Re: [tsvwg] L4S drafts: Next Steps

Jonathan Morton <> Sat, 20 March 2021 14:48 UTC

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From: Jonathan Morton <>
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Date: Sat, 20 Mar 2021 16:48:09 +0200
Cc: Sebastian Moeller <>, Bob Briscoe <>, "" <>
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To: "Livingood, Jason" <>
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Subject: Re: [tsvwg] L4S drafts: Next Steps
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> On 20 Mar, 2021, at 4:33 pm, Livingood, Jason <> wrote:
>> i believe nobody is asking for rocks (nor shrubberies) here, this is really about a convincing demonstration that the whole L4S design, consisting of network and protocol bits actually behaves like a coherent design and not two disjoint sub-projects that will never really harmonize?
> Maybe I am being too simplistic with my operator mindset, but I'd prefer that any long-term decision be data-driven. And to collect significant data you need to conduct an experiment. Which in turn seems to potentially depend on an experimental RFC. So if we want the convincing demonstration sought & real data to drive a long-term decision then how is an experimental RFC not the logical next step?

Field studies would require the published RFC.  Lab studies can already be performed (and to some extent have been).  The lab studies have shown, far from a promising system that might be ready for a field trial, one that shows worrying failure modes that primarily affect innocent bystanders.  These effects, moreover, were fairly predictable by theory (in that I did, in fact, predict them before the lab study results were available).

What we're asking for is a system that at least behaves reasonably under lab conditions, chosen to represent realistic challenge scenarios likely to occur in the real world.  Only then can we have any confidence that L4S will not cause problems anywhere and everywhere that it is deployed.

 - Jonathan Morton