wrote on Jun 3^rd, 2003 at 4:59am:

Fair enough.  Yes, cracking 128 bit encryption requires far more computing power than 64 bit, and if I were going to use a public-private key encryption system, I would certainly choose the highest number of bits possible, but the main point is that if someone develops an efficient factorization algorithm (say O(lg n) where n is the number being factored) then the number of bits used is irrelevant.

I have to agree with Marty, Anonymous -- RSA hasn't been "cracked", just brute-forced.  What you're describing above (the discovery of an efficient factoring algorithm) would be a true "crack".  It would also represent quite an advance in mathematics, considering that the factoring problem has been around for a couple of millenia or more.

Of course, El Gamal encryption (which PGP can also use) relies upon discrete logarithms, rather than factoring, so that's another problem entirely. :)

Nice overview, BTW.

Skeptic