1、 ETSI TR 1Universal Mobile TelMultimedia telephony Study on improved ehandling for Multimed(3GPP TR 26.9TECHNICAL REPORT 126 924 V13.0.1 (2017elecommunications System (LTE; y over IP Multimedia Subsysted end-to-end Quality of Servicedia Telephony Service for IM.924 version 13.0.1 Release 1317-01) (U
2、MTS); stem (IMS); ice (QoS) IMS (MTSI) 13) ETSI ETSI TR 126 924 V13.0.1 (2017-01)13GPP TR 26.924 version 13.0.1 Release 13Reference RTR/TSGS-0426924vd01 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 62
3、3 562 00017 - NAF 742 C Association but non lucratif enregistre la Sous-Prfecture de 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
4、of any electronic and/or print versions of the present document shall not be modified 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
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7、l, including photocopying and microfilm except as authorized by written permission of 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 Sta
8、ndards Institute 2017. All rights reserved. DECTTM, PLUGTESTSTM, UMTSTMand 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 a
9、re Trade Marks registered and owned by the GSM Association. ETSI ETSI TR 126 924 V13.0.1 (2017-01)23GPP TR 26.924 version 13.0.1 Release 13Intellectual Property Rights IPRs essential or potentially essential to the present document may have been declared to ETSI. The information pertaining to these
10、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 up
11、dates are available on the ETSI Web server (https:/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 se
12、rver) which are, or may be, or may become, essential to the present document. Foreword 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
13、 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. Modal verbs terminology In the present document “should“, “should not“,
14、 “may“, “need not“, “will“, “will not“, “can“ and “cannot“ are to be interpreted as described 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 126 924
15、 V13.0.1 (2017-01)33GPP TR 26.924 version 13.0.1 Release 13Contents Intellectual Property Rights 2g3Foreword . 2g3Modal verbs terminology 2g3Foreword . 7g3Introduction 7g31 Scope 8g32 References 8g33 Definitions and abbreviations . 9g33.1 Definitions 9g33.2 Abbreviations . 9g34 Overview 9g35 Current
16、 QoS reservation mechanisms during session setup . 10g35.1 System description . 10g35.2 Simple SDP negotiation and bearer setup 11g35.3 Other system aspects 12g35.4 Relationship between QoS parameters and rate adaptation 12g35.4.1 Introduction. 12g35.4.2 MBR=GBR bearer 13g35.4.3 MBRGBR bearer 13g35.
17、4.4 Different QoS settings in different networks 13g36 Use cases 14g36.1 General description. 14g36.2 Use case A: Single fixed-rate speech codec . 14g36.2.1 General description . 14g36.2.2 Gap analysis 15g36.3 Use case B: Several fixed-rate speech codecs 16g36.3.1 General description . 16g36.3.1.1 O
18、verview . 16g36.3.1.2 SDP impacts on media handling . 16g36.3.1.3 Bearer allocation based on first SDP offer/answer 17g36.3.1.4 Bearer allocation based on second SDP offer/answer . 19g36.3.2 Gap analysis after 1st SDP offer/answer . 20g36.3.2.1 Common 20g36.3.2.2 IMS-A chooses Option 1; IMS-B choose
19、s Option 1 . 20g36.3.2.3 IMS-A chooses Option 2; IMS-B chooses Option 2 . 21g36.3.2.4 IMS-A chooses Option 1; IMS-B chooses Option 2 . 21g36.3.2.5 IMS-A chooses Option 2; IMS-B chooses Option 1 . 22g36.3.2.6 Root-cause analysis when b=AS is used for resource reservation 23g36.3.2.7 Root-cause analys
20、is when codec-specific information is used for resource reservation . 24g36.3.2.8 Handling of over-allocation and under-allocation . 24g36.3.3 Gap analysis after 2nd SDP offer/answer . 24g36.4 Use case C: Single multi-rate speech codec (AMR), no extra bandwidth allocated for redundancy . 25g36.4.1 G
21、eneral description . 25g36.4.2 Gap analysis 28g36.5 Use case D: Single multi-rate speech codec (AMR) with extra bandwidth allocated for redundancy . 28g36.5.1 General description . 28g36.5.2 Gap analysis 30g36.6 Use case E: Several multi-rate speech codecs (AMR and AMR-WB) . 30g36.6.1 General descri
