1、 ETSI TR 126 938 V14.0.0 (2017-04) Universal Mobile Telecommunications System (UMTS); LTE; Packet-switched Streaming Service (PSS); Improved support for dynamic adaptive streaming over HTTP in 3GPP (3GPP TR 26.938 version 14.0.0 Release 14) TECHNICAL REPORT ETSI ETSI TR 126 938 V14.0.0 (2017-04)13GP
2、P TR 26.938 version 14.0.0 Release 14Reference RTR/TSGS-0426938ve00 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 but non lucratif enregistre la Sous-Prfecture de
3、Grasse (06) N 7803/88 Important notice The present document can be downloaded from: http:/www.etsi.org/standards-search The present document may be made available in electronic versions and/or in print. The content of any electronic and/or print versions of the present document shall not be modified
4、 without the prior written authorization of ETSI. In case of any existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat. Users
5、 of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at https:/portal.etsi.org/TB/ETSIDeliverableStatus.aspx If you find errors in the present document, please send y
6、our comment to one of the following services: https:/portal.etsi.org/People/CommiteeSupportStaff.aspx Copyright Notification No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm except as authorized by written permission of
7、 ETSI. The content of the PDF version shall not be modified without the written authorization of ETSI. The copyright and the foregoing restriction extend to reproduction in all media. European Telecommunications Standards Institute 2017. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTMand the ETSI l
8、ogo 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 ETSI TR 126 938 V14.
9、0.0 (2017-04)23GPP TR 26.938 version 14.0.0 Release 14Intellectual 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 c
10、an 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 (https:/ipr.etsi.org/). Pursuant to the ET
11、SI 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. Forewor
12、d This Technical Report (TR) 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
13、 ETSI deliverables. The cross reference between GSM, UMTS, 3GPP and ETSI identities can be found under http:/webapp.etsi.org/key/queryform.asp. Modal verbs terminology In the present document “should“, “should not“, “may“, “need not“, “will“, “will not“, “can“ and “cannot“ are to be interpreted as d
14、escribed in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of provisions). “must“ and “must not“ are NOT allowed in ETSI deliverables except when used in direct citation. ETSI ETSI TR 126 938 V14.0.0 (2017-04)33GPP TR 26.938 version 14.0.0 Release 14Contents Intellectual Prop
15、erty Rights 2g3Foreword . 2g3Modal verbs terminology 2g3Foreword . 8g3Introduction 8g31 Scope 9g32 References 9g33 Definitions and abbreviations . 10g33.1 Definitions 10g33.2 Abbreviations . 11g34 Relevant Specifications 12g34.1 Overview 12g34.2 3GP-DASH as a profile of MPEG-DASH . 12g34.2.1 General
16、 12g34.2.2 Media Codecs . 13g34.2.3 Media Presentation Description constraints 13g34.2.4 Segment format constraints 13g34.2.5 Extensions . 13g34.2.5.1 Media Presentation Description Delta . 13g35 Deployment Guidelines 15g35.1 Introduction 15g35.2 Content Authoring Guidelines 15g35.3 Client implement
17、ation and client operation guidelines 15g35.3.1 Guidelines for rate adaptation . 15g35.3.1.1 Introduction . 15g35.3.1.2 Rate adaptation in DASH 15g35.4 Operational and deployment guidelines . 16g35.4.1 General 16g35.4.2 Proxy/cache switch for DASH service 16g35.4.2.1 Assumptions 16g35.4.2.2 Descript
18、ion 16g35.4.2.3 Working assumption . 16g35.4.2.4 Recommended Requirements 17g36 General Use Cases 17g36.1 Introduction 17g36.2 Advanced Support for Live Services 17g36.2.1 Description 17g36.2.1.1 Setup . 17g36.2.1.2 Use Case A: Start-up latency 17g36.2.1.3 Use Case B: Aligned Presentation 17g36.2.1.
