it, the Notifier SHOULD return a 404 response toused) and change notification of theSUBSCRIBE request. Ifcontents of thespecific user or deviceprofile that isunknown,specific to theNotifier MAY either acceptdevice orrejectuser agent. user: Specifying "user" type profile indicates thesubscription. Whendesire for theEvent header "profile-type"profile data (URI when content indirection is"device"used) and change notification of theuser agent has providedprofile content for theuser's AORuser. The "profile-type" is identified is identified in the"network-user" parameter, theEvent header parameter: profile-type. A separate SUBSCRIBE dialog is used for each profiledelivery server MAY set or change the default usertype. The profile type associated with thedevice indicateddialog can then be used to infer which profile type changed and is contained in theSubscription request. However, the Notifier SHOULD authenticate the user indicated before making such a change. 6.7. Notifier Generation ofNOTIFYRequests As specified in [RFC3265],or content indirection URI. The Accept header of theNotifier MUST always send a NOTIFYSUBSCRIBE requestupon accepting a subscription. IfMUST include thedevice or user is unknown andMIME types for all profile content types for which theNotifier choosesubscribing user agent wishes toacceptretrieve profiles or receive change notifications. In thesubscription,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 theNotifier MAY either respond withprofile-type parameter may represent a class or set of profiledata (for example, defaultproperties. Follow-on standards defining specific profiledata) or provide nocontents may find it desirable to define additional tokens for the profile-type parameter. Also additional content types may be defined along with the profileinformation (i.e. no bodyformats that can be used in the Accept header of the SUBSCRIBE to filter orcontent indirection). Ifindicate what data sets of theURIprofile are desired. 7.2.2. 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 requestis a known identity and the requestedfor all profileinformation is available (i.e.types. The implementer SHOULD use their DNS domain name (e.g., example.com) asspecified intheprofile-type parametervalue of theEvent header),"vendor" parameter so that it is known to be unique. These parameters are useful to theNotifier SHOULD sendPDS to affect the profiles provided. In some scenarios it is desirable to provide different profiles based upon these parameters. e.g., feature property X in aNOTIFY with profile data. Profile data MAY be sent asprofilecontents or via Content Indirection (ifmay work differently on two versions of thecontent indirection MIME type was included insame user agent. This gives theAccept header). To allowPDS the ability to compensate forContent Indirection,or take advantage of theSubscriber MUST supportdifferences. In the"http:" or "https:" URI schemas. Iffollowing ABNF defining theSubscriber wishes to support alternative URI schemas it MUST be indicatedsyntax, EQUAL and quoted-string are defined in [RFC3261]. Vendor = "vendor" EQUAL quoted-string Model = "model" EQUAL quoted-string Version = "version" EQUAL quoted-string 7.2.3. effective-by parameter The "effective-by" parameter in the"schemes" ContactEvent headerfieldof the NOTIFY request specifies the maximum number of seconds before the user agent must attempt to make the new profile effective. The "effective-by" parameteras definedMAY be provided in[RFC4483]. Ifthesubscriber does not specifyNOTIFY request for any of theURI scheme,profile types. A value of 0 (zero) indicates that theNotifier may use either "http:" or "https:". The Notifier MAY specify whensubscribing user agent must attempt to make thenewprofilesmust be madeeffectivebyimmediately (despite possible service interruptions). This gives theSubscriber by specifying a maximum time in seconds (zeroPDS the power to control when the profile is effective. This may be important to resolve an emergency problem ormore)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 7.2.4. Summary of eventheader parameter. Ifparameters The following are example Event headers which may occur in SUBSCRIBE requests. These examples are not intended to be complete SUBSCRIBE requests. Event: ua-profile;profile-type=device; vendor="vendor.example.com";model="Z100";version="1.2.3" Event: ua-profile;profile-type=user; vendor="premier.example.com";model="trs8000";version="5.5" The following are example Event headers which may occur in NOTIFY requests. These example headers are not intended to be complete SUBSCRIBE requests. Event: ua-profile;effective-by=0 Event: ua-profile;effective-by=3600 The following table shows the use of Event header parameters in SUBSCRIBEwas received over an integrity protected SIP communications channel,requests for theNotifierthree profile types: profile-type || device | user | local-network ============================================= vendor || m | m | m model || m | m | m version || m | m | m effective-by || | | m - mandatory s - SHOULDsend the NOTIFY overbe provided o - optional Non-specified means that thesame channel. 6.8. Subscriber Processingparameter has no meaning and should be ignored. The following table shows the use of Event header parameters in NOTIFYRequests A Subscriber to this eventrequests for the three profile types: profile-type || device | user | local-network ============================================= vendor || | | model || | | version || | | effective-by || o | o | o 7.3. SUBSCRIBE Bodies This packageMUST adhere todefines no use of theNOTIFYSUBSCRIBE requestprocessing behavior specified in [RFC3265].body. Ifthe Notifier indicated an effective time (using the "effective-by" Event Header parameter),present, itSHOULD 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 cannotMUST beapplied within the recommended timeframe and this affects device behavior, any actionsignored. Future enhancements tobe taken SHOULD be defined bytheprofile data definitions. By default,framework may specify a use for theSubscriber is RECOMMENDEDSUBSCRIBE request body (e.g., mechanisms using etags tomake the profiles effective as soon as possible. The Subscriber MUST always support "http:" or "https:" and be preparedminimize Profile Notifications toaccept NOTIFY messagesdevices withthose URI schemas.The subscriber MUST also be prepared to receivecurrent profile versions). 