Re: Comments on draft-ietf-bfd-secure-sequence-numbers-12.txt

Alan DeKok <> Tue, 16 January 2024 23:48 UTC

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Subject: Re: Comments on draft-ietf-bfd-secure-sequence-numbers-12.txt
From: Alan DeKok <>
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Date: Tue, 16 Jan 2024 18:47:54 -0500
Cc: rtg-bfd WG <>,
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To: Jeffrey Haas <>
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On Jan 16, 2024, at 12:00 PM, Jeffrey Haas <> wrote:
> This means the two scenarios we have during the first transition to ISAAC in the face of packet loss are:
> 1. It's on "this" page.
> 2. It's on the prior page.

  The simple solution to page issues is to just require that there be no more than 255 lost packets allowed.  That way the current packet is always in the first page of derived ISAAC values.

> That said, deployed Detect Mult values tend to be low, and often simply default to 3.

  Exactly.  I'll add a note to this effect.

> So, please review the next round of text vs. optimizing bfd.

  I'll do that next.

  For now, I've largely reworked the text.  The new text is at:

  The reworked text doesn't address all of your review, but it does go into great detail into how to initialize and operate meticulous keyed ISAAC.  If defines a large number of variables specific to this Auth Type method.  That may seem surprising, but I think that the resulting text was made clearer.

  The document still needs updates to address the other comments in your review, but it's late here, and the bulk of the work seems to be done.  I'll do more tomorrow, in order to get this off of my plate.

  Alan DeKok.