ETSI TS 126 346 V6.3.0 (2005-12) Technical Specification Universal Mobile Telecommunications System (UMTS); Multimedia Broadcast/Multicast Service (MBMS); Protocols and codecs (3GPP TS 26.346 version 6.3.0 Release 6) 3GPP TS 26.346 version 6.3.0 Release 6 1 ETSI TS 126 346 V6.3.0 (2005-12) Reference RTS/TSGS-0426346v630 Keywords 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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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 6.3.0 Release 6 3 ETSI TS 126 346 V6.3.0 (2005-12) Contents Intellectual Property Rights................................................................................................................................2 Foreword.............................................................................................................................................................2 Foreword.............................................................................................................................................................8 Introduction........................................................................................................................................................8 1 Scope........................................................................................................................................................9 2 References................................................................................................................................................9 3 Definitions and abbreviations.................................................................................................................12 3.1 Definitions........................................................................................................................................................12 3.2 Abbreviations...................................................................................................................................................13 4 MBMS system description.....................................................................................................................14 4.1 MBMS functional layers..................................................................................................................................14 4.2 MBMS User Service Entities...........................................................................................................................15 4.3 MBMS bearer service architecture...................................................................................................................16 4.4 Functional Entities to support MBMS User Services.......................................................................................16 4.4.1 MBMS User Service Architecture..............................................................................................................16 4.4.1a Content Provider / Multicast Broadcast Source..........................................................................................18 4.4.2 MBMS Key Management Function............................................................................................................18 4.4.3 MBMS Session and Transmission Function...............................................................................................18 4.4.4 User Service Discovery / Announcement function.....................................................................................18 4.4.5 Interactive Announcement Function...........................................................................................................18 4.4.6 MBMS UE..................................................................................................................................................19 4.5 Usage of identity of MBMS session.................................................................................................................19 4.6 Time Synchronization between the BM-SC and MBMS UEs.........................................................................20 5 Procedures and protocol.........................................................................................................................20 5.1 Introduction......................................................................................................................................................20 5.2 User Service Discovery/Announcement...........................................................................................................20 5.2.1 Introduction.................................................................................................................................................20 5.2.2 MBMS User Service Description Metadata Fragments..............................................................................20 5.2.2.1 Introduction...........................................................................................................................................20 5.2.2.2 Session Description...............................................................................................................................22 5.2.2.3 Associated Delivery Procedure Description..........................................................................................22 5.2.2.4 Service Protection Description..............................................................................................................22 5.2.2.5 FEC Repair Stream Description............................................................................................................22 5.2.3 User Service Announcement over a MBMS bearer....................................................................................23 5.2.3.1 General..................................................................................................................................................23 5.2.3.2 Metadata Envelope Transport...............................................................................................................23 5.2.3.3 Metadata Envelope and Metadata Fragment Association with FLUTE................................................23 5.2.4 User Service Announcement using Interactive Announcement Function...................................................23 5.2.4.1 User Service Announcement over point-to-point push bearers.............................................................23 5.2.4.1.1 Supported Metadata Syntaxes.........................................................................................................24 5.2.4.1.2 Consistency Control and Syntax Independence...............................................................................24 5.2.4.1.3 Metadata Envelope Definition.........................................................................................................24 5.2.4.1.4 Delivery of the Metadata Envelope.................................................................................................24 5.2.4.1.5 Metadata Envelope Transport..........................................................................................................24 5.2.4.1.6 User service announcement over SMS bearers................................................................................24 5.2.4.1.7 User service announcement over HTTP push bearers.....................................................................24 5.2.5 Metadata Fragment Encapsulation to aggregate Service Announcement Documents................................24 5.3 User Service Initiation/Termination.................................................................................................................25 5.3.1 Initiation......................................................................................................................................................25 5.3.2 MBMS User Service termination procedure...............................................................................................26 5.4 MBMS Data Transfer Procedure......................................................................................................................26 5.5 MBMS Protocols..............................................................................................................................................27 ETSI 3GPP TS 26.346 version 6.3.0 Release 6 4 ETSI TS 126 346 V6.3.0 (2005-12) 6 Introduction on Delivery Methods.........................................................................................................28 7 Download Delivery Method...................................................................................................................28 7.1 Introduction......................................................................................................................................................28 7.2 FLUTE usage for MBMS