Markdown Version | Session Recording

Session Date/Time: 22 Jan 2026 17:00

AVTCORE

Summary

This AVTCORE interim virtual meeting focused on updates for three key drafts: draft-ietf-avtcore-s-frame, draft-ietf-avtcore-rtcp-temporal-spatial-resolution (Green Metadata), and draft-ietf-avtcore-rtp-over-quic. Key discussions included the integration of S-Frame with the Matter specification, the call for a second Working Group Last Call (WGLC) for the green metadata draft, and the ongoing development of RTP over QUIC, including a new sub-draft for ICE negotiation.

Key Discussion Points

• S-Frame Status (draft-ietf-avtcore-s-frame)

  • Aaron Rosenberg provided an update on the draft, noting its importance for Matter camera standardization, which will adopt S-Frame for all cameras.
  • The latest draft proposes:
    • An updated packetization header supporting per-frame and per-packet S-Frame cryptography.
    • A new SDP attribute for S-Frame negotiation, indicating offer and acceptance.
    • A key derivation algorithm to generate individualized keys per SSRC (M-Line in WebRTC) from a single master key, ensuring cryptographic isolation and preventing CTR/key reuse across media streams.
  • The key derivation and ratcheting mechanisms are based on existing RFC 9605 algorithms; no new cryptography is introduced.
  • The goal is to enable direct S-Frame encryption from cameras into RTP without intermediate decryption, supporting various cipher suites and ratcheting schedules.
  • The derivation of per-stream keys was highlighted as the most complex new part of the draft for implementation.
  • An early review from the Security Directorate has already occurred.
  • It was agreed that a dedicated presentation on this draft would be beneficial at the IETF 125 meeting in Shenzhen to facilitate wider security review.

• Green Metadata (RTCP for Temporal/Spatial Resolution draft-ietf-avtcore-rtcp-temporal-spatial-resolution)

  • The latest version (V7) addresses comments from Eric and Young Guang, focusing on background, development, and primary use cases (point-to-point video conferencing for battery saving, timely session completion, and software resource allocation).
  • It corrects typos and mismatches in figures.
  • The technology for spatial/temporal resolution changes is widely deployed and supported by various SDKs (NVIDIA, WebRTC API, Microsoft Draft) and codecs (AV1, H.267VC) without significant overhead.
  • The draft aims to promote interoperability for exchanging resolution change capabilities across devices and platforms.
  • The authors requested a second WGLC.

• RTP over QUIC (SDP Offer/Answer for RTP over QUIC draft-ietf-avtcore-rtp-over-quic)

  • Spencer Dawkins provided an update, noting progress on three open pull requests (PRs) since IETF 124.
  • A PR clarifying the relationship between bundle and ROC flow was merged, defining the RTP session as equivalent to a ROC flow and bundled.
  • Discussion on changing the draft title from "SDP for RTP offer/answer over QUIC" to a more generic "SDP for RTP over QUIC" was initiated via a PR, with a suggestion to consider adding text for declarative SDP usage.
  • New work is underway to define a ROC-ICE transport protocol, potentially as a separate draft, to clarify ICE negotiation over QUIC. This aims to be similar to UDP-ICE and TCP-ICE, focusing on identifying "obvious differences" in areas like candidate selection, preferences, collection techniques, and connection initiation.
  • Outstanding issues include:
    • Specifying RTCP feedback replacement with QUIC equivalences (consensus is to gain more implementation experience first).
    • Interaction with MassGDP Connect (deferred for now).
    • Ensuring synchronization between the base ROC and SDP ROC drafts.
  • The base ROC specification (draft-ietf-avtcore-rtp-over-quic) has expired, requiring attention before IETF 125.

• AVATAR Draft Adoption Call

  • A question was raised regarding the outcome of the AVATAR draft adoption call. The chairs acknowledged this needs review.

• HEVC WebRTC

  • Fippo was expected to provide an update but was unable to attend.

• Working Group Resources

  • Chairs reminded participants about the new repository for WG materials (e.g., agendas) and the GitHub organization for housing drafts.

Decisions and Action Items

• Decision: A security directorate review for draft-ietf-avtcore-s-frame will be initiated.
• Decision: A second Working Group Last Call (WGLC) for draft-ietf-avtcore-rtcp-temporal-spatial-resolution will be initiated.
• Action Item: Chairs (Jonathan Lennox, Marius Kleidel) to initiate a security directorate review for draft-ietf-avtcore-s-frame.
• Action Item: Chairs (Jonathan Lennox, Marius Kleidel) to initiate a second WGLC for draft-ietf-avtcore-rtcp-temporal-spatial-resolution before IETF 125.
• Action Item: Spencer Dawkins to consider adding text to draft-ietf-avtcore-rtp-over-quic regarding its usage in declarative SDP mode.
• Action Item: Spencer Dawkins to notify the QUIC and AVT mailing lists when the ROC-ICE draft is ready for broader review.
• Action Item: Chairs (Jonathan Lennox, Marius Kleidel) to review the outstanding adoption call for the AVATAR draft.
• Action Item: Spencer Dawkins to address the expiration of the base ROC specification (draft-ietf-avtcore-rtp-over-quic) before IETF 125.

Next Steps

• A full presentation and discussion of draft-ietf-avtcore-s-frame at IETF 125, with an emphasis on security review.
• Proceed with the second WGLC for draft-ietf-avtcore-rtcp-temporal-spatial-resolution.
• Continue work on draft-ietf-avtcore-rtp-over-quic and the new ROC-ICE draft, soliciting feedback from relevant communities.
• Chairs to resolve the AVATAR draft adoption call.
• Participants are encouraged to utilize the new AVTCORE repository and GitHub organization for draft management.