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

Paul Vixie <paul@redbarn.org> Wed, 17 June 2020 20:50 UTC

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From: Paul Vixie <paul@redbarn.org>
To: "Black, David" <David.Black@dell.com>, tsvwg@ietf.org
Cc: Ingemar Johansson S <ingemar.s.johansson=40ericsson.com@dmarc.ietf.org>, "tsvwg@ietf.org" <tsvwg@ietf.org>, Sebastian Moeller <moeller0@gmx.de>
Date: Wed, 17 Jun 2020 20:50:27 +0000
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Subject: Re: [tsvwg] path forward on L4S issue #16
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On Wednesday, 17 June 2020 18:19:23 UTC Sebastian Moeller wrote:
> > ...
> 
> 	[SM] ... my hypothesis that L4S was really only
> ever intended, designed, and tested for a single use-case, short RTT, low
> hop-count downlink paths from content/CDNs to consumers. ...

that's not really a hypothesis, but rather an observation. by the time a 
packet has traversed a metropolitan area, the scale of its transit time will 
be greater than the difference in scales between the dual queues of dualq.

to those who were confused when i referred to L4S as a datacenter protocol, 
this is why: getting into the microsecond vs. millisecond queue in an edge 
switch or router at the far-end campus or home or LAN won't change the lived 
experience of your application or user in any way since the packet is already 
a half dozen or more milliseconds from where it was born.

-- 
Paul