ETSI TS 126 346 V8.6.0 (2012-01) Technical Specification Universal Mobile Telecommunications System (UMTS); LTE; Multimedia Broadcast/Multicast Service (MBMS); Protocols and codecs (3GPP TS 26.346 version 8.6.0 Release 8) 3GPP TS 26.346 version 8.6.0 Release 8 1 ETSI TS 126 346 V8.6.0 (2012-01) Reference RTS/TSGS-0426346v860 Keywords LTE,UMTS ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice Individual copies of the present document can be downloaded from: http://www.etsi.org The present document may be made available in more than one electronic version or in print. In any case of existing or perceived difference in contents between such versions, the reference version is the Portable Document Format (PDF). 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DECTTM, PLUGTESTSTM, UMTSTM and the ETSI logo are Trade Marks of ETSI registered for the benefit of its Members. 3GPPTM and LTE™ are Trade Marks of ETSI registered for the benefit of its Members and of the 3GPP Organizational Partners. GSM® and the GSM logo are Trade Marks registered and owned by the GSM Association. ETSI 3GPP TS 26.346 version 8.6.0 Release 8 2 ETSI TS 126 346 V8.6.0 (2012-01) Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web server (http://ipr.etsi.org). Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web server) which are, or may be, or may become, essential to the present document. Foreword This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP). The present document may refer to technical specifications or reports using their 3GPP identities, UMTS identities or GSM identities. These should be interpreted as being references to the corresponding ETSI deliverables. The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under http://webapp.etsi.org/key/queryform.asp. ETSI 3GPP TS 26.346 version 8.6.0 Release 8 3 ETSI TS 126 346 V8.6.0 (2012-01) Contents Intellectual Property Rights ................................................................................................................................ 2 Foreword ............................................................................................................................................................. 2 Foreword ............................................................................................................................................................. 9 Introduction ........................................................................................................................................................ 9 1 Scope ...................................................................................................................................................... 10 2 References .............................................................................................................................................. 10 3 Definitions and abbreviations ................................................................................................................. 14 3.1 Definitions ........................................................................................................................................................ 14 3.2 Abbreviations ................................................................................................................................................... 15 4 MBMS system description ..................................................................................................................... 16 4.1 MBMS functional layers .................................................................................................................................. 16 4.2 MBMS User Service Entities ........................................................................................................................... 16 4.3 MBMS bearer service architecture ................................................................................................................... 17 4.4 Functional Entities to support MBMS User Services ....................................................................................... 17 4.4.1 MBMS User Service Architecture .............................................................................................................. 17 4.4.1a Content Provider / Multicast Broadcast Source .......................................................................................... 19 4.4.2 MBMS Key Management Function ............................................................................................................ 19 4.4.3 MBMS Session and Transmission Function ............................................................................................... 19 4.4.4 User Service Discovery / Announcement function ..................................................................................... 19 4.4.5 Interactive Announcement Function ........................................................................................................... 20 4.4.6 MBMS UE .................................................................................................................................................. 20 4.5 Usage of identity of MBMS session ................................................................................................................. 20 4.6 Time Synchronization between the BM-SC and MBMS UEs ......................................................................... 21 5 Procedures and protocols........................................................................................................................ 21 5.1 Introduction ...................................................................................................................................................... 21 5.2 User Service Discovery/Announcement ........................................................................................................... 21 5.2.1 Introduction................................................................................................................................................. 21 5.2.2 MBMS User Service Description Metadata Fragments .............................................................................. 22 5.2.2.1 Introduction ........................................................................................................................................... 22 5.2.2.2 Session Description ............................................................................................................................... 23 5.2.2.3 Associated Delivery Procedure Description .......................................................................................... 24 5.2.2.4 Service Protection Description .............................................................................................................. 24 5.2.2.5 FEC Repair Stream Description ............................................................................................................ 24 5.2.3 User Service Announcement over a MBMS bearer .................................................................................... 24 5.2.3.1 General .................................................................................................................................................. 24 5.2.3.2 Metadata Envelope Transport ............................................................................................................... 24 5.2.3.3 Metadata Envelope and Metadata Fragment Association with FLUTE ................................................ 24 5.2.4 User Service Announcement using Interactive Announcement Function ................................................... 25 5.2.5 User Service Announcement over point-to-point push bearers................................................................... 25 5.2.5.1 General .................................................................................................................................................. 25 5.2.5.2 Supported Metadata Syntaxes ............................................................................................................... 25 5.2.5.3 Consistency Control and Syntax Independence .................................................................................... 25 5.2.5.4 Metadata Envelope Definition .............................................................................................................. 25 5.2.5.5 Delivery of the Metadata Envelope ....................................................................................................... 25 5.2.5.6 Metadata Envelope Transport ............................................................................................................... 