download................................................................................................................29 7.2.1 Fragmentation of Files................................................................................................................................30 7.2.2 Symbol Encoding Algorithm......................................................................................................................30 7.2.3 Blocking Algorithm....................................................................................................................................30 7.2.4 Congestion Control.....................................................................................................................................30 7.2.5 Content Encoding of Files for Transport....................................................................................................30 7.2.6 Transport File Grouping.............................................................................................................................30 7.2.7 Signalling of Parameters with Basic ALC/FLUTE Headers.......................................................................30 7.2.8 Signalling of Parameters with FLUTE Extension Headers.........................................................................31 7.2.9 Signalling of Parameters with FDT Instances.............................................................................................31 7.2.10 FDT Schema...............................................................................................................................................33 7.2.10.1 Extended FLUTE FDT Schema............................................................................................................33 7.2.10.2 3GPP FDT Extension Type Schema.....................................................................................................33 7.2.10.3 IETF FDT Schema................................................................................................................................34 7.2.10.4 Example of FDT....................................................................................................................................34 7.2.11 MBMS Session Identify..............................................................................................................................35 7.2.12 FEC Scheme definition...............................................................................................................................35 7.2.12.1 General..................................................................................................................................................35 7.2.12.2 FEC payload ID....................................................................................................................................35 7.2.12.3 FEC Object Transmission Information.................................................................................................35 7.3 SDP for Download Delivery Method...............................................................................................................36 7.3.1 Introduction.................................................................................................................................................36 7.3.2 SDP Parameters for MBMS download session...........................................................................................36 7.3.2.1 Sender IP address..................................................................................................................................36 7.3.2.2 Number of channels..............................................................................................................................37 7.3.2.3 Destination IP address and port number for channels...........................................................................37 7.3.2.4 Transport Session Identifier (TSI) of the session..................................................................................37 7.3.2.5 Multiple objects transport indication.....................................................................................................37 7.3.2.6 Session Timing Parameters...................................................................................................................38 7.3.2.7 Mode of MBMS bearer per media........................................................................................................38 7.3.2.8 FEC capabilities and related parameters...............................................................................................38 7.3.2.9 Service-language(s) per media..............................................................................................................39 7.3.2.10 Bandwidth Specification.......................................................................................................................39 7.3.3 SDP Examples for FLUTE Session............................................................................................................39 8 Streaming delivery method....................................................................................................................39 8.1 Introduction......................................................................................................................................................39 8.2 Transport protocol............................................................................................................................................39 8.2.1 RTP payload formats for media..................................................................................................................39 8.2.2 FEC mechanism for RTP............................................................................................................................40 8.2.2.1 Sending Terminal Operation (Informative)...........................................................................................41 8.2.2.2 Receiving Terminal Operation (Informative)........................................................................................42 8.2.2.3 (Void)....................................................................................................................................................43 8.2.2.4 Packet format for FEC source packets..................................................................................................43 8.2.2.5 Packet Format for Repair packets.........................................................................................................43 8.2.2.6 Structure of the FEC source block........................................................................................................44 8.2.2.7 FEC block Construction algorithm and example (informative)............................................................44 8.2.2.8 MBMS FEC scheme definition.............................................................................................................45 8.2.2.9 Source FEC Payload ID........................................................................................................................45 8.2.2.10 Repair FEC payload ID.........................................................................................................................46 8.2.2.10a FEC Object Transmission information..................................................................................................46 8.2.2.11 Hypothetical FEC Decoder...................................................................................................................46 8.2.2.12 FEC encoding procedures.....................................................................................................................47 8.2.2.13 Signalling..............................................................................................................................................47 8.2.2.13a SDP for FEC source packet streams.....................................................................................................48 8.2.2.14 SDP for FEC repair packet streams.......................................................................................................48 8.2.2.15 Signalling example for FEC..................................................................................................................48 8.3 Session description...........................................................................................................................................50 ETSI 3GPP TS 26.346 version 6.3.0 Release 6 5 ETSI TS 126 346 V6.3.0 (2005-12) 8.3.1 SDP Parameters for MBMS streaming session...........................................................................................50 8.3.1.1 Sender IP address..................................................................................................................................50 