Copa: Practical Delay-Based Congestion Control for the Internet

on YouTube ↗24m

" summary

Algorithm sets target rate = 1/(δ · dq) and estimates dq by taking a minimum over a half-RTT window to remove positive noise, periodically emptying queues so new flows learn true RTT. Control loop makes additive-increase/additive-decrease toward that target with a velocity term, and a detector switches to AIMD on 1/δ when buffer-fillers appear. Claims: empties queues every 5 RTTs, yields Cubic-like throughput with much lower delay, fairer across RTTs, robust to non-congestive loss and large buffers.

AI-written summary · about

" chapters (12)

1. 0:00Introduction
2. 0:21Why are we still talking about it
3. 4:05Basic Goals
4. 4:25Target Rate
5. 8:24Copa Algorithm
6. 9:14One Sender Case
7. 10:56Two Consequences
8. 13:12Experimental Results
9. 14:02Limitations
10. 15:24Performance
11. 17:44Summary
12. 18:55Questions

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