1、 International Telecommunication Union ITU-T J.366.3TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (08/2010) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS IPCablecom IPCablecom2 IP Multimedia Subsystem (IMS): Stage 2 Specification Recommendati
2、on ITU-T J.366.3 Rec. ITU-T J.366.3 (08/2010) i Recommendation ITU-T J.366.3 IPCablecom2 IP Multimedia Subsystem (IMS): Stage 2 specification Summary Recommendation ITU-T J.366.3 defines the stage-2 service description for the IP Multimedia Core Network Subsystem (IMS), which includes the elements n
3、ecessary to support IP multimedia (IM) services. Recommendation ITU-T I.130 describes a three-stage method for the characterization of telecommunication services, and Recommendation ITU-T Q.65 defines Stage 2 of the method. The Third Generation Partnership Project (3GPP) has developed the specificat
4、ion in a form optimized for the wireless environment. Recommendation ITU-T J.366.3 references the ETSI version of the 3GPP specification (ETSI TS 123 228 V6.12.0 (2005-12) and specifies only the modifications necessary to optimize it for the cable environment. History Edition Recommendation Approval
5、 Study Group 1.0 ITU-T J.366.3 2010-08-29 9 ii Rec. ITU-T J.366.3 (08/2010) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardizati
6、on Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meet
7、s every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts p
8、urview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is v
9、oluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ an
10、d the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may inv
11、olve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Rec
12、ommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database
13、at http:/www.itu.int/ITU-T/ipr/. ITU 2010 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T J.366.3 (08/2010) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3
14、.2 Terms defined in this Recommendation . 1 4 Abbreviations and acronyms 1 5 Conventions 1 6 Modifications to ETSI TS 123 228 2 Rec. ITU-T J.366.3 (08/2010) 1 Recommendation ITU-T J.366.3 IPCablecom2 IP Multimedia Subsystem (IMS): Stage 2 Specification 1 Scope This Recommendation defines the stage-2
15、 service description for the IP Multimedia Core Network Subsystem (IMS), which includes the elements necessary to support IP Multimedia (IM) services. ITU-T I.130 describes a three-stage method for the characterization of telecommunication services, and ITU-T Q.65 defines stage-2 of the method. The
16、Third Generation Partnership Project (3GPP) has developed the specification in a form optimized for the wireless environment. This Recommendation references the ETSI version of the 3GPP specification and specifies only the modifications necessary to optimize it for the cable environment. It is an im
17、portant objective of this work that interoperability between IPCablecom 2.0 and 3GPP IMS is provided. IPCablecom 2.0 is based upon 3GPP IMS, but includes additional functionality necessary to meet the requirements of cable operators. Recognizing developing converged solutions for wireless, wireline,
18、 and cable, it is expected that further development of IPCablecom 2.0 will continue to monitor and contribute to IMS developments in 3GPP, with the aim of alignment of 3GPP IMS and IPCablecom 2.0. Because ITU-T Recommendation indicates modifications from the ETSI specification ETSI TS 123 228, the s
19、tructure of the Recommendation does not follow normal ITU-T practice, to ease the task of the reader to correlate the two documents. The modifications are shown in clause 6. 2 References ITU-T I.130 Recommendation ITU-T I.130 (1988), Method for the characterization of telecommunication services supp
20、orted by an ISDN and network capabilities of an ISDN. ITU-T Q.65 Recommendation ITU-T Q.65 (2000), The unified functional methodology for the characterization of services and network capabilities including alternative object-oriented techniques. ETSI TS 123 228 ETSI TS 123 228 V6.12.0 (2005), IP Mul
21、timedia Subsystem (IMS); Stage 2. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the terms defined in ETSI TS 123 228. 3.2 Terms defined in this Recommendation None. 4 Abbreviations and acronyms This Recommendation uses the abbreviations provided in ETSI TS 123 228. 5 Conventions
