Re: Non-PK encryption not vulnerable via low key length?!
Mark G. Scheuern (mgscheue@Oakland.edu)
Wed, 15 Mar 1995 22:32:38 -0500 (EST)
On Wed, 15 Mar 1995, Jonathan Cooper wrote:
> Date: Wed, 15 Mar 1995 20:35:44 -0500 (EST)
> From: Jonathan Cooper <entropy@IntNet.net>
> To: Vishy Gopalakrishnan <vishy@sph.umich.edu>
> Cc: bugtraq@fc.net
> Subject: Non-PK encryption not vulnerable via low key length?!
> You are wrong.
>
> If the key is only 128-bit, that's a much smaller keyspace to
> brute-force attack than a 1024-bit key.
>
> (do the math)
>
> -jon
Okay, let's see. 2^128 = 3.4e38. Suppose you can somehow try one
billion keys per second. Then it will take you 3.4e29 seconds or
about 1e22 years to try every possible key. A shorter length of
time than it would take with a 1024 bit key, but I don't think I'd
lose much sleep over it.
Mark
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