26 5.2.5.7 User service announcement over SMS bearers ..................................................................................... 26 5.2.5.8 User service announcement over HTTP push bearers ........................................................................... 26 5.2.6 Metadata Fragment Encapsulation to aggregate Service Announcement Documents ................................ 26 5.2.7 Registration and Deregistration Procedure for MBMS User Service Consumption ................................... 26 5.3 User Service Initiation/Termination ................................................................................................................. 27 5.3.1 Initiation of MBMS Bearer Service based Services ................................................................................... 27 5.3.2 Termination of MBMS Bearer Service based Services .............................................................................. 28 ETSI 3GPP TS 26.346 version 8.6.0 Release 8 4 ETSI TS 126 346 V8.6.0 (2012-01) 5.3.3 Initiation of Unicast Bearer Service based Services ................................................................................... 29 5.3.4 Termination of Unicast Bearer Service based Services .............................................................................. 29 5.3.5 Scalable Service Initiation and Termination for MBMS Services .............................................................. 30 5.3.5.1 General .................................................................................................................................................. 30 5.3.5.2 Randomization of Service Initiation over Time .................................................................................... 30 5.3.5.3 Randomization of Service Termination over Time ............................................................................... 30 5.4 MBMS Data Transfer Procedure ...................................................................................................................... 31 5.4.1 MBMS Data Transfer Procedure using MBMS Bearer Services ................................................................ 31 5.4.2 MBMS Data Transfer Procedure using other UMTS Bearer Services ....................................................... 32 5.5 MBMS Protocols .............................................................................................................................................. 32 6 Introduction on Delivery Methods ......................................................................................................... 32 7 Download Delivery Method ................................................................................................................... 32 7.1 Introduction ...................................................................................................................................................... 32 7.2 FLUTE usage for MBMS download ................................................................................................................ 33 7.2.1 Fragmentation of Files ................................................................................................................................ 34 7.2.2 Symbol Encoding Algorithm ...................................................................................................................... 34 7.2.3 Blocking Algorithm .................................................................................................................................... 34 7.2.4 Congestion Control ..................................................................................................................................... 34 7.2.5 Content Encoding of Files for Transport .................................................................................................... 34 7.2.6 Transport File Grouping ............................................................................................................................. 34 7.2.7 Signalling of Parameters with Basic ALC/FLUTE Headers ....................................................................... 35 7.2.8 Signalling of Parameters with FLUTE Extension Headers ......................................................................... 35 7.2.9 Signalling of Parameters with FDT Instances ............................................................................................. 35 7.2.10 FDT Schema ............................................................................................................................................... 37 7.2.10.1 Extended FLUTE FDT Schema ............................................................................................................ 37 7.2.10.2 3GPP FDT Extension Type Schema ..................................................................................................... 37 7.2.10.3 IETF FDT Schema ................................................................................................................................ 38 7.2.10.4 Example of FDT .................................................................................................................................... 38 7.2.10.5 3GPP FDT Extensions .......................................................................................................................... 39 7.2.11 MBMS Session Identify .............................................................................................................................. 39 7.2.12 FEC Scheme definition ............................................................................................................................... 39 7.2.12.1 General .................................................................................................................................................. 39 7.2.13 Caching Directives ...................................................................................................................................... 39 7.2.14 Indicating a full FDT snapshot ................................................................................................................... 40 7.3 SDP for Download Delivery Method ............................................................................................................... 41 7.3.1 Introduction................................................................................................................................................. 41 7.3.2 SDP Parameters for MBMS download session ........................................................................................... 41 7.3.2.1 Sender IP address .................................................................................................................................. 41 7.3.2.2 Number of channels .............................................................................................................................. 41 7.3.2.3 Destination IP address and port number for channels ........................................................................... 42 7.3.2.4 Transport Session Identifier (TSI) of the session .................................................................................. 42 7.3.2.5 Multiple objects transport indication ..................................................................................................... 42 7.3.2.6 Session Timing Parameters ................................................................................................................... 42 7.3.2.7 Mode of MBMS bearer per media ........................................................................................................ 42 7.3.2.8 FEC capabilities and related parameters ............................................................................................... 43 7.3.2.9 Service-language(s) per media .............................................................................................................. 43 7.3.2.10 Bandwidth Specification ....................................................................................................................... 44 7.3.3 SDP Examples for FLUTE Session ............................................................................................................ 44 7.4 OMA Push usage for MBMS Download .......................................................................................................... 44 7.4.1 Introduction................................................................................................................................................. 