19、4 Use Case C: End-to-end latency 17g36.2.1.5 Use Case D: Time-Shift Buffer . 17g36.2.1.6 Use Case E: Infrastructure Upgrade 17g36.2.1.7 Use Case F: Ad Insertion 17g36.2.2 Operation with MPD dynamic Mode 18g36.2.2.1 Introduction . 18g36.2.2.2 Problem Statement 18g36.2.2.3 Existing Technologies. 18g36
20、.2.2.4 Consequences with Existing Technologies . 18g36.2.2.5 How does DASH solve this? . 19g36.2.2.5.1 Overview . 19g36.2.2.5.2 Benefits of this approach . 19g3ETSI ETSI TR 126 938 V14.0.0 (2017-04)43GPP TR 26.938 version 14.0.0 Release 146.2.2.6 MPD Times . 20g36.2.2.7 General Derivation 20g36.2.2.
21、8 Derivation of MPD Times . 21g36.2.2.9 Addressing Methods 21g36.2.2.9.1 Introduction . 21g36.2.2.9.2 Playlist-Method . 21g36.2.2.9.3 Number-Based Template . 21g36.2.2.10 Scheduling Playout 21g36.2.2.11 Validity of MPD 22g36.2.3 Mapping Use Cases to Live Operation . 22g36.2.3.1 Use Case A 22g36.2.3.
22、1.1 Description 22g36.2.3.1.2 MPD example 22g36.2.3.1.3 Client Procedure 22g36.2.3.2 Use Case B 23g36.2.3.2.1 Description 23g36.2.3.2.2 MPD example 23g36.2.3.2.3 Client Procedure 23g36.2.3.3 Use Case C 23g36.2.3.3.1 Description 23g36.2.3.3.2 MPD example 23g36.2.3.3.3 Client Procedure 23g36.2.3.4 Use
23、 Case D 23g36.2.3.4.1 Description 23g36.2.3.4.2 MPD example 24g36.2.3.4.3 Client Procedure 24g36.2.3.5 Use Case E 24g36.2.3.5.1 Description 24g36.2.3.5.2 MPD example 24g36.2.3.5.3 Client Procedure 25g36.2.3.6 Use Case F 25g36.2.3.6.1 Description 25g36.2.3.6.2 MPD example 25g36.2.3.6.3 Client Procedu
24、re 25g36.2.4 Gap Analysis. 25g36.2.5 Working Assumptions 26g36.3 Use Cases for Content Protection . 26g36.3.1 Use Case A Efficient Caching for Multiple DRM Systems . 26g36.3.1.1 Description 26g36.3.1.2 Actors issues . 26g36.3.1.3 Analysis in the Context of Rel-10 TS 26.247 . 26g36.3.2 Use Case B Sig
25、nalling of Rights/License Acquisition Information in MPD . 27g36.3.2.1 Description 27g36.3.2.2 Actors issues: 27g36.3.2.3 Analysis in the Context of Rel-10 TS 26.247 . 27g36.3.3 Use Case C Time-Varying Decryption Keys . 28g36.3.3.1 Description 28g36.3.3.2 Actors issues: 28g36.3.3.3 Analysis in the C
26、ontext of Rel-10 TS 26.247 2 28g36.4 Fast Media Start-up 29g36.4.1 Description 29g36.4.2 Analysis in the Context of Rel-10 TS 26.247 . 29g36.5 Advanced Trick Modes 29g36.5.1 Description 29g36.5.2 Analysis in the Context of MPEG-DASH and Rel-10 TS 26.247 29g36.5.2.1 Overview . 29g36.5.2.2 Sub-Represe
27、ntations 30g36.5.2.3 MPD authoring 30g36.5.2.4 Segment generation . 30g36.5.2.5 Summary . 32g36.6 Content and Device Interoperability. 32g36.6.1 Use Case Description 32g3ETSI ETSI TR 126 938 V14.0.0 (2017-04)53GPP TR 26.938 version 14.0.0 Release 146.6.2 Working Assumption 33g36.6.3 Gap Analysis . 3
28、3g36.7 Advanced Support for Live Services 33g36.7.1 Description 33g36.7.2 Working Assumption 33g36.7.3 Gap Analysis . 33g36.8 Consistent QoE/QoS for DASH users 33g36.8.1 Description 33g36.8.2 Proposed Work . 34g36.8.3 Utilization of QoS Information in DASH . 34g36.9 DASH as download format 35g36.9.1
