md5 with small strings

From: Gary Robinson (grobinson_at_transpose.com)
Date: 07/28/03 

Date: 28 Jul 2003 12:35:22 -0700

Hello,

For an application we're developing we're thinking of using md5 as a
16-byte hash for strings that could by anywhere from 20 to 200 bytes
long. There could be on the order of one million of them to be hashed.

I understand that md5 is very good at avoiding collisions, but what
about in cases where the strings are that short? Are the odds good
that we'll have no collisions (a handful of collisions wouldn't be the
end of the world for this application, but it would make more sense to
use this hash if the odds are good that there wouldn't be any.

Many thanks in advance for any help,

Gary

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