1、 International Telecommunication Union ITU-T J.368TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (06/2008) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS IPCablecom IPCablecom2 quality of service specification Recommendation ITU-T J.368 Rec. IT
2、U-T J.368 (06/2008) i Recommendation ITU-T J.368 IPCablecom2 quality of service specification Summary Recommendation ITU-T J.368 defines how the QoS capabilities of IPCablecom2 Multimedia are integrated with the Policy and Charging Control (PCC) architecture specified in the IPCablecom2 control plan
3、e architecture. Source Recommendation ITU-T J.368 was approved on 13 June 2008 by ITU-T Study Group 9 (2005-2008) under ITU-T Recommendation A.8 procedure. ii Rec. ITU-T J.368 (06/2008) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of
4、telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization 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 te
5、lecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets 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 th
6、e procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, 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
7、a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the Recommendation is achieved when all
8、of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and 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 RIGH
9、TS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve 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
10、 members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, 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 m
11、ay not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2009 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
12、.368 (06/2008) iii CONTENTS Page 1 Scope 1 2 References. 1 2.1 Normative References 1 2.2 Informative References 1 2.3 Reference Acquisition 2 3 Terms and Definitions 2 4 Abbreviations, acronyms and conventions. 2 4.1 Abbreviations and Acronyms . 2 4.2 Conventions 3 5 Overview 3 5.1 QoS Architecture
13、 Reference Model . 4 5.2 Functional Components 5 5.3 Protocol Interfaces and Reference Points. 7 5.4 Application of QoS Policy within IPCablecom2 7 6 IPCablecom2 support of 3GPP Rx reference point 8 6.1 P-CSCF. 8 6.2 IPCablecom2 Application Manager . 10 7 Parameter Mapping. 12 7.1 Mapping AA-Request
14、s to Gate-Set 13 7.2 Mapping Gate-Set-Ack to AA-Answers 17 Rec. ITU-T J.368 (06/2008) 1 Recommendation ITU-T J.368 IPCablecom2 quality of service specification 1 Scope This Recommendation defines the requirements and functionality needed to support Quality of Service (QoS) within the IPCablecom2 Arc
15、hitecture It is an important 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 fo
16、r wireless, wireline, 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. NOTE The structure and content of this Recommendation have been organized for ease
17、 of use by those familiar with the original source material; as such, the usual style of ITU-T recommendations has not been applied. 2 References 2.1 Normative References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute pro
18、visions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendat
19、ions and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. PCMM Recommendation ITU-T J.179, IPCablecom support
20、for multimedia. ETSI TS 29.214 ETSI TS 129.214, Policy and Charging Control over Rx reference point, Release 7, V7.2.0, September 2007. ETSI TS 29.213 ETSI TS 129.213, Policy and Charging Control signalling flows and QoS parameter mapping, Release 7, V7.2.0, September 2007. 2.2 Informative Reference
21、s This Recommendation uses the following informative references. CPD Recommendation ITU-T J.362, IPCablecom2 control point discovery. CODEC-MEDIA Recommendation ITU-T J.361, IPCablecom2 codec and media. TS 23.203 3GPP TS 23.203, Policy and charging control architecture, Release 7, V7.3.0, June 2007.
22、 PKT 24.229 Recommendation ITU-T J.366.4 (2006), IPCablecom2 IP Multimedia Subsystem (IMS): Session Initiation Protocol (SIP) and Session Description Protocol (SDP) Stage 3 specification. TS 29.212 3GPP TS 29.212, Policy and Charging Control over Gx reference point, Release 7, V7.2.0, September 2007
23、. 2 Rec. ITU-T J.368 (06/2008) ICE IETF Internet Draft, Interactive Connectivity Establishment (ICE), A Methodology for Network Address Translator (NAT) Traversal for Offer/Answer Protocols, draft-ietf-mmusic-ice-18.txt, September 2007, work in progress. NAT Recommendation ITU-T J.360, IPCablecom2 a
24、rchitecture framework. 2.3 Reference Acquisition Third Generation Partnership Project (3GPP), Internet: http:/www.3gpp.org Internet Engineering Task Force (IETF), Internet: http:/www.ietf.org/ NOTE Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or
25、 obsoleted by other documents at any time. The list of current Internet-Drafts can be accessed at http:/www.ietf.org/ietf/1id-abstracts.txt. 3 Terms and Definitions This Recommendation defines the following terms: 3.1 DOCSIS: A set of interface specifications for transmitting data over cable televis
26、ion systems in a standard fashion. 3.2 IPCablecom2 application manager (PAM): A specialized Application Manager defined in IPCablecom2, primarily responsible for determining QoS resources needed for a session. 3.3 network enforced preconditions: A method of ensuring that necessary QoS resources are
27、available before alerting the called user by withholding SIP messages within the network until the results of necessary policy interactions are known. This capability is independent from the use by the UE of the similarly named QoS Preconditions capability defined by RFCs 3312 and 3313. 3.4 policy s
28、erver: A system that primarily acts as an intermediary between Application Manager(s) and CMTS(s). It applies network policies to Application Manager requests and proxies messages between the Application Manager and CMTS. 4 Abbreviations, acronyms and conventions 4.1 Abbreviations and Acronyms This
29、Recommendation uses the following abbreviations and acronyms: AF Application Function AMID Application Manager Identifier BCID Billing Correlation ID CM DOCSIS-compliant Cable Modem CMTS Cable Modem Termination System CSCF Call Session Control Function DOCSIS Data Over Cable Service Interface Specif