29、 Description 35g36.10 Use Case: Use case description for Efficiency of HTTP-caching infrastructure on DASH . 37g36.10.1 Description 37g36.11 Use Case: Multiple Spectator Views offered with DASH 39g36.11.1 Description 39g36.11.2 Gap Analysis . 39g36.11.2.1 File support for timed position/location 39g
30、36.11.2.2 MPD indication of position/orientation for a Representation or Segment 41g36.11.2.3 Synchronization of media content from different devices . 42g36.11.2.4 MPD indication of key highlights of the event . 42g36.11.2.5 MPD indication of capturing parameters 42g36.12 Use cases for operator con
31、trol of video streaming services 43g36.12.1 Introduction. 43g36.12.2 Description 43g36.12.2.1 Operator control of video services 43g36.12.2.2 Operator control using mobile network subscription 43g36.12.2.3 Operator management of video streaming service over the radio network . 43g36.12.3 Working ass
32、umptions . 43g36.12.4 Conclusions and Gap Analysis 44g36.13 Use Cases for DASH Operation with Network Proxy Caches . 44g36.13.1 Introduction. 44g36.13.2 Use Case Description 44g36.13.2.1 Use Case 1: Fast Startup . 44g36.13.2.2 Use Case 2: Partial Representation Caching . 45g36.13.2.3 Use Case 3: Net
33、work mobility 45g36.13.2.4 Use Case 4: Mobility and Coverage Extension for MBMS-based service 45g36.13.3 Solution Analysis: Usage of TS 26.247 45g36.13.3.1 MPD Update . 45g36.13.3.2 Redirections 46g36.13.3.3 Bandwidth Throttling 47g36.13.3.4 Control Events . 48g36.13.3 Gap Analysis and Problem State
34、ment . 49g36.14 Services with caching of DASH content at UE functions 50g36.14.1 Use Case Description 50g36.14.1.1 Use case 1: HTTP Proxy Cache in UE for transparent reception of DASH content over unicast or broadcast . 50g36.14.1.2 Use case 2: HTTP Proxy Cache in a home GW (gateway), capable of ser
35、ving multiple DASH players in the home . 50g36.14.1.3 Use case 3: Pre-Caching on UE 50g36.14.2 Working assumptions . 51g36.14.3 Gap Analysis . 51g36.14.4 Recommended Requirements . 51g36.15 Handling special content 52g36.15.1 Description 52g36.15.1.1 Enabling users to skip some repetitive/low import
36、ance content . 52g36.15.1.2 Preventing users from skipping special content 52g36.15.1.3 Network/Content provider control of special content . 52g36.15.2 Working assumptions . 52g36.15.3 Analysis against TS 26.247: Dynamic Services . 52g36.15.3.1 General 52g36.15.3.2 Tools and Evidence . 53g3ETSI ETS
37、I TR 126 938 V14.0.0 (2017-04)63GPP TR 26.938 version 14.0.0 Release 146.15.3.3 Just-in-Time Content Insertion 53g36.15.3.4 Client Behaviour . 54g36.15.3.5 More complex rules. 54g36.15.3.6 Addressing the Use Cases . 54g36.15.3.6.1 Repetitive Content . 54g36.15.3.6.2 Forced Play-out . 54g36.15.3.6.3
38、Flexible Ad Insertion . 55g36.15.3.4 Gap Analysis and Recommendations . 57g36.16 Use Cases on DASH Authentication 57g36.16.1 Use Case 1 57g36.16.2 Use Case 2 57g36.16.3 Use Case 3 58g36.16.4 Use Case 4 58g36.16.5 Use Case 5 58g36.16.6 Gap Analysis on the Use Cases 58g36.16.6.1 Analysis of Use Cases
