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Re: AH and ESP Orthogonality
> From: smb@research.att.com
> We therefore have a situation where ESP must be used in conjunction with
> AH, and no document saying so.
Hmmm, perhaps I am mistaken, but as I have already quoted the "documents
saying so" in a previous message, do I need to quote them again?
Why do you think that the documents don't say so? Is there a suggestion
you could make to improve the text?
> Worse yet, we're paying the overhead
> price for a new header twice.
>
True. That was the tradeoff for orthogonality. It was 8 bytes for AH.
But, if we also require AH for message origin authentication, while ESP
provides integrity, we haven't saved anything. As noted by Bob Baldwin
last week, we have a bigger hit for processing costs, too.
So, which do you prefer? 33% slower processing???
Look folks, we discussed this all last year. We knew about the cut and
paste attack before we wrote the documents. We referenced the Bellovin
presentation in the documents.
The "mistake" that Atkinson made MUST be something else that we didn't
already know about.
WSimpson@UMich.edu
Key fingerprint = 17 40 5E 67 15 6F 31 26 DD 0D B9 9B 6A 15 2C 32
BSimpson@MorningStar.com
Key fingerprint = 2E 07 23 03 C5 62 70 D3 59 B1 4F 5E 1D C2 C1 A2
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