44 7.4.2 HTTP registration and deregistration procedure ......................................................................................... 44 7.4.3 MBMS Download Delivery Method over OMA push bearers ................................................................... 45 7.5 FLUTE session setup and control with RTSP .................................................................................................. 46 7.5.1 Introduction................................................................................................................................................. 46 7.5.2 SDP handling .............................................................................................................................................. 46 7.5.3 RTSP SETUP Method ................................................................................................................................ 46 7.5.4 RTSP PLAY Method .................................................................................................................................. 46 7.5.5 RTSP PAUSE Method ................................................................................................................................ 46 7.5.6 RTSP TEARDOWN Method ...................................................................................................................... 46 8 Streaming delivery method .................................................................................................................... 47 ETSI 3GPP TS 26.346 version 8.6.0 Release 8 5 ETSI TS 126 346 V8.6.0 (2012-01) 8.1 Introduction ...................................................................................................................................................... 47 8.2 Transport protocol ............................................................................................................................................ 47 8.2.1 RTP payload formats for media .................................................................................................................. 47 8.2.2 FEC mechanism for RTP ............................................................................................................................ 47 8.2.2.1 Sending Terminal Operation (Informative) ........................................................................................... 49 8.2.2.2 Receiving Terminal Operation (Informative) ........................................................................................ 50 8.2.2.3 (Void) .................................................................................................................................................... 50 8.2.2.4 Packet format for FEC source packets .................................................................................................. 51 8.2.2.5 Packet Format for Repair packets ......................................................................................................... 51 8.2.2.6 Structure of the FEC source block ........................................................................................................ 52 8.2.2.7 FEC block Construction algorithm and example (informative) ............................................................ 52 8.2.2.8 MBMS FEC scheme definition ............................................................................................................. 53 8.2.2.9 Source FEC Payload ID ........................................................................................................................ 53 8.2.2.10 Repair FEC payload ID ......................................................................................................................... 54 8.2.2.10a FEC Object Transmission information.................................................................................................. 54 8.2.2.11 Hypothetical FEC Decoder ................................................................................................................... 54 8.2.2.12 FEC encoding procedures ..................................................................................................................... 55 8.2.2.13 Signalling .............................................................................................................................................. 55 8.2.2.13a SDP for FEC source packet streams ..................................................................................................... 56 8.2.2.14 SDP for FEC repair packet streams ....................................................................................................... 56 8.2.2.15 Signalling example for FEC .................................................................................................................. 56 8.2.3 General RTP Header Extension Mechanism............................................................................................... 59 8.2.3.1 Introduction ........................................................................................................................................... 59 8.2.3.2 Timestamp Offset .................................................................................................................................. 59 8.3 Session description ........................................................................................................................................... 59 8.3.1 SDP Parameters for MBMS streaming session ........................................................................................... 59 8.3.1.1 Sender IP address .................................................................................................................................. 60 8.3.1.2 Destination IP address and port number for channels ........................................................................... 60 8.3.1.3 Media Description ................................................................................................................................. 60 8.3.1.4 Session Timing Parameters ................................................................................................................... 60 8.3.1.5 Mode of MBMS bearer per media ........................................................................................................ 61 8.3.1.6 Service-language(s) per media .............................................................................................................. 61 8.3.1.7 Bandwidth specification ........................................................................................................................ 61 8.3.1.8 FEC Parameters ..................................................................................................................................... 61 8.3.1.9 FEC Flow ID attribute ........................................................................................................................... 62 8.3.1.10 Buffer Requirement Signaling .............................................................................................................. 62 8.3.1.11 Interleaving Signaling ........................................................................................................................... 63 8.3.2 SDP Example for Streaming Session .......................................................................................................... 63 8.3.2.1 SDP Description for QoE Metrics ......................................................................................................... 63 8.4 Quality of Experience ....................................................................................................................................... 64 8.4.1 General ........................................................................................................................................................ 64 8.4.2 QoE Metrics ................................................................................................................................................ 64 8.4.2.1 Corruption duration metric .................................................................................................................... 65 8.4.2.2 Rebuffering duration metric .................................................................................................................. 65 8.4.2.3 Initial buffering duration metric ............................................................................................................ 65 8.4.2.4 Successive loss of RTP packets ............................................................................................................ 66 8.4.2.5 Frame rate deviation .............................................................................................................................. 