7.4. Subscription Duration The duration of aNOTIFY request withsubscription is specific to SIP deployments and nobody. The subscriber MUST NOT rejectspecific recommendation is made by this Event Package. If absent, a value of 86400 seconds (24 hours; 1 day) is RECOMMENDED since theNOTIFY request with no body. Thepresence (or absence) of a device subscriptiondialog MUST NOTis not time critical to the regular functioning of the PDS. It is to beterminated bynoted that aNOTIFY with no body. 6.9. Handlingone-time fetch ofForked Requests This Event package allowsa profile can be accomplished by setting thecreation of only one dialog as'Expires' parameter to aresultvalue ofan initial SUBSCRIBE requestZero, asdescribedspecified insection 4.4.9 of[RFC3265].It does not support the creation of multiple subscriptions using forked SUBSCRIBE requests. 6.10. Rate of Notifications7.5. NOTIFY Bodies Therate of notifications for the profiles in thisframeworkis deployment specific, but expected to be infrequent. Hence,specifying the Event Packagespecification does not specify a throttling or minimum period betweenallows for the NOTIFYrequests 6.11. State Agents State agents are not applicablebody tothis Event Package. 7. Examples This section provides examples along with sample SIP message bodies relevantcontain the profile data or a pointer tothis framework. Boththeexamples are derived fromprofile 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 asnapshotminimum, 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] and XCAP [RFC4825] ). The NOTIFY body SHOULD include a MIME type specified in the 'Accept' header of the SUBSCRIBE. Further, if the Accept header ofSection 4.1, specificallytherequestSUBSCRIBE included the MIME type message/external-body (indicating support for content indirection) then thedevice profile. The examples are purely informative andPDS MAY use content indirection incasethe NOTIFY body for providing the profiles. 7.6. Notifier Processing ofconflictsSUBSCRIBE Requests A successful SUBSCRIBE request results in a NOTIFY with either profile contents or a pointer to it (via Content Indirection). If theframeworkNOTIFY is expected to contain profile contents orprotocols used for illustration,thelatter shouldNotifier is unsure, the SUBSCRIBE SHOULD bedeemed normative. 7.1. Example 1: Device requesting profile This example illustrateseither authenticated or transmitted over an integrity protected SIP communication channels. Exceptions to authenticating such SUBSCRIBEs include cases where thedetailed message flows betweenidentity of thedeviceSubscriber is unknown and theSIP Service Provider's network for requesting and retrievingNotifier 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(the flow usesdata. Securing data sent via Content Indirection is covered in Section 10. If thedeviceprofileas an example). The following are assumed for this example: o Devicetype indicated in the "profile-type" Event header parameter isassumed to have established local network connectivity; NAT and Firewall considerations are assumedunavailable or the Notifier is configured not tohave been addressed byprovide it, theSIP Service Provider o examples areNotifier SHOULD return asnapshot only and do not illustrate all404 response to the SUBSCRIBE request. If the specific user or device is unknown, the Notifier MAY either accept or reject theinteractions betweensubscription. 7.7. 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 theService Provider's network (and none betweenNotifier chooses to accept theentities insubscription, theSIP Service Provider's network) o All SIP communicationNotifier MAY either respond with profile data (e.g., default profile data) or provide no profile information (i.e. no body or content indirection). If theSIP Service Provider happens via a SIP Proxy o HTTP is assumed to beURI in theProfile Data method used (any suitable alternative can be used as well) o TLSSUBSCRIBE request isassumed 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 diagrama known identity andan explanation ofthemessages follow. +----------------------+ +--------+ | 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)requested profile information is available (i.e. as specified in thedevice transmitsprofile-type parameter of the Event header), the Notifier SHOULD send arequestNOTIFY 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'device' profile usingSubscriber MUST support theSIP SUBSCRIBE utilizing"http:" or "https:" URI schemas. If theEvent Package specifiedSubscriber wishes to support alternative URI schemas it MUST be indicated inthis framework. * Note: Some ofthe "schemes" Contact headerfields (for example, Event, via) are continued onfield parameter as defined in [RFC4483]. The Notifier MUST NOT use any schema that was not indicated in the "schemas" Contact header field. The Notifier MAY specify when the new profiles must be made effective by the Subscriber by specifying aseparate line due to format constraintsmaximum time in seconds (zero or more) in the "effective-by" event header parameter. If the SUBSCRIBE was received over an integrity protected SIP communications channel, the Notifier SHOULD send the NOTIFY over the same channel. 7.8. Subscriber Processing of NOTIFY Requests A Subscriber to thisdocument 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)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 (e.g., emergency sessions are in progress). When profile data cannot be applied within theSUBSCRIBE request is receivedrecommended timeframe and this affects device behavior, any actions to be taken SHOULD be defined bya SIP Proxy intheService Provider's network which transmits itprofile data definitions. By default, the Subscriber is RECOMMENDED to make thePDS.profiles effective as soon as possible. ThePDS accepts the responseSubscriber MUST always support "http:" or "https:" andrespondsbe prepared to accept NOTIFY messages with those URI schemas.The subscriber MUST also be prepared to receive a200 OK * Note:NOTIFY request with no body. Thedevice and the SIP proxy may have established a secure communications channel (for example, TLS) (NTFY) subsequently,subscriber MUST NOT reject thePDS transmitsNOTIFY request with no body. The subscription dialog MUST NOT be terminated by aSIPNOTIFYmessage indicating the profile location * Note: Somewith no body. 7.9. Handling of Forked Requests This Event package allows thefields (for example, content-type) are continued oncreation of only one dialog as aseparate line due to format constraintsresult 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. 