[2502] in cryptography@c2.net mail archive
Re: TIME Magazine on GSM cell phone crack
daemon@ATHENA.MIT.EDU (Andreas Bogk)
Tue Apr 14 12:16:48 1998
To: Bill Frantz <frantz@netcom.com>
Cc: marc@cryptsoft.com, Steve Bellovin <smb@research.att.com>,
Marc Horowitz <marc@cygnus.com>, Declan McCullagh <declan@well.com>,
cryptography@c2.net
From: Andreas Bogk <andreas@artcom.de>
Date: 14 Apr 1998 17:09:40 +0200
In-Reply-To: Bill Frantz's message of "Mon, 13 Apr 1998 21:51:49 -0800"
Bill Frantz <frantz@netcom.com> writes:
> My question is how many challenge/response pairs are needed to pare the
> keysize down enough to make brute force a reasonable attack?
You get the key bits in chunks of 16 bits each, and you need about
20000 challenge/response pairs for each chunk.
Andreas
--
The obvious mathematical breakthrough [to break modern encryption]
would be development of an easy way to factor large prime numbers.
-- Bill Gates from "The Road Ahead," p. 265.
