
Intro to Congestion Control - luu
http://squidarth.com/rc/programming/networking/2018/07/18/intro-congestion.html
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kev009
I deployed a custom implementation of IETF BBR on FreeBSD at one of the major
CDNs, Limelight, that was wildly successful for the company. One bit of wisdom
I will share after having worked in this space for a few years, depending on
what you're optimizing for, it's pretty easy to out-muscle the competition and
make a "better" CC for your own selfish purposes at a small or large scale.

The real challenge in this space is balancing flow fairness, link utilization,
buffering delay, heuristics or models to differentiate congestion from
unrelated signals like RF interference causing channel loss, and making the
whole thing computationally inexpensive. It's further difficult because the
internet is a free for all, in a closed network flow control between each hop
would make congestion control unnecessary as you could use a congestion
avoidance algorithm instead. Fibre channel is an example of that in wide use
with its credit based flows.

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saminiir
I've been meaning to do a similar blog post for my hobbyist TCP stack, but
this here does explain it more concisely than I could.