7.10. Rate of Notifications The rate of notifications for the profiles in thisdocument 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 acceptsframework is deployment specific, but expected to be infrequent. Hence, the Event Package specification does not specify a throttling or minimum period between NOTIFYmessage and respondsrequests 7.11. State Agents State agents are not applicable to this Event Package. 8. Examples This section provides examples along witha 200 OK (XReq) oncesample SIP message bodies relevant to this framework. Both thenecessary secure communications channel is established,examples are derived from a snapshot of Section 5.1, specifically thedevice sends an HTTPrequesttofor theHTTP server indicateddevice profile. The examples are purely informative and in case of conflicts with theNOTIFY (XRes) the HTTP server responds to the request via a HTTP response containingframework or protocols used for illustration, theprofile contents 7.2.latter should be deemed normative. 8.1. Example2:1: Deviceobtaining change notification The followingrequesting profile This example illustrates thecase where a user (X) is simultaneously accessing services via two different devices (for example, Multimedia entities on a PC and PDA)detailed message flows between the device andhas access to a user Interface (UI) that allowsthe SIP Service Provider's network forchanges torequesting and retrieving theuser profile.profile (the flow uses the device profile as an example). The following are assumed for this example: oThe devices (A & B) obtainDevice is assumed to have established local network connectivity; NAT and Firewall considerations are assumed to have been addressed by thenecessary profiles fromSIP Service Provider. o Examples are snapshots only and do not illustrate all the interactions between the device and the Service Provider's network (and none between the entities in thesameSIP ServiceProviderProvider's network). oTheAll SIP communication with the SIP Service Provideralso provideshappens via auser Interface (UI) that allows the userSIP Proxy. o HTTP over TLS is assumed tochange preferences that impactbe theuser profileProfile Data method used (any suitable alternative can be used as well). 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 UA)| | 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)|<----------------------|| | | | | | SUBSCRIBE | |NOTIFY|| (SReq)|--------device profile--------->| |NOTIFY |<------||(A-NT)|<-------------------------------|| |------>| | |200|200 OK | | |(A-RS)|------------------------------->|200200 OK |<------| | (SRes)|<-------------------------------| | ||------>|| | | | | | NOTIFY| | ||NOTIFY|<------| | | (B-NT)|<---------------|(Content Indirection)|<------| | (NTFY)|<-------------------------------| | | | 200 OK | | || (B-RS)|--------------->|200(NRes)|------------------------------->|200 OK | | |||------>| | | | | |(A-RX)|<===Retrieves User X's profile================>| | || | |<<<<<<<<<<<<< TLS establishment >>>>>>>>>>>>>| | | | HTTP Request | (XReq)|---------------------------------------------->| |(B-RX)|<= Retrieves User X's profile=>|| | HTTP Response |(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(XRes)|<----------------------------------------------| | | (SReq) theHTTP Server * Note: The UI itself can act as adeviceand 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) PDStransmits aNOTIFY message to device A indicatingrequest for thechanged profile. A sample message is shown below:'device' profile using the SIP SUBSCRIBE utilizing the Event Package specified in this framework. * Note: Some of the header fields(for example, Via)(e.g., SUBSCRIBE, Event, via) are continued on a separate line due to format constraints of thisdocument NOTIFY sip:userX@192.0.2.44document. SUBSCRIBE sip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB @example.com SIP/2.0 Event:ua-profile;effective-by=3600ua-profile;profile-type=device;vendor="vendor.example.net"; model="Z100";version="1.2.3"; From:sip:userX@sip.example.net;tag=abcdsip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB @example.com;tag=1234 To:sip:userX@sip.example.net.net;tag=1234sip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB@example.com Call-ID: 3573853342923422@192.0.2.44 CSeq:322 NOTIFY2131 SUBSCRIBE Contact: sip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB @example.com ;+sip.instance="<urn:uuid:00000000-0000-0000-0000-123456789AB0>" 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 ASIP/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 theNOTIFYresponse andsendsresponds with a 200 OK(B-NT)* Note: The device and the SIP proxy may have established a secure communications channel (e.g., TLS). (NTFY) subsequently, the PDS transmits a SIP NOTIFY messageto device Bindicating thechanged profile. A sample message is shown below:profile location * Note: Some of the fields(for example, Via)(e.g., content-type) are continued on a separate line due to format constraints of thisdocumentdocument. NOTIFYsip:userX@192.0.2.43sip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB @192.0.2.44 SIP/2.0 Event: ua-profile;effective-by=3600 From:sip:userX@sip.example.net;tag=abcesip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB@example.com ;tag=abca To:sip:userX@sip.example.net.net;tag=1235sip:urn%3auuid%3a00000000-0000-1000-0000-00FF8D82EDCB@example.com ;tag=1231 Call-ID:3573853342923422@192.0.2.433573853342923422@192.0.2.44 CSeq: 322 NOTIFY Via: SIP/2.0/UDP 192.0.2.3;branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d2branch=z9hG4bK1e3effada91dc37fd5a0c95cbf6767d0 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";URL="http://example.com/z100-000000000000.html"; size=9999;hash=123456789AAABBBCCCDD . . . (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 Packagehash=10AB568E91245681AC1B Content-Type: application/x-z100-device-profile Content-ID: <39EHF78SA@example.com> . . . (NRes) Device accepts the NOTIFY message andHTTP header. These are outlined in this section. 