30、ications DSCP Differentiated Services Code Point IP-CAN IP Connectivity Access Network NAT Network Address Translation PAM IPCablecom2 Application Manager PCC Policy and Charging Control Rec. ITU-T J.368 (06/2008) 3 PCEF Policy and Charging Enforcement Function PCRF Policy and Charging Rules Functio
31、n P-CSCF Proxy CSCF PS Policy Server SDP Session Description Protocol SIP Session Initiation Protocol SPR Subscription Profile Repository UE User Equipment 4.2 Conventions Throughout this Recommendation, the words that are used to define the significance of particular requirements are capitalized. T
32、hese words are: “MUST“ This word means that the item is an absolute requirement of this Recommendation. “MUST NOT“ This phrase means that the item is an absolute prohibition of this Recommendation. “SHOULD“ This word means that there may exist valid reasons in particular circumstances to ignore this
33、 item, but the full implications should be understood and the case carefully weighed before choosing a different course. “SHOULD NOT“ This phrase means that there may exist valid reasons in particular circumstances when the listed behaviour is acceptable or even useful, but the full implications sho
34、uld be understood and the case carefully weighed before implementing any behaviour described with this label. “MAY“ This word means that this item is truly optional. One vendor may choose to include the item because a particular marketplace requires it or because it enhances the product, for example
35、; another vendor may omit the same item. 5 Overview The primary focus of this Recommendation is to define how the QoS capabilities of IPCablecom2 Multimedia are integrated with the Policy and Charging Control (PCC) architecture defined by the 3rd Generation Partnership Project (3GPP) for its IP Mult
36、imedia Subsystem (IMS) which forms the basis of the IPCablecom2 control plane architecture. In addition to describing how the PCC architecture is realized in an IPCablecom2 network and providing an overview of network elements which make up the architecture, this Recommendation defines detailed requ
37、irements for passing session level information by the Proxy Call Session Control Function (P-CSCF) and the use of this information by the IPCablecom2 Application Manager (PAM) to provide QoS in the DOCSIS access network. The QoS and event messaging capabilities of IPCablecom2 Multimedia are integrat
38、ed into the IMS based IPCablecom2 architecture through the Policy and Charging Control (PCC) capability introduced in 3GPP release 7. PCC represents the evolution of the separate policy and charging control mechanisms defined in earlier 3GPP releases while incorporating additional requirements, such
39、 as support for policy push, indication of session priority, more detailed session description information, and support for separate reservation and commitment of resources which allow PCC to support various access technologies. 4 Rec. ITU-T J.368 (06/2008) 5.1 QoS Architecture Reference Model The I
40、PCablecom2 QoS architecture reference model, illustrated in Figure 1, uses the generic IPCablecom2 Multimedia components including the Policy Server, CMTS, and Cable Modem. The IPCablecom2 Application Manager (PAM) is a specialized Application Manager that receives session-level QoS requests via Rx
41、from the P-CSCF and creates and manages the IPCablecom2 Multimedia Gates for each flow in the session using the IPCablecom2 Multimedia pkt-mm-3 interface. The IPCablecom2 Application Manager interacts with the P-CSCF via Rx for sessions involving UEs in the IPCablecom2 Multimedia network just as the
42、 PCRF does for sessions involving UEs in the GPRS network. Figure 1 illustrates how the IPCablecom2 Multimedia QoS architecture, used for UEs accessing services via a DOCSIS network, integrates into the 3GPP Policy and Charging Control architecture. Policy ServerCMTSCMUEIPCablecom Application Manage
43、rP-CSCFpkt-mm-1pkt-mm-2Rxpkt-qos-2pkt-mm-3GmPCRFFigure 1 QoS Architecture Reference Model Reference points pkt-mm-1 through pkt-mm-3 are defined by IPCablecom2 Multimedia. Reference point pkt-qos-2 is defined by IPCablecom2. Reference points Gm and Rx are defined by 3GPP. Table 1 describes these int
44、erfaces briefly. Rec. ITU-T J.368 (06/2008) 5 Table 1 QoS Reference Points Reference Point IPCablecom2 Network Elements Reference Point Description pkt-mm-1 CMTS CM The CMTS uses DOCSIS-defined DSX signalling to instruct the CM to set up, teardown, or change a DOCSIS service flow in order to satisfy
45、 a QoS request. pkt-mm-2 Policy Server CMTS The interface supports proxy QoS requests on behalf of a UE. This interface is fundamental to the policy-management framework. It controls policy decisions, which are pushed by the Policy Server (PS) onto the CMTS, and is defined by PCMM. In some scenarios
46、, this interface is also used to inform the PS of changes in the status of QoS resources. pkt-mm-3 PAM PS This interface allows the IPCablecom2 Application Manager (PAM), a specialized Application Manager defined in IPCablecom2, to request that the PS install a policy decision on the CMTS on behalf
47、of the UE, and is defined by PCMM. This interface may also be used to inform the PAM of changes in the status of QoS resources. Gm UE P-CSCF Allows the UE to communicate with the P-CSCF for registration and session control. This reference point is SIP-based and is described in PKT 24.229. Rx P-CSCF
48、PAM The Rx interface is used for session-based policy set-up information exchange between the P-CSCF and the IPCablecom2 Application Manager. Note that this is the same interface that is used between the P-CSCF and the Policy and Charging Rules Function (PCRF) in the case of GPRS access. This interf
49、ace may also be used to inform the P-CSCF of changes in the status of QoS resources. pkt-qos-2 Policy Server CMTS The Policy Server uses the Control Point Discovery Protocol to determine the serving CMTS in the network for a given UE. This reference point is based on IPCablecom2 specification CPD. 5.2 Functional Components In this clause, additional detail is provided on the P-CSCF, IPCablecom2 Application Manager, Policy Server, and CMTS and their roles as related to the QoS architecture. 5.2.1 P-CSCF The P-CSCF fulfils the