66 8.4.2.6 Jitter duration ........................................................................................................................................ 66 8.4.2.7 Content Access/Switch Time ................................................................................................................ 66 8.4.3 Example metrics initiation with SDP .......................................................................................................... 67 8.5 Using MBMS Streaming delivery on Unicast .................................................................................................. 67 9 Associated delivery procedures .............................................................................................................. 68 9.1 Introduction ...................................................................................................................................................... 68 9.2 Associated Procedure Description .................................................................................................................... 68 9.3 File Repair Procedure ....................................................................................................................................... 69 9.3.1 Introduction................................................................................................................................................. 69 9.3.2 Starting Time of the Associated Delivery Procedure for MBMS Download Delivery ............................... 70 9.3.3 Identification of Missing Data from an MBMS Download ........................................................................ 70 9.3.4 Back-off Timing the Procedure Initiation Messaging for Scalability ......................................................... 71 9.3.4.1 Offset time............................................................................................................................................. 71 9.3.4.2 Random Time Period ............................................................................................................................ 71 ETSI 3GPP TS 26.346 version 8.6.0 Release 8 6 ETSI TS 126 346 V8.6.0 (2012-01) 9.3.4.3 Back-off Time ....................................................................................................................................... 71 9.3.4.4 Reset of the Back-off Timer .................................................................................................................. 71 9.3.5 File Repair Server Selection ....................................................................................................................... 72 9.3.5.1 List of Server URIs ............................................................................................................................... 72 9.3.5.2 Selection from the Server URI List ....................................................................................................... 72 9.3.6 File Repair Request Message ...................................................................................................................... 72 9.3.6.1 File Repair Request Message Format .................................................................................................... 72 9.3.7 File Repair Response Message ................................................................................................................... 74 9.3.7.1 File Repair Response Messages Codes ................................................................................................. 75 9.3.7.2 File Repair Response Message Format for HTTP Carriage of Repair Data .......................................... 76 9.3.7.3 File Repair Response for Broadcast/Multicast of Repair Data .............................................................. 77 9.3.7.4 File Repair Response Message Format for HTTP carriage of Complete Files ..................................... 78 9.3.8 Server Not Responding Error Case ............................................................................................................. 78 9.4 The Reception Reporting Procedure................................................................................................................. 78 9.4.1 Identifying Complete File Reception from MBMS Download ................................................................... 79 9.4.2 Identifying Complete MBMS Delivery Session Reception ........................................................................ 79 9.4.3 Determining Whether a Reception Report Is Required .............................................................................. 79 9.4.4 Request Time Selection .............................................................................................................................. 80 9.4.5 Reception Report Server Selection ............................................................................................................. 80 9.4.6 Reception Report Message ......................................................................................................................... 80 9.4.7 Reception Report Response Message ......................................................................................................... 81 9.5 XML-Schema for Associated Delivery Procedures ......................................................................................... 82 9.5.1 Generic Associated Delivery Procedure Description .................................................................................. 82 9.5.2 Example Associated Delivery Procedure Description Instance .................................................................. 82 9.5.3 XML Syntax for a Reception Report Request ............................................................................................ 83 9.5.3.1 Use of Specific Values .......................................................................................................................... 84 9.5.3.2 Example XML for the Reception Report Request ................................................................................ 84 10 Media codecs and formats ...................................................................................................................... 85 10.1 General ............................................................................................................................................................. 85 10.2 Speech .............................................................................................................................................................. 85 10.3 Audio ................................................................................................................................................................ 85 10.4 Synthetic audio ................................................................................................................................................. 85 10.5 Video ................................................................................................................................................................ 86 10.6 Still images ....................................................................................................................................................... 86 10.7 Bitmap graphics ................................................................................................................................................ 86 10.8 Vector graphics ................................................................................................................................................ 87 10.9 Text .................................................................................................................................................................. 87 10.10 Timed text ........................................................................................................................................................ 87 10.11 3GPP file format ............................................................................................................................................... 87 10.12 Scene Description ............................................................................................................................................. 87 11 MBMS Metadata .................................................................................................................................... 88 11.1 The MBMS Metadata Envelope ....................................................................................................................... 