8.1. SIP Event Package This specification registersresponds with anew event package as defined in [RFC3265]. The following information required for this registration: Package Name: ua-profile Package or Template-Package: This200 OK (XReq) once the necessary secure communications channel isa package Published Document: RFC XXXX (Noteestablished, the device sends an HTTP request toRFC Editor: Please fillthe HTTP server indicated inXXXX withtheRFC number of this specification). PersonsNOTIFY (XRes) the HTTP server responds toContact: 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 request via a HTTP response containing the profile contents 8.2. Example 2: Device obtaining change notification The followingtableexample illustrates theadditions to the IANA SIP Header Field Parameterscase where a user (X) is simultaneously accessing services via two different devices (e.g., Multimedia entities on a PC andParameter Values: (NotePDA) and has access toRFC 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 definesanew permanent HTTP request header field: Event. Header field name: Event Applicable protocol: http Status: standard Author/Change controller: IETF Specification document(s): [RFCXXXX] (Noteuser Interface (UI) that allows for changes toRFC Editor: Please fill in XXXX withtheRFC number of this specification). 9. Security Considerationsuser profile. Theframework specified in this document allowsfollowing are assumed for this example: o The devices (A & B) obtain thepropagation of device profile data (Section 5.5.3). To accomplish this, it specifiesnecessary profiles from the same SIP Service Provider. o The SIP Service Provider also provides aProfile Life Cycle (Section 3.3)user Interface (UI) that allows the user to change preferences that impact the user profile. The flow diagram and anEvent Package (Section 6).explanation of the messages follow. o Note: TheProfile Life Cycle consistsexample only shows retrieval ofthree distinct communication channels: Profile Enrollment and Change Notification, Profile Content Retrieval,user X's profile, but it may request andProfile Change Operation. +------+ +-----+retrieve other profiles (e.g., 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)|<----------------------| | ||Device||PNC| | | | |+------+ +-----+NOTIFY| | | NOTIFY |<------| |Profile Enrollment(A-NT)|<-------------------------------| ||---------------------->|| | 200 OK |Profile Notification|(initial |<----------------------| or upon| (A-RS)|------------------------------->|200 OK |a change) +------+ +-----+| | |------>| | ||Device||PCC| | | NOTIFY| | |+------+ +-----+| NOTIFY |<------| | |Profile Request(B-NT)|<---------------| |(When content |---------------------->| indirection| |is used)|Profile Response200 OK ||<----------------------|| |+------------+ +-----+|Authorized(B-RS)|--------------->|200 OK | |PCC| |Entity|------>| | | |+------------+ +-----+| | (A-RX)|<===Retrieves User X's profile================>| | | |Profile Change Request||---------------------------------->|| | |Profile Change Response||<----------------------------------|| (B-RX)|<= Retrieves User X's profile=>| |PNC = Profile Notification Component PCC = Profile Content Component 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),| | (A-EX) Device A discovers, enrolls andzombie attacks. Even if the profile data is provided using content indirection, PCC information within theobtains notificationcan lead to threats such as denial of service attacks (rogue devices bombard the PCC with requests for a specific profile) and attemptsrelated tomodify erroneous data onto the PCC (since the location and format may be known). It is also important for the deviceuser X's profile. (A-RX) Device A retrieves user X's profile. (B-EX) Device B discovers, enrolls and obtains notification related toensureuser X's profile. (B-RX) Device B retrieves user X's profile. (HPut) Changes affected by theauthenticity ofuser via thePNC since impersonation ofuser Interface (UI) are uploaded to theService ProviderHTTP Server. * Note: The UI itself canlead to Denial of Service, Man-in-the-Middle attacks, etc. Profile Content retrieval allowsact as a device and subscribe toretrieve profile data from a PCC.user X's profile. Thiscommunication is accomplished using one of many profile delivery protocols or frameworks, butisconsidered to be out of scope within this document. However, sincenot theprofile data returned is subject tocase in thesame considerations as that sent via profile notification,example shown. (HRes) Changes are accepted by thesame threats exist. Profile Change Operation allows an authorized entity to modify profiles stored onHTTP server. (A-NT) PDS transmits aPCC. The specific entitiesNOTIFY message to device A indicating the changed profile. A sample message is shown below: Note: Some of the fields (e.g., Via) arebased on Service Provider's policy and can include trusted network elements and devices alike. The profile information storedcontinued on aPCC 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 trustedseparate line due toperform profile modifications presents threats such as denial-of-service, manipulationformat constraints ofservice, impersonation (for example, redirection to rogue networks)this document. 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 andman-in-the-middle attacks. The framework specified in this document accomplishessends a 200 OK (B-NT) PDS transmits a NOTIFY message to device B indicating thepropagationchanged profile. A sample message is shown below: Note: Some ofprofile data by utilizingthespecified "ua-profile" event package which is basedfields (e.g., Via) are continued on[RFC3265]. Thus, its usage is expecteda separate line due tocomply 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 remainderformat constraints of thissection presents the specific security requirements fordocument. 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 . . . (B-RS) Device B accepts theframework. 