Re: [tsvwg] SCE / L4S and fragmentation

Jonathan Morton <> Sun, 15 March 2020 23:36 UTC

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From: Jonathan Morton <>
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Date: Mon, 16 Mar 2020 01:35:54 +0200
Cc: "" <>, "Black, David" <>
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To: Bob Briscoe <>
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Subject: Re: [tsvwg] SCE / L4S and fragmentation
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Isolating one key point:

> On 15 Mar, 2020, at 8:14 pm, Bob Briscoe <> wrote:
> I (and David Black) have argued that a separate draft is needed to update fragment reassembly in RFC3168. Can you please accept that we are not going to update ECN fragmentation and reassembly in rfc6040update-shim. Then it can unblock and be published.
> rfc6040update-shim is meant to be about encap and decap. It would allow this draft to become unstuck if it just said fragmentation and re-assembly is out of scope (which it is). 

I have said several times in the past few days that I agree with that approach, and I'm sure David Black is well aware of that.

However, the -10 revision (which appears to be current) still contains the section and some language covering fragmentation and reassembly.  To be consistent with this approach, you need to update it to simply refer to RFC-3168 for the relevant semantics.  Then I think it will be possible to make progress.

We can discuss separately what, if anything, should be done to RFC-3168 on this topic.

 - Jonathan Morton