Re: [Pals] [Int-area] L2TP sequencing: Commonly disabled for IP data? Or always?

Derek Fawcus <dfawcus+lists-int-area@employees.org> Mon, 28 June 2021 18:46 UTC

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Date: Mon, 28 Jun 2021 19:46:13 +0100
From: Derek Fawcus <dfawcus+lists-int-area@employees.org>
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Subject: Re: [Pals] [Int-area] L2TP sequencing: Commonly disabled for IP data? Or always?
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On Mon, Jun 28, 2021 at 09:39:34AM +0100, Bob Briscoe wrote:
> 
> My attempt to generalize this UK-specific knowledge: No-one is going to 
> add sequencing without a reason, and the only possible reason mentioned 
> so far would be stateful compression, which these days would just slow 
> things down more than the bandwidth saved.

I also mentioned PWE fragmentation - rfc4623 - it depends upon the sequence
numbers as a fragment identifier.  So depending upon how it is implemented,
it may implicitly turn on sequencing, without the user knowing.

So the related question then becomes, where is that fragmentation support
being used - if anywhere?

DF