Re: [tsvwg] path forward on L4S issue #16

Jonathan Morton <chromatix99@gmail.com> Thu, 18 June 2020 08:07 UTC

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From: Jonathan Morton <chromatix99@gmail.com>
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Date: Thu, 18 Jun 2020 11:07:39 +0300
Cc: Paul Vixie <paul@redbarn.org>, TSVWG <tsvwg@ietf.org>, Ingemar Johansson S <ingemar.s.johansson=40ericsson.com@dmarc.ietf.org>
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To: Sebastian Moeller <moeller0@gmx.de>
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Subject: Re: [tsvwg] path forward on L4S issue #16
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> On 18 Jun, 2020, at 10:38 am, Sebastian Moeller <moeller0@gmx.de> wrote:
> 
> …the idea that a single hop is typically responsible for all delay variation seems like too strong a claim to me…

It's quite easy to construct a counterexample, too: any network path including two wifi hops.  Wifi is inherently a significant source of delay variation due to its shared-medium, half-duplex, CSMA/CA with ARQ architecture.  So even if the rest of that network path introduces no delay variation at all, there are still two hops independently introducing delay variations.

 - Jonathan Morton