BBR, the new kid on the TCP block

(blog.apnic.net)

360 points pjf | 2 comments | 09 May 17 08:56 UTC | HN request time: 0.895s | source

Show context

huhtenberg ◴[09 May 17 09:18 UTC] No.14298640[source]▶

>>14298576 (OP) #

Any data on BBR vs Reno and Vegas sharing?

Link capacity estimation is easy. It's the co-existing gracefully with all other flow control options that's tricky.

replies(2): >>14298688 #>>14298812 #

1. throwaway2048 ◴[09 May 17 09:33 UTC] No.14298688[source]▶

>>14298640 #

There is also no mention of how it handles things like wireless links with high jitter and intermittant not related to flow rate packet loss.

replies(1): >>14298765 #

2. tankenmate ◴[09 May 17 09:56 UTC] No.14298765[source]▶

>>14298688 (TP) #

Well it does mention that BBR uses "The RTT is the minimum of all RTT measurements over some time window that is described as “tens of seconds to minutes”." This is a much larger measuring window than previous RTT tracking TCP. At 10s of seconds it is also hopefully enough to tackle the most common forms of jitter and intermittent flows.

At truly bad flow characteristics you need to start some truly weird line coding methods with stream data split over multiple packets with redundant coding to rebuild dropped packets etc, but this kind of thing just kills latency.

↑