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

James Bensley <> Mon, 28 June 2021 08:17 UTC

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From: James Bensley <>
Date: Mon, 28 Jun 2021 10:17:12 +0200
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To: Bob Briscoe <>,, intarea IETF list <>
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Subject: Re: [Pals] [Int-area] L2TP sequencing: Commonly disabled for IP data? Or always?
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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.