1、 International Telecommunication Union ITU-T Y.2236TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (09/2009) SERIES Y: GLOBAL INFORMATION INFRASTRUCTURE, INTERNET PROTOCOL ASPECTS AND NEXT-GENERATION NETWORKS Next Generation Networks Service aspects: Service capabilities and service architecture Fra
2、mework for NGN support of multicast-based services Recommendation ITU-T Y.2236 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.29
3、9 Network 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 Architec
4、ture, access, 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.
5、1999 NEXT 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.2249Service aspects: Interoperability of services and networks in NGN Y.2250Y.2299 Numbering
6、, naming and addressing Y.2300Y.2399 Network management Y.2400Y.2499 Network control architectures and protocols Y.2500Y.2599 Future networks Y.2600Y.2699 Security Y.2700Y.2799 Generalized mobility Y.2800Y.2899 Carrier grade open environment Y.2900Y.2999 For further details, please refer to the list
7、 of ITU-T Recommendations. Rec. ITU-T Y.2236 (09/2009) i Recommendation ITU-T Y.2236 Framework for NGN support of multicast-based services Summary Recommendation ITU-T Y.2236 provides a framework for NGN support of multicast-based services. In particular, it provides general descriptions of NGN mult
8、icast capabilities and functional requirements for each functional group of the NGN architecture. Source Recommendation ITU-T Y.2236 was approved on 12 September 2009 by ITU-T Study Group 13 (2009-2012) under Recommendation ITU-T A.8 procedures. Keywords Multicast, multicast-based services, NGN mult
9、icast capabilities. ii Rec. ITU-T Y.2236 (09/2009) 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 Standardization Sector (ITU-T) is a pe
10、rmanent 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 meets every four years, estab
11、lishes 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 purview, the necessary sta
12、ndards 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 voluntary. However, the Re
13、commendation 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“ and the negative equivalents
14、 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 involve the use of a claimed
15、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 Recommendation, ITU had not r
16、eceived 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 at http:/www.itu.int/ITU-T
17、/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 Y.2236 (09/2009) iii CONTENTS Page 1 Scope 1 2 References. 1 3 Definitions 1 3.1 Terms defined elsewhere 1 3.2 Terms defined in this Re
18、commendation . 2 4 Abbreviations and acronyms 2 5 Conventions 3 6 Introduction 3 7 Multicast communication modes 4 7.1 One-to-many multicast communication mode . 4 7.2 Many-to-many multicast communication mode . 4 7.3 Many-to-one multicast communication mode 5 8 General description of NGN multicast
19、capabilities 5 8.1 Multicast data delivery . 5 8.2 Multicast group management . 6 8.3 Multicast service control 6 8.4 QoS control . 7 8.5 Security . 7 8.6 Mobility 8 8.7 Accounting and charging 8 9 Functional requirements for multicast-based services 8 9.1 NGN multicast framework architecture . 9 9.
20、2 Service stratum functional requirements 10 9.3 Transport stratum functional requirements 11 9.4 End-user functional requirements . 12 9.5 Management functional requirements 13 9.6 Accounting and charging functional requirements . 14 Appendix I Example scenario of multicast-based services . 15 Appe
21、ndix II End-to-end multicast data delivery across multiple NGN domains . 17 Appendix III Concepts of group and phases of a multicast communication 18 III.1 Concepts of group . 18 III.2 Phases of a multicast communication . 18 Appendix IV QoS aspects of multicast communications 21 IV.1 Levels of QoS
22、agreement . 21 IV.2 QoS metrics 21 Bibliography. 22 Rec. ITU-T Y.2236 (09/2009) 1 Recommendation ITU-T Y.2236 Framework for NGN support of multicast-based services 1 Scope This Recommendation describes a framework for NGN support of multicast-based services. It provides a general description of NGN
23、multicast capabilities and the functional requirements for each functional group of the NGN architecture (i.e., transport stratum functions, service stratum functions, end-user functions and management functions). Specific multicast-based services, as well as the actual implementation of NGN multica
24、st capabilities for different network technologies, are out of scope of this Recommendation. 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 time of publication, the e
25、ditions 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. A list of the currently v
26、alid 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 X.601 Recommendation ITU-T X.601 (2000), Multi-peer communications framework. ITU-T X.603 Recommendation ITU-T
27、X.603 (2004) | ISO/IEC 16512-1:2005, Information technology Relayed multicast protocol: Framework. ITU-T Y.2011 Recommendation ITU-T Y.2011 (2004), General principles and general reference model for next generation networks. ITU-T Y.2012 Recommendation ITU-T Y.2012 (2006), Functional requirements an
28、d architecture of the NGN release 1. ITU-T Y.2201 Recommendation ITU-T Y.2201 (2007), NGN release 1 requirements. ITU-T Y.2233 Recommendation ITU-T Y.2233 (2008), Requirements and framework allowing accounting and charging capabilities in NGN. 3 Definitions 3.1 Terms defined elsewhere This Recommend
29、ation uses the following terms defined elsewhere: 3.1.1 active group ITU-T X.601: A set of enrolled group members that has entered the multicast data transfer phase; satisfying the group-characteristics requirements. 3.1.2 multicast ITU-T X.603: A data delivery scheme where the same data unit is tra
30、nsmitted from a single source to multiple destinations in a single invocation of service. 3.1.3 multicast group ITU-T X.601: A set of service users that abide by appropriate group-membership criteria, or a set of rules belonging to a group that enables multicast-based services and applications. 2 Re
