Markdown Version | Session Recording

Session Date/Time: 25 Jul 2024 16:30

quic

Summary

This QUIC working group meeting covered several key topics, including updates on Multipath QUIC (MP-QUIC), Q-log, accurate ECN acknowledgements, H3 priorities, and QUIC token handling. The MP-QUIC discussion focused on resolving open design issues and outlining remaining editorial work. The Q-log presentation highlighted recent changes related to extensibility and solicited feedback on the proposed architecture. Discussions on accurate ECN acknowledgements centered on the benefits and drawbacks of encoding detailed ECN marking information in ACK frames. Finally, the issue of handling new tokens across multiple CDNs was raised, leading to discussion about potential solutions and the need for clarification in the specification.

Key Discussion Points

• MP-QUIC:
  • Renaming MP frames to use "pass" prefix instead of "MP".
  • Renaming "pass standby" to "pass backup".
  • Clarifying the interaction between disabled active migration and multipath. Specifically, migration is disabled on pass zero.
  • Debating whether MP-specific frames (ACK, CID retirement, new CID) should be mandatory for pass zero. The group reached a consensus of 'should', not 'must'.
  • Providing guidance on the use of multiple paths on the same 4-tuple.
  • Removing the multipath-specific protocol violation error code.
  • Removing the error code from the pass abandon frame.
  • Adding a Max Pass Blocked (renamed to Path Blocked) frame to explicitly signal limits.
  • Determining whether the sequence number in Pass Standby and Pass Available frames should be connection-wide or per-path. No change was decided.
  • Discussing if tokens can be used on any pass.
  • Removing the section on refusing a pass challenge.
  • Defining behavior on idle timeout for multipath connections, deciding to remove the sentence and provide better explanation.
  • Defining the handling of packets received on an unused pass ID. Change "must" to "should".
• Q-log:
  • Using media types in the serialization format field.
  • Adding a new form of prefix for event extensions.
  • Discussing how to handle clocks for inter-device time logging.
• Accurate ECN Acknowledgements:
  • Discussing the benefit of a new ACK frame to encode precise ECT markings.
  • Concerns were raised about size increase due to random patterns.
  • ECN mark ratio suggestion.
• QUIC Tokens:
  • Addressing the issue of new tokens generated by one CDN being used on another.
  • Discussion regarding existing code which rejects those tokens.

Decisions and Action Items

• MP-QUIC:
  • Rename MP frames to use "pass" prefix.
  • Rename "pass standby" to "pass backup".
  • Use "should" for MP-specific frames on pass zero, instead of "must".
  • Remove the multipath-specific protocol violation error code.
  • Remove the error code from the pass abandon frame.
  • Add a Path Blocked frame.
  • No change to sequence number for Pass Standby and Pass Available frames.
  • Remove the section on refusing a pass challenge.
  • Remove the sentence and provide better explanation about idle timeout for multipath connections.
  • Change the "must" for address validation on a new path to "should".
  • Mia and Yama to work on editorial updates and consider an interim meeting if significant design issues arise.
• Q-log:
  • Lucas to create a proposal and bring it back to the list on handling the clocks for inter-device time logging.
• Accurate ECN Acknowledgements:
  • Authors to discuss offline, experiment further, and reflect back on the list.
• QUIC Tokens:
  • Mike to follow up with the raised Narotum.

Next Steps

• Authors to address action items and feedback from the meeting.
• Encourage wider review and implementation of the MP-QUIC and Q-log drafts.
• Continue discussion on open issues on the mailing list.
• Consider an interim meeting for MP-QUIC if necessary.