[tsvwg] Naive question about L4S

Brian E Carpenter <brian.e.carpenter@gmail.com> Fri, 26 July 2019 18:09 UTC

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To: tsvwg@ietf.org
From: Brian E Carpenter <brian.e.carpenter@gmail.com>
Organization: University of Auckland
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Date: Sat, 27 Jul 2019 06:08:55 +1200
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Subject: [tsvwg] Naive question about L4S
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Hi,

draft-ietf-tsvwg-l4s-arch says:

>    Therefore, the goal is an Internet service with ultra-Low queueing
>    Latency, ultra-Low Loss and Scalable throughput (L4S) - for _all_
>    traffic.  A service for all traffic will need none of the
>    configuration or management baggage (traffic policing, traffic
>    contracts) associated with favouring some packets over others.  This
>    document describes the L4S architecture for achieving that goal.

That, and some other comments in teh draft, suggests that L4S proponents don't see any
value in conventional diffserv.

In that case, could the ECT(1) signal be replaced by a pair of DS codepoints (technically a PHB Group in RFC 2474 terminology)? Yes, they'd need to be treated as end2end signals, which would be slightly heretical in RFC2474 terms, but I'm sure we could get round that.

Regards
   Brian Carpenter