Re: CRC was: Re: [HACKERS] beta testing version

[Bruce Guenter]

On Thu, Dec 07, 2000 at 04:01:23PM -0800, Nathan Myers wrote:
> 1. Computing a CRC-64 takes only about twice as long as a CRC-32, for
>    2^32 times the confidence.  That's pretty cheap confidence.

Incidentally, I benchmarked the previously mentioned 64-bit fingerprint,
the standard 32-bit CRC, MD5 and SHA, and the fastest algorithm on my
Celeron and on a PIII was MD5.  The 64-bit fingerprint was only a hair
slower, the CRC was (quite surprisingly) about 40% slower, and the
implementation of SHA that I had available was a real dog.  Taking an
arbitrary 32 bits of a MD5 would likely be less collision prone than
using a 32-bit CRC, and it appears faster as well.
-- 
Bruce Guenter <[EMAIL PROTECTED]>                       http://em.ca/~bruceg/

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