Subject: [tsvwg] Takeaways for HPCC++

From: "Rui, Miao" <[email-masked]>
Date: Mon, 03 Aug 2020 02:21:09 +0800

Hello TSVWG members,

It was our pleasure to present HPCC++ in the IETF-108 meeting this week. We appreciate your valuable feedback. Our current draft is located at https://tools.ietf.org/html/draft-pan-tsvwg-hpccplus-01.
Here, we have summarized a list of takeaways to further improve the draft. 

1. HPCC++ is a generic congestion control scheme that works for high-speed networks. It requires to have window limit and ACK self-clocking, which is out of the definition of RoCEv2 but should instead work well for TCP/iWRAP. In addition, HPCC++ conforms to the paradigm of existing TCP congestion control, such as switch marking, receiver feedback, and sender enforcement. The major changes are using inband telemetry as the congestion feedback and it is incremental. In the next revision, we describe clearly how it works for TCP/UDP and related protocols.

2. HPCC++ works for both data centers and the Internet. We will add descriptions and results for the Internet-scale size and latency in the next revision.

Thanks again for the comments. Please feel free to let us know if you have more thoughts.

All the best,
Rui, Rong, Barak