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

Bob Briscoe <> Mon, 28 June 2021 08:39 UTC

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To: James Bensley <>,, intarea IETF list <>
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From: Bob Briscoe <>
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Date: Mon, 28 Jun 2021 09:39:34 +0100
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Subject: Re: [Pals] [Int-area] L2TP sequencing: Commonly disabled for IP data? Or always?
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On 28/06/2021 09:17, James Bensley wrote:
> On Sun, 27 Jun 2021 at 23:22, Bob Briscoe <> wrote:
>> James,
>> [First apologies to everyone for asking the question then not following
>> up on the answers until now - I went off line for a while.]
>> See inline tagged [BB]...
>>> [JB] In that case  - sequencing isn't used for BT Wholesale services.
>> [BB] Thank you. It sounds like you have some reason for your certainty
>> here. Can you elaborate on what makes you so certain sequencing isn't used?
> Hi Bob,
> Sure, my current employer is a BTW customer and I have checked our
> live/current set-up and L2TP sequencing is disabled. I also worked for
>   different UK operator previously that was also a BTW customer. I've
> checked the old configs and outputs from when I was there, and again
> L2TP sequencing was disabled (I'm in close contact with those former
> colleagues they confirm it is still disabled). I've asked a few
> friends at other UK operators, and none of them have L2TP sequencing
> enabled on their BTW tunnels. I've also scanned the BTW docs and can't
> find anything that mentions it is supported.

[BB] Thx for looking into this in such depth.

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.



> Cheers,
> James.

Bob Briscoe