[Bloat] incremental deployment, transport and L4S (Re: when does the CoDel part of fq_codel help in the real world?)

[Mikael Abrahamsson]

On Wed, 28 Nov 2018, Dave Taht wrote:

> see ecn-sane. Please try to write a position paper as to where and why
> ecn is good and bad.
>
> if one day we could merely establish a talmud of commentary
> around this religion it would help.

>From my viewpoint it seems to be all about incremental deployment. We have 
30 years of "crud" that things need to work with, and the worst-case needs 
to be a disaster for anything that wants to deploy.

This is one thing about L4S, ETC(1) is the last "codepoint" in the header 
not used, that can statelessly identify something. If anyone sees a better 
way to use it compared to "let's put it in a separate queue and CE-mark it 
agressively at very low queue depths and also do not care about 
re-ordering so a ARQ L2 can re-order all it wants", then they need to 
speak up, soon.

I actually think the "let's not care about re-ordering" would be a 
brilliant thing, it'd help quite a lot of packet network types become less 
costly and more efficient, while at the same time not doing blocking of 
subsequent packets just because some earlier packet needed to be 
retransmitted. Brilliant for QUIC for instance, that already handles this 
(at least per-stream).

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se