1、 S International Telecommunication Union ITU-T Y.2809TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2011) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Next Generation Networks Generalized mobility Framework of mobility management in the ser
2、vice stratum for next generation networks Recommendation ITU-T Y.2809 ITU-T Y-SERIES RECOMMENDATIONS GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS GLOBAL INFORMATION INFRASTRUCTURE General Y.100Y.199 Services, applications and middleware Y.200Y.299 Network
3、 aspects Y.300Y.399 Interfaces and protocols Y.400Y.499 Numbering, addressing and naming Y.500Y.599 Operation, administration and maintenance Y.600Y.699 Security Y.700Y.799 Performances Y.800Y.899 INTERNET PROTOCOL ASPECTS General Y.1000Y.1099 Services and applications Y.1100Y.1199 Architecture, acc
4、ess, network capabilities and resource management Y.1200Y.1299 Transport Y.1300Y.1399 Interworking Y.1400Y.1499 Quality of service and network performance Y.1500Y.1599 Signalling Y.1600Y.1699 Operation, administration and maintenance Y.1700Y.1799 Charging Y.1800Y.1899 IPTV over NGN Y.1900Y.1999 NEXT
5、 GENERATION NETWORKS Frameworks and functional architecture models Y.2000Y.2099 Quality of Service and performance Y.2100Y.2199 Service aspects: Service capabilities and service architecture Y.2200Y.2249 Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Numbering, naming
6、 and addressing Y.2300Y.2399 Network management Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Smart ubiquitous networks Y.2600Y.2699 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899 Carrier grade open environment Y.2900Y.2999 Future networks Y.3000Y.3099 For further de
7、tails, please refer to the list of ITU-T Recommendations. Rec. ITU-T Y.2809 (11/2011) i Recommendation ITU-T Y.2809 Framework of mobility management in the service stratum for next generation networks Summary Recommendation ITU-T Y.2809 describes the framework of mobility management (MM) in the serv
8、ice stratum for next generation networks (NGNs). This Recommendation identifies the functional architecture of MM in the NGN service stratum, and specifies the procedural information flows for location management and handover control based on the IP multimedia subsystem (IMS). History Edition Recomm
9、endation Approval Study Group 1.0 ITU-T Y.2809 2011-11-29 13 Keywords Framework, mobility management, NGN, service stratum. ii Rec. ITU-T Y.2809 (11/2011) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information
10、 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 telecommunications on a worldwide
11、 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 the procedure laid down in WTSA R
12、esolution 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 a telecommunication administrat
13、ion 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 of these mandatory provisions
14、 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 RIGHTS ITU draws attention to the
15、 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 members or others outside of
16、 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 may not represent the latest i
17、nformation and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2012 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 Y.2809 (11/2011) iii Table of
18、Contents Page 1 Scope 1 2 References. 1 3 Definitions 1 4 Abbreviations and acronyms 1 5 Conventions 2 6 Design considerations . 2 7 Functional architecture for MM in the service stratum 4 7.1 Generic architectural model . 4 7.2 MM functional entities in the service control function 5 7.3 Mappings b
19、etween IMS functions and MM control functions . 6 8 Information flows for IMS-based location management 7 8.1 Location registration and location re-registration 7 8.2 Location query 8 9 Information flows for IMS-based handover control . 10 9.1 Handover by interaction between P-CSCF and S-CSCF . 10 9
20、.2 Handover control by interaction between two neighbouring proxy call session control functional entities (P-CSC-FEs) 12 10 Security considerations . 13 Appendix I Use cases of IMS-based MM with IEEE 802.21 . 14 Appendix II Examples of IMS handover using network agents . 21 II.1 RACF applicability
21、in the IMS handover . 21 II.2 GGSN applicability in the IMS handover 22 Bibliography. 24 iv Rec. ITU-T Y.2809 (11/2011) Introduction This Recommendation describes the framework of mobility management (MM) in the service stratum for NGNs. This work has been motivated by the observation that MM is an
22、essential functionality to provide seamless mobility for NGN users and services. This Recommendation is a part of the MM framework for NGNs. Based on the generic framework of ITU-T Q.1707, the two Recommendations ITU-T Q.1708 and ITU-T Q.1709 have addressed the MM schemes in the NGN transport stratu
23、m, whereas this Recommendation deals with the MM schemes in the NGN service stratum. Rec. ITU-T Y.2809 (11/2011) 1 Recommendation ITU-T Y.2809 Framework of mobility management in the service stratum for next generation networks 1 Scope This Recommendation describes the framework of mobility manageme
24、nt (MM) in the service stratum for next generation networks (NGNs). This Recommendation addresses the issues on terminal mobility based on the IP multimedia subsystem (IMS). This Recommendation first identifies the functional architecture of MM in the NGN service stratum, and then specifies the proc
25、edural information flows for location management and handover control based on the identified functional architecture. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the
26、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 Recommendations and other references listed below.
