[Cake] Advantages to tightly tuning latency

[Jonathan Morton]

> On 22 Apr, 2020, at 1:50 am, Dave Taht <dave.taht at gmail.com> wrote:
> 
> Jon, how's SCE looking? ready for a backport yet?

We can't do any sort of wide deployment of SCE until it's been approved as an Internet experiment by the IETF.  Interested individuals can already compile the SCE-enabled kernel and jump through the hoops to try things out - carefully.  There's a bit of infrastructure code to go with the new TCP algorithms and qdiscs, so I'm not certain how easy a backport would be; better to just build the (relatively) current code for now.

IETF TSVWG interim meeting next week (the second of two replacing planned in-person sessions at Vancouver) will discuss the big ECT(1) issue, which is hotly disputed between SCE and L4S.  The key question is whether ECT(1) should become a classifier input to the network (orthogonal to Diffserv but with some of the same basic problems), or an additional congestion signal output from the network (indicating a lesser degree of congestion, to which a smaller and more nuanced response is desired).  It's anyone's guess how that will turn out, but the technical merit is on our side and that really should count for something.

If you're keeping an eye on the TSVWG list, expect a major bombshell to drop there in the next few days.

 - Jonathan Morton