22、 This Recommendation uses the conventions provided in ETSI TS 123 228. 2 Rec. ITU-T J.366.3 (08/2010) 6 Modifications to ETSI TS 123 228 Modifications introduced by this Recommendation are shown in revision marks. Unchanged text is replaced by ellipsis (). Some parts of unchanged text (section numbe
23、rs, etc.) may be kept to indicate the correct insertion points. 2 References 3 Recommendation ITU-T Q.65: “Methodology Stage 2 of the method for the characterisation of services supported by an ISDN“. 4 Recommendation ITU-T I.130: “Method for the characterization of telecommunication services suppor
24、ted by an ISDN and network capabilities of an ISDN“. 3 Recommendation ITU-T Q.65 (2000), The unified functional methodology for the characterization of services and network capabilities including alternative object-oriented techniques. 4 Recommendation ITU-T I.130 (1988), Method for the characteriza
25、tion of telecommunication services supported by an ISDN and network capabilities of an ISDN. 45 Recommendation ITU-T J.360 (2006), Appendix V; IPCablecom2 NAT and firewall traversal overview. 46 Recommendation ITU-T J.360 (2006), Appendix II; Quality of service architecture technical overview. 47 IE
26、TF RFC 5627 (2009), Obtaining and Using Globally Routable User Agent URIs (GRUUs) in the Session Initiation Protocol (SIP). 48 IETF RFC 5628 (2009), Registration Event Package Extension for Session Initiation Protocol (SIP) Globally Routable User Agent URIs (GRUUs). 49 Recommendation ITU-T J.365 (20
27、06), IPCablecom2 application manager interface. 3 Definitions, symbols and abbreviations 3.3 Abbreviations GMLC Gateway Mobile Location Centre GUP Generic User Profile GRUU Globally Routable User Agent URI TrGW Translation Gateway Rec. ITU-T J.366.3 (08/2010) 3 TSG Technical Specification Group 4.3.
28、3.2 Public user identities Public User Identities are not authenticated by the network during registration. Public User Identities may be used to identify the users information within the HSS (for example during mobile terminated session set-up). 4.3.3.2a Globally Routable User Agent URIs (GRUUs) Ea
29、ch Public User Identity may have one or more Globally Routable User Agent URIs (GRUUs). Each GRUU is associated with one Public User Identity and one UE. The assignment and use of GRUUs conforms to the specifications of IETF RFC 5627 47. For purposes of establishing the association, a UE is identifi
30、ed by an Instance ID. An Instance ID is only assigned to one UE at any given time. The GRUU serves as a URI that may be used from any domain and will route only to one UE possessing the associated Instance ID, and only if the UE is at that time registered to the associated Public User Identity. GRUU
31、s are assigned by the S-CSCF. Requests addressed to a GRUU are routed for termination processing to the S-CSCF responsible for the Public User Identity to which the GRUU is associated. When doing termination processing for a request addressed to a GRUU, an S-CSCF shall use the IMS service profile fo
32、r the Public User Identity to which the GRUU is associated. The services applied to a request addressed to a GRUU may differ from those applied to a request addressed to the associated Public User Identity. This shall be controlled by conditional specifications in the IMS service profile. 4.3.3.4 Re
33、lationship of Private and Public User Identities All Service Profiles of a user shall be stored in the same HSS, even if the user has one or more shared Public User Identities. 4.3.3.5 Relationship of Public User Identities, GRUUs and UEs Each GRUU is associated with one Public User Identity and one
34、 UE. This relationship is depicted in Figure 4.6a. If a UE registers (explicitly or implicitly) with multiple Public User Identities, a separate GRUU is associated with each. If different UEs register with the same Public User Identity, a separate GRUU is associated with each. 4 Rec. ITU-T J.366.3 (
35、08/2010) Private useridentity-1Private useridentity-2Public useridentity-1Public useridentity-3Public useridentity-2GRUU-1GRUU-4GRUU-3GRUU-2UE-1UE-2J.366.3(10)_F4.6aFigure 4.6a The relationship of Public User Identities, GRUUs, and UEs 4.6.1 Proxy-CSCF The Proxy-CSCF (P-CSCF) is the first contact po