22、ption . 30g36.6.2 Gap analysis 31g36.7 Use case F: Single video codec, symmetric usage . 32g3ETSI ETSI TR 126 924 V13.0.1 (2017-01)43GPP TR 26.924 version 13.0.1 Release 136.7.1 General description . 32g36.7.2 Gap analysis 33g36.7.3 Root-cause analysis. 35g36.8 Use case G: Single video codec, asymme
23、tric usage, sending video with a bitrate matching the codec level 35g36.8.1 General description . 35g36.8.2 Gap analysis 36g36.8.3 Root-cause analysis. 36g36.9 Use case H: Single video codec, asymmetric usage, sending video with a bitrate lower than the supported codec level . 37g36.9.1 General desc
24、ription . 37g36.9.2 Gap analysis 38g36.9.3 Root-cause analysis. 38g36.10 Use case I: Multiple video codecs 39g36.10.1 General description . 39g36.10.2 Gap analysis 41g36.10.3 Root-cause analysis. 41g36.11 Use case J: Single video codec, symmetric usage, bitrate variations . 41g36.11.1 General descri
25、ption . 41g36.11.2 Gap analysis 46g36.12 Use case K: Several multi-rate speech codecs (AMR, AMR-WB and EVS), small difference in EVS usage between operators . 46g36.12.1 General description . 46g36.12.2 Gap analysis 47g36.13 Use case L: Several multi-rate speech codecs (AMR, AMR-WB and EVS), large d
26、ifference in EVS usage between operators . 47g36.13.1 General description . 47g36.13.2 Gap analysis 48g37 Recommended requirements 48g37.1 Discussion on individual recommended requirements . 48g37.1.1 General 48g37.1.2 Use case A: Single fixed-rate speech codec 48g37.1.3 Use case B: Several fixed-ra
27、te speech codecs. 48g37.1.4 Use case C: Single multi-rate speech codec (AMR), no extra bandwidth allocated for redundancy 49g37.1.5 Use case D: Single multi-rate speech codec (AMR) with extra bandwidth allocated for redundancy 50g37.1.6 Use case E: Several multi-rate speech codecs (AMR and AMR-WB) .
28、 50g37.1.7 Use case F: Single video codec, symmetric usage 50g37.1.8 Use case G: Single video codec, asymmetric usage, sending video with a bitrate matching the codec level 50g37.1.9 Use case H: Single video codec, asymmetric usage, sending video with a bitrate lower than the supported codec level 5
29、1g37.1.10 Use case I: Multiple video codecs 51g37.1.11 Use case J: Single video codec, symmetric usage, bitrate variations 51g37.1.12 Use case K: Several multi-rate speech codecs (AMR, AMR-WB and EVS), small difference in EVS usage between operators . 51g37.1.13 Use case L: Several multi-rate speech
30、 codecs (AMR, AMR-WB and EVS), large difference in EVS usage between operators . 52g37.2 Discussion on proposed requirements for new SDP attributes . 52g37.3 Discussion on proposed general requirements for the solution 52g37.4 Summary of proposed requirements . 53g37.5 Definition of new bandwidth in
31、formation parameters 54g37.5.1 Overview 54g37.5.2 Maximum Supported Bandwidth 54g37.5.3 Maximum Desired Bandwidth 54g37.5.4 Minimum Desired Bandwidth. 55g37.5.5 Minimum Supported Bandwidth. 55g38 Potential solution(s) 55g38.1 Potential solution A: Session re-negotiation 55g38.1.1 Introduction. 55g38
32、.1.2 Description of the solution 56g3ETSI ETSI TR 126 924 V13.0.1 (2017-01)53GPP TR 26.924 version 13.0.1 Release 138.1.3 Compliance with proposed requirements 56g38.1.4 Impact on networks and terminals 56g38.2 Potential solution B: New bandwidth modifiers in SDP offer and answer without SDP MiscCap
33、Neg . 57g38.2.1 Introduction. 57g38.2.2 Description of the solution 57g38.2.2.1 General solution 57g38.2.2.2 New bandwidth modifiers . 57g38.2.2.3 Procedures . 58g38.2.2.4 Session negotiation example . 58g38.2.2.5 Modifying the bandwidth information in the SDP offer . 60g38.2.2.6 Resource reservatio
34、n in different networks . 60g38.2.3 Compliance with proposed requirements 61g38.2.4 Impact on networks and terminals 61g38.3 Potential solution C: New bandwidth modifiers and SDPMiscCapNeg in SDP offer and answer . 61g38.3.1 Introduction. 61g38.3.2 Description of the solution 61g38.3.2.1 General sol
35、ution 61g38.3.2.2 Procedures . 62g38.3.2.3 Session negotiation example . 62g38.3.2.4 Modifying the bandwidth information in the SDP offer . 63g38.3.2.5 Resource reservation in different networks . 64g38.3.3 Compliance with proposed requirements 64g38.3.4 Impact on networks and terminals 64g38.4 Pote
