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Re: [Cfrg] new authenticated encryption draft

"Hal Finney" <hal.finney@gmail.com> Tue, 29 August 2006 16:51 UTC

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Date: Tue, 29 Aug 2006 09:51:40 -0700
From: Hal Finney <hal.finney@gmail.com>
To: "David A. McGrew" <david.a.mcgrew@mindspring.com>
Subject: Re: [Cfrg] new authenticated encryption draft
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One sentence that struck me as kind of odd was this, in section 2.1:
"The strength of the authentication of P, IV and A is attenuated by
the length t of the authentication tag."

Attenuation means a weakening or reduction, so this makes it sound
like a longer tag will result in diminished security. Maybe you could
substitute "controlled by" or "determined by", or even "exponential in
the length t". A good algorithm ought to be exponential in t, I'd
think, othewise it is being wasteful.

Hal Finney

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