9.1. Profile Enrollment and Change Notification This framework specifies,NOTIFY andallows forsends a 200 OK (A-RX) Device A retrieves thepropagation of, threeupdated profiletypes: local-network, device and user. Enrollment and change notification are expectedpertaining tobe accomplished over integrity-protected SIP communication channels and following requirementsuser X (B-RX) Device B retrieves the updated profile pertaining to user X 9. IANA Considerations There arepresented: 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 complyingtwo IANA considerations associated with thisframework MUST implement thedocument, SIPDigest 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 NameEvent Package and SIP configuration profile types. These are outlined in the'SubjectAltName', establishing the PNCfollowing sub-sections. 9.1. SIP Event Package This specification registers a new event package as defined in [RFC3265]. The following information required for this registration: Package Name: ua-profile Package or Template-Package: This is ahostpackage Published Document: RFC XXXX (Note to RFC Editor: Please fill in XXXX with theService Provider's domain o a PNC capableRFC number ofpropagating local-network profiles or unauthenticated device profiles MUST supportthis 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 (the profile-type parameter has predefined values. The new event header parameters do not) The following table illustrates theuse ofadditions to the IANA SIPIdentity header as defined in [RFC4474] for inclusionHeader 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] 9.2. Registry of SIP configuration profilenotifications Eachtypes This document requests IANA to register new SIP configuration profiletype serves a different purpose, and is providedtypes at http://www.iana.org/assignments/sip-parameters underdifferent circumstances and thus presents slightly different requirements for authentication and protection of communication. local-network profile The local-network"SIP Configuration Profile Types". SIP configuration profileis provided bytypes allocations fall under thelocal network and usually contains non-sensitive data that is shared among all participantscategory "Specification Required", as explained in "Guidelines for Writing an IANA Considerations Section in RFCs" ([RFC2434]). Registrations with the IANA MUST include alocal network. However,theframework also allows forprofile type, and a published document which describes its purpose and usage. As this document specifies three SIP configuration profile types, thepresentation ofinitial IANA registration will contain theuser's AOR, if known, for possible privileged user data. This may, or may not, resultinformation shown inuser-specific information. The following requirements are presented: *thePNC MUST authenticatetable below. It also demonstrates theidentitytype of information maintained by the IANA. Profile Type Reference -------------- --------- local-network [RFCXXXX] device [RFCXXXX] user(if set[RFCXXXX] CONTACT: ------- sumanth@cablelabs.com Daniel Petrie dan.ietf AT SIPez DOT com Note toanything other thanRFC editor: Please replace RFCXXXX with thedefault) for local-network profile requests that resultRFC number assigned to this document. 10. Security Considerations The framework specified inuser-specificthis document enables profile datacontaining sensitive information; for authentication, unless other mechanismsdelivery to devices. It specifies profile delivery stages, an event package and several profile types. There areemployed, SIP Digestthree stages: Enrollment, Content Retrieval, and Change Notification. +------+ +-----+ | | | | |Device| | PNC | | | | | +------+ +-----+ | | | Profile Enrollment | |---------------------->| | | | Initial Notification | |<----------------------| | | +------+ +-----+ | | | | |Device| | PNC | | | | | +------+ +-----+ | | | Profile Enrollment | |---------------------->| | | | Change Notification | |<----------------------| | | +------+ +-----+ | | | | |Device| | PCC | | | | | +------+ +-----+ | | | Profile Request | (When content |---------------------->| indirection | | isused. If the authentication fails, theused) | Profile Response | |<----------------------| | | PNCMUST not include any user- specific information in the local-network profile *= Profile Notification Component PCC = Profile Content Component Figure 23: Profile Delivery Stages Enrollment allows a device to request a profile. To transmit thePNC MAY NOT authenticate requests forrequest thelocal-network profile that do not result in any user-specific sensitivedevice relies on cached, configured or discovered data. Such data(irrespective of the value ofincludes provider domain names, identities, and credentials. The device uses [RFC3263] to discover theFrom field) *next-hop SIP entity which can be a SIP proxy or thePNC MUST includePDS. It then transmits the request, after establishing a TLS session if required. If obtained via a SIPIdentity header as defined in [RFC4474] within profile notifications sent in responseproxy, the Request-URI is used to route it tolocal-network profile enrollment, unless an integrity-protected channel exists (for example, using S/MIME) *adevice receiving profile notifications for local-network profiles MUST verify thePDS (via an authoritative SIPIdentity header, unless transmitted overproxy, if required). When apreviously established authenticated, integrity-protected channel. IfPDS receives theheader verification fails,enrollment request, it can either challenge thedevice MUST not usepresented identity (if any) or admit the enrollment. Authorization then decides if theprovided profile and treat it as a local-network profile enrollment failure and take measures such asenrollmentretries deviceis accepted. If accepted, the PDS sends an initial notification that contains either: profile data or content indirection information. Thedeviceprofileis expected to containdata can contain information specific to an entity (such as the deviceidentity (AOR) being presented in the request. The presented identityor a user) and maybe auto-generated (for example, based on its hardware identitycontain sensitive information (such asallowed in section Section 5.1.1.2.1) or obtained via configuration. This identitycredentials). Compromise of such data can lead to threats such as impersonation attacks (establishing rogue sessions), theft of service (if services are obtainable), andassociated credentials havezombie