Brief report from SA#110 on SA4 topics
Meeting Details:
- SA#110 took place 9-12 December 2025, hosted by ATIS in Baltimore, US
- SA4 Chair: Gilles Teniou (Tencent/CCSA)
- Report presented at SA4#135 in Goa, India (9-13 February 2026)
The SA4 report to SA#110 was noted. Key approvals included:
- All SA4 CRs (Rel-12, Rel-17, Rel-18, Rel-19) were approved
- Draft TS 26.251 V2.0.0 (IVAS_Codec_Ph2) was approved
- IVAS verification test lab reports were approved
- SA4 chair input on WG Terms of Reference was sent back to SA4 for further discussion
Workload Concerns:
- Verizon raised concerns about SA4's capacity given the large number of proposed TRs, citing slow progress on FS_ULBC
- SA4 Chair clarified that slow progress was due to dependencies and related issues, not workload
- TSG SA Chair requested companies to prepare contributions on workload issues rather than raising them in the Chair report
ToR and AI Work:
- MediaTek commented on the postponed SA4 ToR and emphasized the need to progress AI-related studies
- TSG SA Chair indicated that SA4 ToR requires consensus within SA4 before TSG SA approval
6G Planning:
- TSG SA Chair requested information on 6G planning for the next TSG SA meeting
All test lab reports for IVAS Characterization Phase were approved:
- MESAQIN.com Listening Lab Report (SP-251447)
- FORCE Technology Listening Lab Report (SP-251448)
- Global analysis lab report
Terminal Audio Quality Performance and Test Methods (SP-251352)
- Status: Approved
1. Study on Evaluation of QUIC-based Protocols for On-demand and Live Video Services (FS_QStream-MED) - SP-251353
- Status: Approved (revised to SP-251659)
- Allocated TR numbers: TR 26.835 and TR 26.934
2. IMS Data Channel Enhancements (SP-251354)
- Status: Approved (revised to SP-251660)
- Allocated TR number: TR 26.814
3. QUIC-based Media Delivery for Real-time Communication (FS_Q4RTC-MED) - SP-251355
- Status: Approved (revised to SP-251661)
- Allocated TR number: TR 26.836
- Clarification: Focused on 5G but will consider new aspects introduced by 6G
4. Study on Image Formats (SP-251356)
- Status: Approved (revised to SP-251662)
- Allocated TR number: TR 26.892
5. Study on Avatar Communication Phase 2 (SP-251357)
- Status: Approved (revised to SP-251663)
- Revision: Removed repeated supporting company
6. Study on Media Aspects for 6G System (SP-251620)
- Status: Approved (revised to SP-251652)
- Allocated TR number: TR 26.870
- Rapporteurs:
- Primary: Thomas Stockhammer (Qualcomm) - coordination of the study
- Secondary: Elmira Ramazanirend (Vodafone) - Draft TR edition
- Key Revisions:
- AN and Others impacts changed to "Don't Know"
- SA5 included for charging and management impacts
- SA1 included in objective 6 for service requirements
- Additional supporting companies added
- Non-3GPP member removed
Draft TS 26.251 v2.0.0 - IVAS Codec Phase 2 (SP-251444)
- Status: Approved (Rel-19)
- Contains fixed-point C code of the IVAS codec as electronic attachment (IVAS Software Version 3.0)
- Provides full and bit-exact EVS codec functionality for mono speech/audio signal input
- Optimized for encoding/decoding of stereo and immersive audio formats including:
- Multi-channel audio (5.1, 5.1.2, 5.1.4, 7.1, 7.1.4)
- Scene-based audio (Ambisonics up to order 3)
- Metadata-assisted spatial audio (MASA)
- Object-based audio (ISM up to 4 ISMs)
- Combined formats: OSBA and OMASA
- Supports rendering including binaural rendering for headphones with head-tracking
EVS_Codec CRs (SP-251429)
- 8 CRs to TS 26.445 (Rel-12)
- Status: Approved
- Note: Huawei commented that CRs to old frozen releases should be discouraged and only accepted for real FASMO corrections
- These CRs corrected references to other clauses
All other SA4 CRs:
- All Rel-17, Rel-18, and Rel-19 CRs submitted for approval were approved as is
- Admin CRs on TS 26.512 were approved
Incoming LS from GSMA NG UPG (SP-251301)
- Status: Noted
- SA4 Response (SP-251622, revised to SP-251693): Approved
- Issue: Ambiguity in handling external resource access in IMS Data Channel applications
- SA4 Position:
- Acknowledged gaps in current TS 26.114 specification
- Originally assumed DCSF and DC AS would be exclusive hosts for all content
- Did not anticipate scenarios involving external resources
- Plans to study this issue and provide clarifications as part of DC Enhancements (FS_DCE_MED) study in Release 20
Incoming LS from RAN WG1 (SP-251304)
- Status: Noted (SA in CC)
- SA4 recognizes importance of defining traffic models reflecting realistic traffic characteristics
- SA4 will provide input as work progresses for AI/ML Services and immersive communication services
1. IVAS_Codec_Ph2 (SP-251375)
- Source: vivo Mobile Communication Co., Ltd. (Rapporteur)
- Status: Endorsed
2. Video Operating Points - Harmonization and Stereo MV-HEVC (VOPS) - SP-251503
- Source: Apple Switzerland AG
- Status: Endorsed
Key Issue:
- Several contributions (SP-251553, SP-251499, SP-251540, SP-251576, SP-251452) attempted to structure work on identifying AI/ML data traffic characteristics, proposing SA4 as lead WG
- Concerns raised by some companies that SA4 should not be the exclusive WG for AI traffic characteristics
- Tentative way forward proposed in SP-251625 but no consensus reached
- Document was noted with no action to SA4
SA4 Chair Position:
- Work in other WGs should not interfere with SA4's planned work on AI traffic characteristics in the context of media services
- SA4 should proceed with its work, report progress to SA (and potentially RAN WGs), and let them decide applicability to other cases beyond media applications
Key Points:
- Release 21 is the release for submission to IMT-2030 (6G)
- 3GPP normative work will be submitted to ITU-R before 2030
- ASN.1/OpenAPI freeze date is no earlier than March 2029
- Previous decision: Rel-21 timeline to be decided no later than June 2026
- Some groups (SA1, RAN Plenary) will finish Rel-20 work before June 2026
Timeline Planning:
- Joint session organized at TSG#111 (March 2026) for companies to share views on Rel-21 timeline
- TSG Chairs will provide joint input paper outlining proposed Rel-21 timeline
- Some Rel-21 dates (e.g., Stage-1 freeze) may be tentatively agreed at TSG#111
- Final approval of Rel-21 timeline targeted for TSG#112 (June 2026)
- First Rel-21 SID proposed at SA#110 (from SA1)
No particular guidance was provided to SA4.
Action: SA4 will report progress and plans related to AI traffic characteristics at the next SA plenary.