27、 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. ITU-T Q.1707 Recommendation ITU-T Q.1707/Y.2804 (2008), Generic framework of mobility manag
28、ement for next generation networks. ITU-T Q.1708 Recommendation ITU-T Q.1708/Y.2805 (2008), Framework of location management for NGN. ITU-T Q.1709 Recommendation ITU-T Q.1709/Y.2806 (2008), Framework of handover control for NGN. ITU-T Y.2012 Recommendation ITU-T Y.2012 (2010), Functional requirement
29、s and architecture of next generation networks. ITU-T Y.2091 Recommendation ITU-T Y.2091 (2007), Terms and definitions for next generation networks. ITU-T Y.2701 Recommendation ITU-T Y.2701 (2007), Security requirements for NGN release 1. 3 Definitions This Recommendation uses the terms and definiti
30、ons given in ITU-T Y.2012, ITU-T Y.2091, ITU-T Q.1707, ITU-T Q.1708, and ITU-T Q.1709. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: ABG-FE Access Border Gateway Functional Entity A-MMCF Access Mobility Management Control Function BGF Border Gateway
31、Function CN Correspondent Node 2 Rec. ITU-T Y.2809 (11/2011) CSC-FE Call Session Control Functional Entity EN-FE Edge Node Functional Entity FE Functional Entity GGSN GPRS Gateway Supporting Node HC Handover Control HC-FE Handover Control Functional Entity HSS Home Subscriber Subsystem IBG-FE Interc
32、onnection Border Gateway Functional Entity I-CSC-FE Interrogating Call Session Control Functional Entity IMS Internet Protocol Multimedia Subsystem IP Internet Protocol LM Location Management MIH Media Independent Handover MM Mobility Management MMCF Mobility Management Control Function MN Mobile No
33、de NGN Next Generation Network P-CSC-FE Proxy Call Session Control Functional Entity RACF Resource Admission Control Function SAA-FE Service Authentication Authorization Functional Entity SCF Service Control Function S-CSC-FE Serving Call Session Control Functional Entity SDP Session Description Pro
34、tocol S-HC-FE Handover Control Functional Entity in the Service Stratum SIP Session Initiation Protocol SUP-FE Service User Profile Functional Entity UE User Equipment 5 Conventions None. 6 Design considerations This Recommendation considers mobility management (MM) in the service stratum of NGNs. I
35、n the network, a user or a user equipment (UE) may change its IP address by movement and thus the user may experience service disruption and session discontinuity. This Recommendation deals with the MM schemes or protocols that can be used to provide seamless services and session continuity against
36、the movement of users. To provide seamless mobility, the link-layer information on the concerned access links might be used in the MM schemes, as shown in the IEEE 802.21 media independent handover (MIH). In this fashion, the so-called cross-layer optimization tasks may need Rec. ITU-T Y.2809 (11/20
37、11) 3 to be taken to provide seamless mobility. However, the details of a specific link-layer technology are outside the scope of this Recommendation. It is noted that the IP multimedia subsystem (IMS) platform can typically be used to support a variety of multimedia services. b-ITU-T F.700 gives a
38、generic model of multimedia service architecture. Multimedia services are built up by combining communication tasks and organizing their interaction. A communication task is considered as a functional entity of a multimedia service, which performs its communication features. Each communication task
39、handles a set of media components in a synchronized way, in order to convey and control information types such as audio or video. Media components are individual (mono-media) components, which handle functions related to each independent medium such as capture, coding and presentation. With regard t
40、o communication tasks, b-ITU-T F.700 mentions conversing, conferencing, distributing, sending, receiving and collecting. It shall be noted that this list of communication tasks can be extended by new tasks or by the refinement of given tasks. Audio, video, text, graphics and data are identified on t
41、he level of media components. Y.2809(11)_F01MandatoryOptionalGeneric multimedia serviceCommunicationTask ACommunicationTask BMediacomponent 2Mediacomponent 3Mediacomponent 4Mediacomponent 1Figure 1 Reference model of generic multimedia services b-ITU-T F.700 Figure 1 shows the relationship among mul
42、timedia services, communication tasks and media components. Communication tasks and media components will form the basic set of a specific multimedia service. For example, by the used media components, the multimedia conversational services can be further divided into: videophone service, with audio
43、 and moving pictures and optionally various types of data; voice and data services, with audio and various types of data; text telephony, with real time text, optionally combined with audio; total conversation service, with moving pictures, real time text and audio. In general, the MM schemes for mo
44、bility support in NGNs can be classified into the network layer MM (in the transport stratum) and the application layer MM (in the service stratum). The MM issues in the network layer or in the transport stratum are addressed in ITU-T Q.1708 and ITU-T Q.1709. This Recommendation focuses on the MM is
45、sues in the application layer or in the service stratum. In the application layer, the IP multimedia subsystem (IMS) platform will be considered and enhanced to provide seamless mobility. This Recommendation describes the framework of MM in the NGN service stratum. For this purpose, the MM functiona
46、l architecture based on the IMS platform is discussed, and the service control function (SCF) of the IMS will be investigated and further enhanced to support seamless mobility. Based on the functional architecture, the procedural information flows will be described for location management and handov
47、er control. 4 Rec. ITU-T Y.2809 (11/2011) 7 Functional architecture for MM in the service stratum 7.1 Generic architectural model The generic architectural model for MM in the service stratum is described in Figure 2, in which the MM functionality is provided via collaborative interactions between t
48、he functional entities (FEs) in the SCF and transport function (TF). Y.2809(11)_F02SAA-FESUP-FEP/S-CSC-FESL-FEService control functionS-HC-FES-HC-FES-HC-FEVisitednetworkFETransport functionCNHome networkMNMNFEFEFE FEFEFE FEFEFigure 2 Generic architecture of mobility management (MM) in the service st
49、ratum The SCF may comprise the following components, which are described in the NGN architecture ITU-T Y.2012: call session control functional entity (CSC-FE); service authentication authorization functional entity (SAA-FE); service user profile functional entity (SUP-FE); subscription locator functional entity (SL-FE). In addition, the handover control FE in the service stratum (S-HC-FE) is defined to support the handover of users in the service stratum. Such S-HC-FE
