[prev in list] [next in list] [prev in thread] [next in thread]
List: cypherpunks
Subject: Re: Paranoid
From: Karl Lui Barrus <klbarrus () owlnet ! rice ! edu>
Date: 1993-10-30 10:53:10
[Download RAW message or body]
-----BEGIN PGP SIGNED MESSAGE-----
I'm not exactly sure what this thread is about :-) but I do have some
numbers:
Differential cryptanalysis of DES requires 2^47 = 140737488355328 =
1.4 10^14 known plaintexts.
The complexity of a brute force DES attack (keysearch) is 2^56 =
72057594037927936 = 7.2 10^16, or 2^55 = 36028797018963968 = 3.6 10^16
if you are efficient.
Similary, brute forcing IDEA is 2^128 =
340282366920938463463374607431768211456 = 3.4 10^38
The best factoring algorithm (gopher plug: check in Misc/ for
a recent "bits and difficulty factoring post") for a 1024 bit key is
a complexity of 4.42 10^29.
Somewhere around 1600 bits comes a point where it is "easier" to
attack IDEA than factor the resulting number.
Karl Barrus
<klbarrus@owlnet.rice.edu>
-----BEGIN PGP SIGNATURE-----
Version: 2.3a
iQCVAgUBLNKNqYOA7OpLWtYzAQFlkwP+PdenJNJOKm9zcxkL4Zaq22aujfa2SAgk
1NILjQzZI8uZe9FIn8p2uEoS3YjYskg40tEMeohhGqZ371s/ndlTjDDhga0PCXLj
Q4UHoowTVR9hx/cVGzLhuZbyAwbbqAvygGQNKN1iXn3IqpLoNV3Do+TtUj0xLt1l
0j1gl055YL4=
=Vl2r
-----END PGP SIGNATURE-----
[prev in list] [next in list] [prev in thread] [next in thread]
Configure |
About |
News |
Add a list |
Sponsored by KoreLogic