8.3.1.2 Destination IP address and port number for channels...........................................................................50 8.3.1.3 Media Description.................................................................................................................................51 8.3.1.4 Session Timing Parameters...................................................................................................................51 8.3.1.5 Mode of MBMS bearer per media........................................................................................................51 8.3.1.6 Service-language(s) per media..............................................................................................................51 8.3.1.7 Bandwidth specification........................................................................................................................51 8.3.1.8 FEC Parameters.....................................................................................................................................51 8.3.1.9 FEC Flow ID attribute...........................................................................................................................52 8.3.2 SDP Example for Streaming Session..........................................................................................................52 8.3.2.1 SDP Description for QoE Metrics.........................................................................................................53 8.4 Quality of Experience.......................................................................................................................................53 8.4.1 General........................................................................................................................................................53 8.4.2 QoE Metrics................................................................................................................................................54 8.4.2.1 Corruption duration metric....................................................................................................................54 8.4.2.2 Rebuffering duration metric..................................................................................................................54 8.4.2.3 Initial buffering duration metric............................................................................................................55 8.4.2.4 Successive loss of RTP packets............................................................................................................55 8.4.2.5 Frame rate deviation..............................................................................................................................55 8.4.2.6 Jitter duration........................................................................................................................................55 8.4.3 Example metrics initiation with SDP..........................................................................................................56 9 Associated delivery procedures..............................................................................................................56 9.1 Introduction......................................................................................................................................................56 9.2 Associated Procedure Description....................................................................................................................57 9.3 File Repair Procedure.......................................................................................................................................57 9.3.1 Introduction.................................................................................................................................................57 9.3.2 Starting Time of the Associated Delivery Procedure for MBMS Download Delivery...............................58 9.3.3 Identification of Missing Data from an MBMS Download........................................................................59 9.3.4 Back-off Timing the Procedure Initiation Messaging for Scalability.........................................................59 9.3.4.1 Offset time.............................................................................................................................................59 9.3.4.2 Random Time Period............................................................................................................................60 9.3.4.3 Back-off Time.......................................................................................................................................60 9.3.4.4 Reset of the Back-off Timer..................................................................................................................60 9.3.5 File Repair Server Selection.......................................................................................................................60 9.3.5.1 List of Server URIs...............................................................................................................................60 9.3.5.2 Selection from the Server URI List.......................................................................................................60 9.3.6 File Repair Request Message......................................................................................................................60 9.3.6.1 File Repair Request Message Format....................................................................................................61 9.3.7 File Repair Response Message...................................................................................................................62 9.3.7.1 File Repair Response Messages Codes.................................................................................................63 9.3.7.2 File Repair Response Message Format for HTTP Carriage of Repair Data..........................................63 9.3.7.3 File Repair Response for Broadcast/Multicast of Repair Data..............................................................64 9.3.8 Server Not Responding Error Case.............................................................................................................65 9.4 The Reception Reporting Procedure.................................................................................................................65 9.4.1 Identifying Complete File Reception from MBMS Download...................................................................66 9.4.2 Identifying Complete MBMS Delivery Session Reception........................................................................66 9.4.3 Determining Whether a Reception Report Is Required..............................................................................66 9.4.4 Request Time Selection..............................................................................................................................67 9.4.5 Reception Report Server Selection.............................................................................................................67 9.4.6 Reception Report Message.........................................................................................................................67 9.4.7 Reception Report Response Message.........................................................................................................68 9.5 XML-Schema for Associated Delivery Procedures.........................................................................................68 9.5.1 Generic Associated Delivery Procedure Description..................................................................................68 9.5.2 Example Associated Delivery Procedure Description Instance............................................................69 9.5.3 XML Syntax for a Reception Report Request............................................................................................69 9.5.3.1 Use of Specific Values..........................................................................................................................70 9.5.3.2 Example XML for the Reception Report Request................................................................................70 10 Media codecs and formats......................................................................................................................71 10.1 General.............................................................................................................................................................71 ETSI 3GPP TS 26.346 version 6.3.0 Release 6 6 ETSI TS 126 346 V6.3.0 (2005-12) 10.2 Speech..............................................................................................................................................................71 10.3 