Markdown Version | Session Recording
Session Date/Time: 05 Nov 2024 13:00
# tcpm
## Summary
The TCPM working group meeting covered the status of several drafts, including PRR, Accurate ECN, TCP EDO, and the TCP Act Request draft. Presentations were given on each document, with discussion focusing on open issues, proposed resolutions, and implementation considerations. A side meeting was announced to discuss a new socket option for minimizing delay in TCP and QUIC.
## Key Discussion Points
* **PRR (Proportional Rate Reduction):**
* Clarified that PRR can be used with Reno and Cubic congestion control.
* Discussed how and when to reduce SS Thresh in loss recovery. The consensus was to separate the concerns of the congestion control algorithm and PRR.
* Proposed to redefine the term "pipe" as "in-flight" data to be more generic.
* **Accurate ECN:**
* No major updates, awaiting AD review and feedback.
* **Improving the Validation of the ACK field in packets:**
* The presentation explained how to improve the check on the acknowledgement number to detect replay attacks.
* The solutions should be working. The plan is to do the editorial stuff to or have the editorial cleaner to do some editorial cleanup by the next IETF and then go to working group line call.
* **TCP EDO (Extended Data Offset):**
* Implementation feedback from Kunyuki Iwasima highlighted unclear points in the draft, which have been addressed in version 14.
* Concerns were raised about disabling GSO and GRO when using EDO.
* Discussion about extending the option space for SYN segments.
* The group struggled to resurrect the document which has been around for a very long time.
* It seems there is no workload and therefore no energy in the WG.
* **TCP Act Request (TAR) Option:**
* Addressed comments from the previous meeting regarding retransmission timer expiration.
* Concerns were raised about sparse acts inflicting burstiness on other flows. The discussion centered on pacing requirements and ensuring acts are sent frequently enough (e.g., at least once per millisecond).
* **New Socket Option (Not Sent Low Watermark):**
* A side meeting was announced to discuss adding a new socket option that will allow for minimizing delay in TCP and QUIC.
## Decisions and Action Items
* **PRR:** Neil Cardwell will post a revision of the PRR draft incorporating the proposed edits regarding SS Thresh reduction and the "in-flight" data definition.
* **TCP EDO:** After a poll it was decided not to proceed with TCP EDO.
* **TCP Act Request:** The presenter will incorporate feedback regarding pacing and burstiness into the next revision.
* **New Socket Option:** Interested parties were invited to attend the side meeting on Thursday to discuss the proposed socket option.
## Next Steps
* **PRR:** The updated PRR draft will be circulated for review, potentially leading to working group last call.
* **Accurate ECN:** Awaiting feedback from the AD.
* **Improving the Validation of the ACK field in packets:** The plan is to do the editorial stuff to or have the editorial cleaner to do some editorial cleanup by the next IETF and then go to working group line call.
* **TCP Act Request:** Update the document to add some pacing considerations.
* **New Socket Option:** Hold side meeting on Thursday.