Re: Parameters for Diffie-Hellman-Merkle

From: Paul Crowley (paul_at_JUNKCATCHER.ciphergoth.org)
Date: 06/09/03 

Date: Mon, 09 Jun 2003 17:25:06 GMT

ggr@qualcomm.com (Gregory G Rose) writes:

> this is one case where size doesn't matter. As for finding one,
> choose a random element "a" (may as well start with 2), and
> calculate g = a^((P-1)/Q) mod P. If g != 1 then it's a generator of
> the order Q subgroup. If it is, try again with a different a.

Of course the chances that you'll fail first time around are 1/Q, so
implementing the check for g != 1 is probably a waste of time...

> Well, you know what a group is, right? CAIN and ABEL: Closure,
> Associative, Identity, iNverse, and Abelian (Commutative).

Just to clarify: groups don't need to be commutative, Abelian groups
do. 

-- 
  __  Paul Crowley
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