Audio................................................................................................................................................................71 10.4 Synthetic audio.................................................................................................................................................72 10.5 Video................................................................................................................................................................72 10.6 Still images.......................................................................................................................................................73 10.7 Bitmap graphics................................................................................................................................................73 10.8 Vector graphics................................................................................................................................................73 10.9 Text..................................................................................................................................................................73 10.10 Timed text........................................................................................................................................................74 10.11 3GPP file format...............................................................................................................................................74 11 MBMS Metadata....................................................................................................................................74 11.1 The MBMS Metadata Envelope.......................................................................................................................74 11.1.1 Supported Metadata Syntaxes.....................................................................................................................74 11.1.2 Consistency Control and Syntax Independence..........................................................................................74 11.1.3 Metadata Envelope Definition....................................................................................................................75 11.1.4 Delivery of the Metadata Envelope............................................................................................................76 11.2 MBMS User Service Description Metadata Fragment.....................................................................................76 11.2.1 Definition of the MBMS User Service Bundle Description.......................................................................76 11.2.2 Example MBMS User Service Description Instances................................................................................77 11.3 Service Protection Description Metadata Fragment.........................................................................................78 11.3.1 Definition of the Protection Description.....................................................................................................78 11.3.2 Example of a Security Description:............................................................................................................80 11.4 Service Protection Registration Format............................................................................................................80 11.4.1 Data Format................................................................................................................................................80 11.4.2 Example......................................................................................................................................................81 11.5 Service Protection De-Registration Format......................................................................................................81 11.5.1 Data Format................................................................................................................................................81 11.5.2 Example......................................................................................................................................................81 11.6 Service Protection MSK Request Format.........................................................................................................81 11.6.1 Data Format................................................................................................................................................81 11.6.2 Example......................................................................................................................................................82 Annex A (normative): FLUTE Support Requirements....................................................................83 Annex B (normative): FEC encoder specification.............................................................................85 B.1 Definitions, Symbols and Abbreviations................................................................................................85 B.1.1 Definitions........................................................................................................................................................85 B.1.2 Symbols............................................................................................................................................................86 B.1.3 Abbreviations...................................................................................................................................................87 B.2 Overview................................................................................................................................................87 B.3 File download.........................................................................................................................................87 B.3.1 Source block construction................................................................................................................................87 B.3.1.1 General........................................................................................................................................................87 B.3.1.2 Source block and sub-block partitioning....................................................................................................88 B.3.2 Encoding packet construction...........................................................................................................................89 B.3.2.1 General........................................................................................................................................................89 B.3.2.2 Encoding packet construction.....................................................................................................................89 B.3.3 Transport..........................................................................................................................................................89 B.3.4 Example parameters.........................................................................................................................................90 B.3.4.1 Parameter derivation algorithm...................................................................................................................90 B.3.4.2 Examples....................................................................................................................................................91 B.4 Streaming...............................................................................................................................................91 B.4.1 Source block construction................................................................................................................................91 B.4.2 Encoding packet construction...........................................................................................................................91 B.4.3 Transport..........................................................................................................................................................92 B.4.4 Example parameters.........................................................................................................................................92 B.4.4.1 Parameter derivation algorithm...................................................................................................................92 B.4.4.2 Examples....................................................................................................................................................93 ETSI 3GPP TS 26.346 version 6.3.0 Release 6 7 ETSI TS 126 346 V6.3.0 (2005-12) B.5 Systematic Raptor encoder.....................................................................................................................93 