Lucrative update

2003-02-18 Thread R. A. Hettinga
--- begin forwarded text Status: RO From: Patrick [EMAIL PROTECTED] To: 'Digital Bearer Settlement List' [EMAIL PROTECTED] Subject: Lucrative update Date: Tue, 18 Feb 2003 13:05:40 -0600 Sender: [EMAIL PROTECTED] Lucrative release 4 is out. I know many people are used to seeing releases

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread Arnold G. Reinhold
At 1:09 PM +1100 2/18/03, Greg Rose wrote: At 02:06 PM 2/17/2003 +0100, Ralf-Philipp Weinmann wrote: For each AES-128 plaintext/ciphertext (c,p) pair there exists exactly one key k such that c=AES-128-Encrypt(p, k). I'd be very surprised if this were true, and if it was, it might have bad

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread Matt Crawford
... We can ask what is the probability of a collision between f and g, i.e. that there exists some value, x, in S such that f(x) = g(x)? But then you didn't answer your own question. You gave the expected number of collisions, but not the probability that at least one exists. That

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread Arnold G. Reinhold
At 5:45 PM -0600 2/18/03, Matt Crawford wrote: ... We can ask what is the probability of a collision between f and g, i.e. that there exists some value, x, in S such that f(x) = g(x)? But then you didn't answer your own question. You gave the expected number of collisions, but not the

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread David Wagner
Matt Crawford wrote: But here's the more interesting question. If S = Z/2^128 and F is the set of all bijections S-S, what is the probability that a set G of 2^128 randomly chosen members of F contains no two functions f1, f2 such that there exists x in S such that f1(x) = f2(x)? Vanishingly

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread Sidney Markowitz
Ed Gerck [EMAIL PROTECTED] wrote: For each AES-128 plaintext/ciphertext (c,p) pair with length equal to or larger than the unicity distance, there exists exactly one key k such that c=AES-128-Encrypt(p, k). Excuse my naivete in the math for this, but is it relevant that the unicity distance

Re: AES-128 keys unique for fixed plaintext/ciphertext pair?

2003-02-18 Thread Ed Gerck
The relevant aspect is that the plaintext and key statistics are the determining factors as to whether the assertion is correct or not. In your case, for example, with random keys and ASCII text in English, one expects that a 128-bit ciphertext segment would NOT satisfy the requirement for a