36、ntial solution D: New attribute for bandwidth information in SDP offer and answer for each RTP payload type . 65g38.4.1 Introduction. 65g38.4.2 Description of the solution 65g38.4.2.1 General solution 65g38.4.2.2 New attribute . 65g38.4.2.3 Procedures. 66g38.4.2.4 Session negotiation example . 66g38
37、.4.2.5 Modifying the bandwidth information in the SDP offer . 66g38.4.2.6 Resource reservation in different networks . 67g38.4.3 Compliance with proposed requirements 67g38.4.4 Impact on networks and terminals 67g38.5 Potential solution E: New bandwidth modifiers only in SDP answer 67g38.5.1 Introdu
38、ction. 67g38.5.2 Description of the solution 67g38.5.2.1 General solution 67g38.5.2.2 New bandwidth modifiers . 67g38.5.2.3 Session negotiation example . 67g38.5.2.4 Modifying the bandwidth information in the SDP offer . 68g38.5.2.5 Resource reservation in different networks . 68g38.5.3 Compliance w
39、ith proposed requirements 68g38.5.4 Impact on networks and terminals 68g38.6 Potential solution F: New SDP attribute in SDP offer and answer for entire media line . 68g38.6.1 Introduction. 68g38.6.2 Description of the solution 68g38.6.2.1 General solution 68g38.6.2.2 New SDP attribute 69g38.6.2.3 Pr
40、ocedures. 69g38.6.2.4 Session negotiation example . 69g38.6.2.5 Modifying the bandwidth information in the SDP offer . 69g38.6.2.6 Resource reservation in different networks . 70g38.6.3 Compliance with proposed requirements 70g38.6.4 Impact on networks and terminals 70g38.7 Potential solution G: New
41、 SDP attribute only in SDP answer . 70g38.7.1 Introduction. 70g38.7.2 Description of the solution 70g38.7.2.1 General solution 70g38.7.2.2 New SDP attribute 71g38.7.2.3 Procedures. 71g3ETSI ETSI TR 126 924 V13.0.1 (2017-01)63GPP TR 26.924 version 13.0.1 Release 138.7.2.4 Session negotiation example
42、. 71g38.7.2.5 Modifying the bandwidth information in the SDP offer . 71g38.7.2.6 Resource reservation in different networks . 71g38.7.3 Compliance with proposed requirements 71g38.7.4 Impact on networks and terminals 72g38.8 Potential solution H: Bitrate variations 72g38.8.1 Introduction. 72g38.8.2
43、Description of the solution 72g38.8.3 Compliance with proposed requirements 73g38.8.4 Impact on networks and terminals 73g39 Conclusion and recommendations 73g3Annex A: Determining suitable averaging window length . 74g3A.1 Introduction 74g3A.2 Suitable averaging window for video . 74g3A.2.1 Reasona
44、ble video encoder configuration 74g3A.2.2 Normal transmission. 74g3A.2.3 Sending a large I frame 75g3A.2.4 Compensating for a large I frame . 75g3A.2.5 Sending an even larger I frame . 76g3A.2.6 Using a longer averaging window 77g3A.2.7 Selection of averaging window length . 77g3A.3 Other services .
45、 78g3A.3.1 Conversational speech using EVS VBR . 78g3A.3.2 Streaming and other non-conversational services 78g3Annex B: Change history 80g3History 81g3ETSI ETSI TR 126 924 V13.0.1 (2017-01)73GPP TR 26.924 version 13.0.1 Release 13Foreword This Technical Report has been produced by the 3rdGeneration
46、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
47、 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 enhan
48、cements, corrections, updates, etc. z the third digit is incremented when editorial only changes have been incorporated in the document. Introduction Multimedia Telephony for IMS (MTSI) is a standardized service for conversational telephony, TS 22.173 2. The media handling and interaction are specif
49、ied in TS 26.114 3. MTSI has been specified such that the user experience of multimedia telephony is equivalent to or better than corresponding circuit-switched telephony services while still having efficient resource usage. Multimedia telephony also exploits the richer capabilities of IMS where media components can be used symmetrically or asymmetrically in different directions. ETSI ETSI TR 126 924 V13.0.1 (2017-01)83GPP TR 26.924 version 13.0.1 Release 131 Scope TS 26.114 define media handling and interaction for the Multimedia Telephony Service for IMS (MTSI) includin