attacks. Even if thefollowing considerations: * credentials can beprofile data is providedvia out-of-band mechanismsusing content indirection, PCC information within the notification can lead to threats such aspre-configuration or user interface * credentials may not be present, but obtained viadenial of service attacks (rogue devices bombard theinitial device profile, if allowed byPCC with requests for a specific profile) and attempts to modify erroneous data onto theService Provider * device may usePCC (since theuser's AORlocation andassociated credentialsformat may be known). It is also important forobtaining the device profile IftheAOR presented indeviceprofile enrollment is known by the PNC,to ensure thefollowing requirements are presented: *authenticity of the PNCMUST authenticatesince impersonation of theAOR presented for enrollment usingSIPDigest 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 provideservice provider can lead to Denial of Service, Man-in-the- Middle attacks, etc. Profile content retrieval allows agenericdeviceprofile for minimal services (for example, emergency calls in a telephony deployment, see [I-D.ietf-ecrit-phonebcp]) * if theto retrieve profile data from a PCC. This communication isprovided in the enrollment notificaiton, the PNC MUST transmit it over an integrity-protected, confidential communications channelaccomplished using one of many profile delivery protocols or frameworks, such asTLS If the AOR presentedHTTP or HTTPS as specified indevicethis document. However, since the profileenrollmentdata returned isnot known by the PNC,subject to thefollowing requirements are presented: *same considerations as that sent via profile notification, thePNC MUSTsame threats exist. Profile-specific considerations follow. 10.1. Local-network profile A local network may or may notprovide any sensitive information(e.g., home router) support local- network profiles as specified in this framework. Even if supported, the PDS may only be configured with a generic local-network profiledata * thethat is provided to every deviceMUST transmit the request over an integrity- protected SIP communications channel. If none exists,capable of accessing thedevice MUST establishnetwork. Such aTLS connection with the PNC and verify the PNC's certificate. If the PNCPDS may not implement any authenticationfailsrequirements ora secure communications channel cannot be established,TLS. Alternatively, certain deployments may require the entities - deviceMUST treat it as a device profile enrollment failureandtake measures such as retry enrollment user profile The user profile is expectedthe PDS - tocontain data specificmutually authenticate prior totheprofile enrollment. Such networks may pre-configure useridentity (AOR) being presented in the request. This identity is expectedidentities tobe known inthenetworkdevices andassociated with credentials. Thus, the following requirements are presented: * the device MUST transmitallow user-specific local-network profiles. In such networks therequest over an integrity- protected SIP communications channel. If none exists,PDS will contain X.509 certificates and support TLS, and thedevice MUST establish a TLS connectiondevices are pre-configured withthe PNCuser identities, credentials andverify the PNC's certificate.implement TLS. This framework supports both use cases and variations in-between. However, devices obtaining local-network profiles from an unauthenticated PDS are cautioned against potential MiM or PDS impersonation attacks. This framework requires that a device reject sensitive data, such as credentials, from unauthenticated local- network sources (exceptions are noted). It also prohibits devices from responding to authentication challenges from unauthenticated PDSs. Responding to unauthenticated challenges allows for dictionary attacks that can reveal weak passwords. If deployments prefer devices to obtain profiles only from pre- configured domains (e.g., partner networks), they MAY require such devices to establish TLS prior to obtaining thePNC authentication fails or a secure communications channel cannot be established,local-network profile. The use of SIP Identity is useful in cases when TLS is not used but the deviceMUST treat this asstill obtains auserprofileenrollment failure and take measures such as retry enrollment * the PNC MUST authenticate(e.g., theAOR presented for enrollment using SIP Digest authentication, unless a previously established mutually authenticated channel exists (for example, using TLS). Iflocal-network profile). In such cases theuser authentication fails,device provider, or thePNC MUST not provideuser, can use therequested user-specific information. It MAY provide minimal profile information (such as connectionSIP Identity header toa customer support webpage) * ifverify theprofile data is provided insource of theenrollment notificaiton,local-network profile. However, thePNC MUST transmit it over an integrity-protected, confidential communications channel such as TLS 9.2. Profile Content Retrieval This frameworkpresence of the header does notmandate specific profile delivery frameworks, but presents security requirements for profile content retrieval using content indirection. Givenguarantee thenaturevalidity of theprofiles,data. It verifies therequirements are as follows: o devicessource andPCCs compliant with this framework MUST implement HTTP Digest authentication as specified in [RFC2617]; this is used wheneverconfirms data integrity, but the data obtained from anauthentication challenge is initiated using HTTP based protocols specifiedundesired source may still be invalid (e.g., it can be invalid or contain malicious content). 