B.5.1 Encoding overview...........................................................................................................................................93 B.5.2 First encoding step: Intermediate symbol Generation......................................................................................94 B.5.2.1 General........................................................................................................................................................94 B.5.2.2 Source symbol triples..................................................................................................................................94 B.5.2.3 Pre-coding relationships.............................................................................................................................94 B.5.2.4 Intermediate symbols..................................................................................................................................95 B.5.2.4.1 Definition..............................................................................................................................................95 B.5.2.4.2 Example method for calculation of intermediate symbols....................................................................95 B.5.3 Second encoding step: LT encoding.................................................................................................................97 B.5.4 Generators........................................................................................................................................................97 B.5.4.1 Random Generator......................................................................................................................................97 B.5.4.2 Degree Generator........................................................................................................................................97 B.5.4.3 LT Encoding Symbol Generator.................................................................................................................97 B.5.4.4 Triple generator..........................................................................................................................................98 B.6 Systematic Indices J(K)).........................................................................................................................99 B.7 Random Numbers.................................................................................................................................100 B.7.1 The table V ....................................................................................................................................................100 0 B.7.2 The table V ....................................................................................................................................................100 1 B.8 VOID....................................................................................................................................................100 Annex C (informative): IANA registration........................................................................................101 C.1 Registration of SDP Protocol Identifiers for Source packet.................................................................101 C.2 Registration of SDP Protocol identifier for repair packets...................................................................101 C.3 Registration of MIME type "application/simpleSymbolContainer"....................................................101 C.4 Registration of MIME type "application/mbms-user-service-description+xml "................................102 C.5 Registration of MIME type "application/mbms-envelope+xml "........................................................103 C.6 Registration of MIME type "application/mbms-protection-description+xml "....................................105 C.7 Registration of MIME type "application/mbms-associated-procedure-description+xml"...................106 C.8 Registration of MIME type "application/mbms-msk+xml".................................................................107 C.9 Registration of MIME type "application/mbms-register+xml"............................................................108 C.10 Registration of MIME type "application/mbms-deregister+xml"........................................................109 C.11 Registration of MIME type "application/mbms-reception-report+xml"..............................................110 Annex D (informative): RTP packetization guidelines.....................................................................112 Annex E (informative): Example FEC decoder.................................................................................113 E.1 General...........................................................................................................................................................113 E.2 Decoding a source block................................................................................................................................113 E.2.1 General......................................................................................................................................................113 E.2.2 First Phase.................................................................................................................................................114 E.2.3 Second Phase............................................................................................................................................115 E.2.4 Third Phase...............................................................................................................................................115 E.2.5 Fourth Phase.............................................................................................................................................115 Annex F (informative): Change history.............................................................................................116 History............................................................................................................................................................117 ETSI 3GPP TS 26.346 version 6.3.0 Release 6 8 ETSI TS 126 346 V6.3.0 (2005-12) 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. 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 3GPP TS 26.346 version 6.3.0 Release 6 9 ETSI TS 126 346 V6.3.0 (2005-12) 1 Scope The present document defines a set of media codecs, formats and transport/application protocols to enable the deployment of MBMS user services over the MBMS bearer service within the 3GPP system. In this version of the specification, only MBMS download and streaming delivery methods are specified. The present document does not preclude the use of other delivery methods. The present document includes information applicable to network operators, service providers and manufacturers. 2 References The following documents contain provisions which, through reference in this text, constitute provisions of the present document. • References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific. • For a specific reference, subsequent revisions do not apply. • For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document. [1] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications". [2] 3GPP TS 22.146: "Multimedia Broadcast/Multicast Service; Stage 1". [3] 3GPP TS 22.246: "Multimedia Broadcast/Multicast Service (MBMS) user services; Stage 1". [4] 3GPP TS 23.246: "Multimedia Broadcast/Multicast Service (MBMS); Architecture and functional description". [5] 3GPP TS 25.346: "Introduction of Multimedia Broadcast/Multicast Service (MBMS) in the Radio Access Network (RAN); Stage 2". [6] IETF STD 0064/RFC 3550 (July 2003): "RTP: A Transport Protocol for Real-Time Applications", H. Schulzrinne, S. Casner, R. Frederick, V. Jacobson. [7] IETF STD 0006/RFC 0768 (August 1980): "User Datagram Protocol", J. Postel. [8] IETF STD 0005/RFC 0791 (September 1981): "Internet Protocol", J. Postel. [9] IETF RFC 3926 (October 2004): "FLUTE - File Delivery over Unidirectional Transport", T. Paila, M. Luby, R. Lehtonen, V. Roca, R. Walsh. [10] IETF RFC 3450 (December 2002): "Asynchronous Layered Coding (ALC) Protocol Instantiation", M. Luby, J. Gemmell, L. Vicisano, L. Rizzo, J. Crowcroft. [11] IETF RFC 3451 (December 2002): "Layered Coding Transport (LCT) Building Block", M. Luby, J. Gemmell, L. Vicisano, L. Rizzo, M. Handley, J. Crowcroft. [12] IETF RFC 3452 (December 2002): "Forward Error Correction (FEC) Building Block", M. Luby, L. Vicisano, J. Gemmell, L. Rizzo, M. Handley, J. Crowcroft. [13] IETF RFC 3695 (February 2004): "Compact Forward Error Correction (FEC) Schemes", M. Luby, L. Vicisano. [14] IETF RFC 2327 (April 1998): "SDP: Session Description Protocol", M. Handley and V. Jacobson. ETSI