36、int within the IM CN subsystem. Its address is discovered by UEs using the mechanism described in section “Procedures related to Local CSCF Discovery“. The P-CSCF behaves like a Proxy (as defined in RFC 3261 12 or subsequent versions), i.e., it accepts requests and services them internally or forwar
37、ds them on. The P-CSCF shall not modify the Request URI in the SIP INVITE message. The P-CSCF may behave as a User Agent (as defined in the RFC 3261 12 or subsequent versions), i.e., in abnormal conditions it may terminate and independently generate SIP transactions. The Policy Decision Function (PD
38、F) may be a logical entity of the P-CSCF or a separate physical node. If the PDF is implemented in a separate physical node, the interface between the PDF and the P-CSCF is the Gq interface standardised in TS 23.207 9. When providing service to a UE residing in a cable-based access network, the inte
39、rface between the IPCablecom Application Manager and the P-CSCF is defined by the IPCablecom Application Manager Interface specification 49. The functions performed by the P-CSCF are: 4.6.3 Serving-CSCF The Serving-CSCF (S-CSCF) performs the session control services for the UE. It maintains a sessio
40、n state as needed by the network operator for support of the services. Within an operators network, different S-CSCFs may have different functionalities. The functions performed by the S-CSCF during a session are: Registration May behave as a Registrar as defined in RFC 3261 12 or subsequent version
41、s, i.e., it accepts registration requests and makes its information available through the location server (e.g., HSS). When a registration request includes an instance id with the contact being registered, the S-CSCF assigns a unique GRUU to the combination of Public User Identity and Instance ID. I
42、f a registration request indicates support for GRUU, the S-CSCF will return the GRUU assigned to each currently registered Instance ID. Rec. ITU-T J.366.3 (08/2010) 5 Notify subscribers about registration changes, including the GRUUs assigned to registered instances. Session-related and session-unre
43、lated flows 4.11 Relationship to 3GPP Generic User Profile (GUP) It shall be possible to apply the mechanisms and format of the 3GPP Generic User Profile (GUP) to IM CN Subsystem user related data. The 3GPP Generic User Profile (GUP) is described in TS 23.240 31. 4.12 Network Address Translation tra
44、versal in access network It shall be possible to support the scenario where a NAT(-PT)/NAPT(-PT) residing between the IMS functionality in the UE and the P-CSCF has to be traversed for IMS communication. This shall include at least the types of NATs that are commonly deployed. The NAT traversal meth
45、odology is based on IETF best practices and described in 45. NOTE 1 The UE may be one piece of equipment, or it may be a network of elements located on end-users physical premises. 5.4.4 Requirements for IP multi-media session control 5. The IP-Connectivity Access Network service shall should be abl
46、e to notify the IP multimedia session control when the IP-Connectivity Access Network service has either modified or suspended or released the bearer(s) of a user associated with a session (because, e.g., the user is no longer reachable). 5.4.7.0 General At IP-CAN bearer activation the user shall ha
47、ve access to either IP-CAN services without service-based local policy, or IP-CAN services with service-based local policy. It is operator choice whether to offer both or only one of these alternatives for accessing the IM Subsystem. When using IP-CAN without service-based local policy, the bearer i
48、s established according to the users subscription, local operators IP bearer resource based policy, local operators admission control function and roaming agreements. When using IP-CAN with service-based local policy, Service-Based Local Policy decisions (e.g., authorization and control) are also ap
49、plied to the bearer. The description in this clause and the following subclauses (subclauses 5.4.7.1 5.4.7.7) is applicable for the case when service-based local policy is employed. For the case where IPCablecom Multimedia is employed, the applicable procedures are documented in 46. 6 Rec. ITU-T J.366.3 (08/2010) The IP-Connectivity Access Network contains a Policy Enforcement Function (PEF) that has the capability of policing packet flow into th