10.2. Device profile Device profiles deal with device-specific configuration. They may be provided to unknown devices that are attempting to obtaining profiles forinteroperability o a PCC complyingpurposes of trials and self-subscription to SIP services (not to be confused withthis framework MUST implement HTTPS [RFC2818]; this is used when there[RFC3265]), emergency services ([I-D.ietf-ecrit-phonebcp]), or to devices that are known by the PDS. Devices that are not aware of any device providers (i.e., noexisting integrity- protected communication channels o a PCC complying with this framework MUST containcached or configured information) will have to discover aX.509 certificate. This certificate MUST contain the PNC's Fully Qualified Domain NamePDS in the'SubjectAltName', establishingnetwork they connect to. In such a case thePNC asdiscovered information may lead them to ahostPDS that provides enough profile data to enable device operation. This configuration can also provide a user AoR that can be used in theService Provider's domain The following general requirement applieslocal-network and credentials (temporary or long-term) that will be used for future communication with the network. This may enable the device toall profile types: ocommunicate with a deviceMUST request profile content retrieval over an integrity protected channel such as HTTPS. If one does not existprovider who allows for self-subscription (e.g., web interface, interactive voice response orcannot be established, thencustomer service representative). It may also allow the deviceMUST treat this asaprofile content retrieval failurechoice of device providers andtake measuresallow the end-user to choose one. It is to be noted that suchas profile content retrieval retries or indevices are at thecasemercy ofretry exhaustion, try enrollment The following profile-specific usage requirementsthe network they connect to initially. If they arepresented local-network profile *initialized in aPCC MUST challengerogue network, or get hijacked by aprofile content retrieval request ifrogue PDS, theprofile data contains user-specific information; this challenge is againstend-user may be left without desired device operation, or worse unwanted operation. To mitigate such factors the device provider may communicate temporary credentials (PINs that can be entered via an interface) or permanent credentials (e.g., auser's AOR, known byUSB device) to the end-user for connectivity. If such methods are used thePCC andlarge-entropy credentials MUST be used, or quickly replaced with such, to minimize the impact of dictionary attacks. Future enhancements to this framework may specify device*capabilities that allow for mutual authentication without pre-configuration (e.g., X.509 certificates using PKI). Once aPCC MAY challengedevice is associated with aprofile content retrieval request even ifdevice provider (either dynamically or via pre-configuration using a user interface or prior to distribution), the device profiledata contains user-specific information; this challengeisagainst a user's AOR, if providedvital to device operation. This is because the device profile* a PCC MUST authenticate a profile content retrieval request ifcan contain important operational information such as users that are to be allowed access (white-list or black-list), user credentials (if required) and other sensitive information. Thus, it is also necessary to ensure that theAOR presenteddevice profile isknown. Ifnot obtained via an unauthenticated source or tampered during transit. Thus theauthentication fails,framework requires that devices supporting any sensitive device profiles establish next-hop authenticated TLS connections prior to device enrollment. However, given thePCC MUST not provide device-specific information. In such a scenario,importance of thePCC MAY still provide a genericdevice profile it also allows forminimal services (for example, emergency calls in a telephony deployment, see [I-D.ietf-ecrit-phonebcp]) user profile * a PCC MUST authenticate aprofilecontent retrieval request. If the user authentication fails,requests in cases where thePNC MUSTPDS does notprovide the requested user-specific information.implement TLS. ItMAY provide minimal profile information (such as connectionalso allows the PDSs toa customer support webpage) 9.3. Profile Change Operation Changesperform authentication without requiring TLS. However, this leaves the communication open toprofiles willMiM attacks and SHOULD be avoided. Additionally any credential used SHOULD be of sufficiently large- entropy to prevent dictionary attacks. Devices SHOULD use the 'cnonce' parameter ([RFC2617]) to thwart "offline" dictionary attacks. 10.3. User profile Devices can onlybe made by authorized entities and requires mutual authentication. The following requirementsrequest user profiles for users that arepresented: o a PCC complying with this framework MUST containknown by aX.509 certificate. This certificate MUST contain the PNC's Fully Qualified Domain NameSIP service provider. Thus, PDSs are prohibited from accepting user profile enrollment requests for users that are unknown in the'SubjectAltName', establishingnetwork. If thePNC asuser AoR is ahost inSIPS URI then theService Provider's domain.device is required to establish a next-hop authenticated TLS session. Thismay be the same, or different, from the certificate usedframework RECOMMENDS this forprofile content retrieval o an entity thatprofiles with sensitive data. If it isallowed to make updates MUST containaAOR thatSIP URI, then the device isknownstill recommended to attempt TLS establishment to ensure protection against rogue PDSs. A PDS is always recommended to authenticate thenetwork and the requirements for making changesuser AoR prior to profile enrollment. The considerations are the same as that forusera device profilecontent retrieval,withthe authorized entity playing the role of apre-configured user10.AoR. 11. AcknowledgementsMany thanks toThe author appreciates all 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 final revisions of this document were a product of design team discussions. The editorwould likewishes to extendaspecialthanks to the experts who contributedappreciation to therestructuringfollowing design team members for their numerous reviews andrevisions as proposed by the SIPPING WG, specifically Keith Dragespecific contributions to various sections: Josh Littlefield fromLucent (restructuring proposal),Cisco (Executive Summary, Overview, Section 6), Peter Blatherwick from Mitel(who also contributed to the Overview(Section 6), Cullen Jennings (Security), Sam Ganesan (Section 6) andIntroduction sections), Josh Littlefield from Cisco (examplesMary Barnes (layout, Section 6). The following design team members are thanked for numerous reviews anddiagram suggestions), Alvin Jiang of Engin,general contributions: Martin Dolly fromAT&T,AT&T Labs, Jason Fischl fromCounterpath,Counterpath, Alvin Jiang of Engin and Francois Audet from Nortel. The following SIPPING WG members are thanked for numerours reviews, comments and recommendations: John Elwell from Siemens, Donald Lukacs fromTelcordiaTelcordia, 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 Petersonand Cisco)from Neustar) for facilitating discussions,and forreviews and contributions.11.The editor would also like to extend a special thanks to the comments and recommendations provided by the SIPPING WG, specifically Keith Drage from Lucent (restructuring proposal). 