31、c. ITU-T Y.2236 (09/2009) 3.1.4 nomadism b-ITU-T Q.1706: The ability of the users to change their network access point on moving. When changing the network access point, the users service session is completely stopped and then started again, i.e., there is no service continuity or hand-over used. It
32、 is assumed that normal usage pattern is that users shut down their service session before attaching to a different access point. 3.1.5 personal mobility b-ITU-T Q.1706: This is the mobility for those scenarios where the user changes the terminal used for network access at different locations. The a
33、bility of a user to access telecommunication services at any terminal on the basis of a personal identifier, and the capability of the network to provide those services delineated in the users service profile. 3.1.6 service continuity ITU-T Y.2201: The ability for a moving object to maintain ongoing
34、 service over including current states, such as users network environment and session for a service. 3.1.7 terminal mobility b-ITU-T Q.1706: This is the mobility for those scenarios where the same terminal equipment is moving or is used at different locations. The ability of a terminal to access tel
35、ecommunication services from different locations and while in motion, and the capability of the network to identify and locate that terminal. 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 group: A set of service users using a particular service. NOTE
36、 The concept of group allows defining a set of entities as a virtual single entity. One of the main reasons to create a group is the possibility to name and address all group members with a single name, a single address, or unified characteristics of group communications, called group-name, group-ad
37、dress, or group-characteristics respectively. 3.2.2 multicast connection: A transmission path used for data transfer among members of a multicast group. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations and acronyms: ANI Applications to Network Interface DMB Digital M
38、ultimedia Broadcasting EPG Electronic Program Guide FTP File Transfer Protocol IGMP Internet Group Management Protocol IP Internet Protocol IPTV Internet Protocol Television MPLS MultiProtocol Label Switching NGN Next Generation Network NNI Network to Network Interface PON Passive Optical Network Qo
39、S Quality of Service SDR Session Directory TTL Time to Live VoD Video on Demand Rec. ITU-T Y.2236 (09/2009) 3 5 Conventions In this Recommendation: The keywords “is required to“ indicate a requirement which must be strictly followed and from which no deviation is permitted, if conformance to this Re
40、commendation is to be claimed. The keywords “is prohibited from“ indicate a requirement which must be strictly followed and from which no deviation is permitted, if conformance to this Recommendation is to be claimed. The keywords “is recommended“ indicate a requirement which is recommended but whic
41、h is not absolutely required. Thus, this requirement need not be present to claim conformance. The keywords “is not recommended“ indicate a requirement which is not recommended but which is not specifically prohibited. Thus, conformance with this Recommendation can still be claimed even if this requ
42、irement is present. The keywords “can optionally“ indicate an optional requirement which is permissible, without implying any sense of being recommended. This term is not intended to imply that the vendors implementation must provide the option and the feature can be optionally enabled by the networ
43、k operator/service provider. Rather, it means the vendor may optionally provide the feature and still claim conformance with this Recommendation. 6 Introduction As shown in Figure 6-1 below, various services multimedia conference, linear TV, file distribution and entertainment applications such as g
44、ames being representative examples may require that NGN supports multicast capabilities. NGNNGN multicast capabilitiesServices using NGN multicast capabilitiesLinearTVMultimediaConferenceFileDistributionGamesFigure 6-1 Examples of services using NGN multicast capabilities NGN may provide multicast c
45、apabilities based on different network technologies (e.g., IP, MPLS, Ethernet and PON); these different network technologies do not necessarily provide identical multicast related functionalities. This Recommendation provides the description of requirements for NGN multicast capabilities. Detailed r
46、equirements for specific network technologies are out of scope of this Recommendation. Appendix I describes an example scenario of multicast-based services. 4 Rec. ITU-T Y.2236 (09/2009) 7 Multicast communication modes This clause describes multicast communication modes. Three types of multicast com
47、munication modes are required to be supported by NGN multicast capabilities ITU-T Y.2201. NOTE The actual mechanisms to provide each multicast communication mode may vary according to the network environment, and their usage may be implementation dependent. 7.1 One-to-many multicast communication mo
48、de This mode can be applied to deliver data to multiple recipients. It assumes one sender and a receiving group consisting of multiple recipients. SenderReceiverUnidirectional data pathFigure 7-1 One-to-many multicast communication mode Examples of services that may use the one-to-many multicast com
49、munication mode include: Real-time services such as linear TV and digital multimedia broadcasting (DMB); Reliable services such as file distribution, software update and e-learning. 7.2 Many-to-many multicast communication mode This mode can be applied to deliver data from multiple senders to multiple recipients. It assumes a group consisting of multiple senders and multiple recipients. Figure 7-2 Many-to-many multicast communication mode For the many-to-many multicast communicatio