88 11.1.1 Supported Metadata Syntaxes ..................................................................................................................... 88 11.1.2 Consistency Control and Syntax Independence .......................................................................................... 88 11.1.3 Metadata Envelope Definition .................................................................................................................... 88 11.1.4 Delivery of the Metadata Envelope ............................................................................................................ 89 11.2 MBMS User Service Description Metadata Fragment ..................................................................................... 90 11.2.1 Definition of the MBMS User Service Bundle Description ....................................................................... 90 11.2.1.1 Initial Definition .................................................................................................................................................. 90 11.2.1.2 Extensions to the User Service Bundle Description .............................................................................. 91 11.2.2 Example MBMS User Service Description Instances ................................................................................ 93 11.3 Service Protection Description Metadata Fragment ......................................................................................... 95 11.3.1 Definition of the Protection Description ..................................................................................................... 95 11.3.2 Example of a Security Description: ............................................................................................................ 97 11.4 Service Protection Registration Format ............................................................................................................ 97 11.4.1 Data Format ................................................................................................................................................ 97 11.4.2 Example ...................................................................................................................................................... 98 11.5 Service Protection De-Registration Format ...................................................................................................... 98 11.5.1 Data Format ................................................................................................................................................ 98 11.5.2 Example ...................................................................................................................................................... 98 ETSI 3GPP TS 26.346 version 8.6.0 Release 8 7 ETSI TS 126 346 V8.6.0 (2012-01) 11.6 Service Protection MSK Request Format ......................................................................................................... 98 11.6.1 Data Format ................................................................................................................................................ 98 11.6.2 Example ...................................................................................................................................................... 99 11.7 Service Protection Registration and De-Registration Response Format .......................................................... 99 11.7.1 Data Format ................................................................................................................................................ 99 11.7.2 Example .................................................................................................................................................... 100 11.8 Service Protection MSK Response Format .................................................................................................... 100 11.8.1 Data Format .............................................................................................................................................. 100 11.8.2 Example .................................................................................................................................................... 100 11.9 MBMS Feature Requirements .................................................................................................................. 101 Annex A (normative): FLUTE Support Requirements .................................................................. 102 Annex B (normative): FEC encoder specification ........................................................................... 104 B.1 Definitions, Symbols and Abbreviations .............................................................................................. 104 B.1.1 Definitions ...................................................................................................................................................... 104 B.1.2 Symbols .......................................................................................................................................................... 105 B.1.3 Abbreviations ................................................................................................................................................. 106 B.2 Overview .............................................................................................................................................. 106 B.3 File download ....................................................................................................................................... 107 B.3.1 Void ................................................................................................................................................................ 107 B.3.2 Void ................................................................................................................................................................ 107 B.3.3 Void ................................................................................................................................................................ 107 B.3.4 Example parameters ....................................................................................................................................... 107 B.3.4.1 Parameter derivation algorithm................................................................................................................. 107 B.3.4.2 Examples .................................................................................................................................................. 107 B.4 Streaming ............................................................................................................................................. 108 B.4.1 Source block construction .............................................................................................................................. 108 B.4.2 Encoding packet construction......................................................................................................................... 108 B.4.3 Transport ........................................................................................................................................................ 108 B.4.4 Example parameters ....................................................................................................................................... 109 B.4.4.1 Parameter derivation algorithm................................................................................................................. 109 B.4.4.2 Examples .................................................................................................................................................. 110 B.5 Systematic Raptor encoder ................................................................................................................... 110 B.5.1 Encoding overview ......................................................................................................................................... 110 B.5.2 First encoding step: Intermediate symbol Generation .................................................................................... 110 B.5.2.1 General ...................................................................................................................................................... 110 B.5.2.2 Source symbol triples................................................................................................................................ 