12. Change History [[RFC Editor: Please remove this entire section upon publication as an RFC.]]11.1.12.1. Changes from draft-ietf-sipping-config-framework-11.txt The following are the major changes that have been incorporated into this I-D. o Incorporated the decisions taken at the last IETF: added an executive summary section; removed 'device-id' and replaced with 'sip.instance' o Removed the HTTPS bootstrapping section (this could be a different I-D) o Added IANA registry for the 'profile-type' parameter (comment from Adam Roach) o Incorporated comments from Cullen Jennings, John Elwell, and design team reviews o Revised section 6 to make it flow better o Removed 'Profile Change Modification' from the document o Revised the security section. 12.2. 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'sAOR,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! 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 sections11.2.12.3. 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,(e.g., 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.11.3.12.4. Changes from draft-ietf-sipping-config-framework-08.txt The Request URI for profile-type=localnet now SHOULD not have a user part to make routing easier. The From field SHOULD now contain the device id so that device tracking can still be done. Described the concept of profile-type as a filter and added normative text requiring 404 for profile types not provided. Moved "application" profile type to draft-ietf-sipping-xcap-config-01. The "application" value for the profile-type parameter will also be used as a requirement that XCAP be supported. Fixed text on certificate validation. Added new HTTP header: Event to IANA section and clean up the IANA section. Added diagram for Service Provider use case schenario. Added clarification for HTTP Event header. Added clarification of subscriber handling of NOTIFY with no body.11.4.12.5. 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.11.5.12.6. 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 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!11.6.12.7. 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.11.7.12.8. 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.11.8.12.9. Changes from draft-ietf-sipping-config-framework-03.txt Incorporated changes to better support the requirements for the use of this event package with XCAP and SIMPLE so that we can have one package (i.e. simple-xcap-diff now defines a content type not a package). Added an additional profile type: "application". Added document and app-id Event header parameters in support of the application profile. Define a loose high level data model or relationship between the four profile types. Tried to edit and fix the confusing and ambiguous sections related to URI formation and discovery for the different profile types. Better describe the importance of uniqueness for the instance id which is used in the user part of the device URI.11.9.12.10. 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.11.10.12.11. 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.11.11.12.12. 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 Three high level security approaches are now specified.11.12.12.13. 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.11.13.12.14. Changes from draft-petrie-sip-config-framework-01.txt Changed the name as this belongs in the SIPPING work group. Minor edits11.14.12.15. 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.12.13. References12.1.13.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2434] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 2434, October 1998. [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. [RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S., Leach, P., Luotonen, A., and L. Stewart, "HTTP Authentication: Basic and Digest Access Authentication", RFC 2617, June 1999. [RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000. [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, June 2002. [RFC3263] Rosenberg, J. and H. Schulzrinne, "Session Initiation Protocol (SIP): Locating SIP Servers", RFC 3263, June 2002. [RFC3265] Roach, A., "Session Initiation Protocol (SIP)-Specific Event Notification", RFC 3265, June 2002.[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. [RFC4346] Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS) Protocol Version 1.1", RFC 4346, April 2006. [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.[RFC4704] Volz, B., "The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Client Fully Qualified Domain Name (FQDN) Option", RFC 4704, October 2006. 13.2. 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-12draft-ietf-ecrit-phonebcp-01 (work in progress),October 2006. [I-D.ietf-simple-xcap-diff] Rosenberg, J., "An Extensible Markup Language (XML) Document Format for Indicating A ChangeMarch 2007. [I-D.ietf-sip-outbound] Jennings, C. and R. Mahy, "Managing Client Initiated Connections inXML Configuration Accessthe Session Initiation Protocol(XCAP) Resources", draft-ietf-simple-xcap-diff-04(SIP)", draft-ietf-sip-outbound-08 (work in progress),October 2006.March 2007. [RFC0959] Postel, J. and J. Reynolds, "File Transfer Protocol", STD 9, RFC 959, October 1985.[RFC2131][RFC2132] Alexander, S. and R. Droms,R., "Dynamic Host Configuration Protocol","DHCP Options and BOOTP Vendor Extensions", RFC2131,2132, 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. [RFC4825] Rosenberg, J., "The Extensible Markup Language (XML) Configuration Access Protocol (XCAP)", RFC 4825, May 2007. 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/ Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. 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