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MD5 versus SHA
> From: Ran Atkinson <rja@bodhi.nrl.navy.mil>
> IMNVHO, The long-run algorithm should NOT be our focus now.
> Our focus now should be on
> 1) algorithm-indendent protocol specs
> and 2) a right-now algorithm that is good enough, but not
> necessarily perfect, and has tolerable performance.
>
I somewhat agree, but it _is_ valuable to prepare for the possible next
generation, vis a vis 3DES.
> The early performance data I'm hearing about for SHA makes me VERY
> doubtful that it is practical to deploy SHA universally or to get
> it used on very many packets. We need an authentication-without-
> confidentiality mechanism that is practical to use on virtually every
> packet with acceptable performance.
Absolutely! You do remember my comments about slow embedded 186's?
> SHA does not appear to be
> that algorithm at this time with currently available commercial systems
> (e.g. 90MHz 586s, SPARCs, Alphas, etc).
>
That's disappointing. I had hoped that with the lessons learned, and
the fact that it was based on MD4, it could be _FASTER_ than MD5.
Unfortunately, the Touch report on MD5 doesn't include 68K machines,
so I can't compare MD5 and the report of SHA 4.4 MBps for 68030/25 --
which would be 32+ Mbps, much faster than the MD5 20 Mbps on the 486/33.
Anyway, I sent the SHA draft off to CNRI, and we can test MD5 against
SHA in the best way possible -- on the same machine with the same data
in the same Headers!
Could ISI put together a quick test of SHA in one of it's platforms?
Bill.Simpson@um.cc.umich.edu