39、1-3 on content access authorization 58g36.16.6.2 Analysis of Use Cases 4-5 on application-level content/metadata integrity validation: . 59g36.17 Consistent Quality for DASH users 59g36.17.1 Use Case Description 59g36.17.2 Gap Analysis . 59g36.17.3 Overview of Potential Solution Space 60g36.17.4 Add
40、itional Simulation Results on DASH over GBR and Non-GBR bearers 61g37 Advertisement Insertion Use Cases 63g37.1 Introduction 63g37.2 Use Cases . 63g37.2.1 Use Case 1: Fixed duration advertisement in On-Demand Content . 63g37.2.2 Use Case 2: Variable duration advertisement in On-Demand Content . 64g3
41、7.2.3 Use Case 3: Trusted Client Playback 64g37.2.4 Use Case 4: Advertisement in Live Content . 64g37.2.5 Use Case 5: Accessing Live Content 64g37.3 Working Assumptions 64g37.3.1 Introduction. 64g37.3.2 Generic assumptions . 64g37.3.3 Single Media Presentation 65g37.3.4 Presentation Layer controlled
42、 Ad Insertion . 65g37.4 Analysis in the Context of TS 26.247. 65g37.4.1 Single Media Presentation 65g37.4.2 Presentation Layer controlled Ad Insertion Analysis . 70g37.4 Examples 72g37.4.1 Fixed Duration in On-Demand . 72g37.4.2 Targeted Advertisements 72g37.4.3 Example call for Ad insertion for DAS
43、H 74g37.6 Advanced Advertisement insertion in the operator network 75g37.6.1 Description 75g37.6.1.1 Advertisement insertion based on user subscription . 75g37.6.1.2 Targeted advertisement insertion 75g37.6.1.3 Bandwidth-related advertisement/message . 75g37.6.2 Working assumptions . 75g37.6.3 Solut
44、ion based on TS 26.247 and Gap Analysis . 75g38 Conclusions and Recommendations . 76g3Annex A: Detailed Performance Evaluation Results on Quality-Driven Rate Adaptation Algorithms . 78g3A.1 Introduction 78g3A.2 Simulation Setup 78g3A.3 Content Preparation 79g3A.4 DASH Rate Adaptation Algorithms . 81
45、g3A.4.1 Adaptation based on per-segment bitrate information (Non-Quality): . 81g3A.4.2 Adaptation based on per-segment bitrate and quality information (Quality-based) . 82g3ETSI ETSI TR 126 938 V14.0.0 (2017-04)73GPP TR 26.938 version 14.0.0 Release 14A.4.3 Bandwidth Model . 83g3A.4.4 Experimental R
46、esults 84g3Annex B: Evaluation of QoS-Driven DASH Client Adaptation 87g3Annex C: Change history 97g3History 98g3ETSI ETSI TR 126 938 V14.0.0 (2017-04)83GPP TR 26.938 version 14.0.0 Release 14Foreword This Technical Report has been produced by the 3rdGeneration Partnership Project (3GPP). The content
47、s 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:
48、 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 t
49、he third digit is incremented when editorial only changes have been incorporated in the document. Introduction 3GPPs Dynamic Adaptive Streaming over HTTP (DASH) specifications were developed in Rel-9 and Rel-10 and are available in TS 26.247 2. Despite being integrated into the PSS architecture, the specifications have significant flexibility for deployments also outside the 3GPP services. This has been recognized by other organizations such as MPEG and Open IPTV Forum. In continuous alignment efforts, 3GPP and MPEG have developed a generic format for Dynamic Ad