111 B.5.2.3 Pre-coding relationships ........................................................................................................................... 111 B.5.2.4 Intermediate symbols ................................................................................................................................ 112 B.5.2.4.1 Definition ............................................................................................................................................ 112 B.5.2.4.2 Example method for calculation of intermediate symbols .................................................................. 112 B.5.3 Second encoding step: LT encoding ............................................................................................................... 113 B.5.4 Generators ...................................................................................................................................................... 114 B.5.4.1 Random Generator .................................................................................................................................... 114 B.5.4.2 Degree Generator ...................................................................................................................................... 114 B.5.4.3 LT Encoding Symbol Generator ............................................................................................................... 114 B.5.4.4 Triple generator ........................................................................................................................................ 115 B.6 Systematic Indices J(K)) ....................................................................................................................... 115 B.7 Random Numbers ................................................................................................................................. 115 B.8 Void ...................................................................................................................................................... 115 Annex C (informative): IANA registration ........................................................................................ 116 C.1 Registration of SDP Protocol Identifiers for Source packet ................................................................. 116 C.2 Registration of SDP Protocol identifier for repair packets ................................................................... 116 ETSI 3GPP TS 26.346 version 8.6.0 Release 8 8 ETSI TS 126 346 V8.6.0 (2012-01) C.3 Registration of MIME type "application/simpleSymbolContainer" .................................................... 116 C.4 Registration of MIME type "application/mbms-user-service-description+xml " ................................ 117 C.5 Registration of MIME type "application/mbms-envelope+xml " ........................................................ 118 C.6 Registration of MIME type "application/mbms-protection-description+xml ".................................... 120 C.7 Registration of MIME type "application/mbms-associated-procedure-description+xml" ................... 121 C.8 Registration of MIME type "application/mbms-msk+xml" ................................................................. 122 C.9 Registration of MIME type "application/mbms-register+xml" ............................................................ 123 C.10 Registration of MIME type "application/mbms-deregister+xml" ........................................................ 124 C.11 Registration of MIME type "application/mbms-reception-report+xml" .............................................. 125 C.12 Registration of MIME type "application/mbms-msk-response+xml" .................................................. 126 C.13 Registration of MIME type "application/mbms-register-response+xml" ............................................ 127 Annex D (informative): RTP packetization guidelines ..................................................................... 129 Annex E (informative): Void ............................................................................................................... 130 Annex F (informative): Hybrid Streaming Delivery ......................................................................... 131 F.1 Introduction .............................................................................................................................................. 131 F.2 Switching between MBMS and PSS Access ............................................................................................ 131 F.2.1 Synchronization of Flows ...................................................................................................................................... 131 F.2.2 Switching from MBMS to PSS Access .................................................................................................................. 131 F.2.3 Switching from PSS to MBMS Access .................................................................................................................. 132 Annex G (informative): Guidelines for Channel Tune-in and Switch Time Reduction ................. 133 G.1 Interleaving for Tune-in Time Reduction of FEC protected MBMS Services ........................................ 133 G.1.1 Timestamp Offsets ......................................................................................................................................... 133 G.1.2 Early Playout .................................................................................................................................................. 134 G.2 FEC Stream & Channel Bundling ........................................................................................................ 134 G.2.1 Introduction ........................................................................................................................................................... 134 G.2.1.1 Full Channel Bundling (All flows of several user services) ............................................................................... 134 G.2.1.2 No Bundling ....................................................................................................................................................... 135 G.2.1.3 Partial Channel Bundling (Some flows of several user services) ....................................................................... 135 G.2.1.3 Stream Bundling (All flows of a single user services) ....................................................................................... 135 Annex H (informative): Change history ............................................................................................. 136 History ............................................................................................................................................................ 138 ETSI 3GPP TS 26.346 version 8.6.0 Release 8 9 ETSI TS 126 346 V8.6.0 (2012-01) Foreword This Technical Specification has been produced by the 3rd Generation Partnership Project (3GPP). The contents of the present document are subject to continuing work within the TSG and may change following formal TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an identifying change of release date and an increase in version number as follows: Version x.y.z where: x the first digit: 1 presented to TSG for information; 2 presented to TSG for approval; 3 or greater indicates TSG approved document under change control. y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections, updates, etc. z the third digit is incremented when editorial only changes have been incorporated in the document. Introduction MBMS is a point-to-multipoint service in which data is transmitted from a single source entity to multiple recipients. Transmitting the same data to multiple recipients allows network resources to be shared. The MBMS bearer service offers two modes: • Broadcast Mode. • Multicast Mode. MBMS user services can be built on top of the MBMS bearer service. Further, the MBMS User Services may use other UMTS bearer services to deliver data. The present document specifies two delivery methods for the MBMS user services: download and streaming. Examples of applications using the download delivery method are news and software upgrades. Delivery of live music is an example of an application using the streaming delivery method. There can be several MBMS user services. The objective of the present document is the definition of a set of media codecs, formats and transport/application protocols to enable the deployment of MBMS user services. The present document takes into consideration the need to maximize the reuse of components of already specified services like PSS and MMS. ETSI