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bio website randombit.net
location Vermont
age 33
visits member for 3 years, 4 months
seen Jul 15 at 14:16

Hobo in training


Jul
21
comment Should DES be avoided when developing new systems?
It might be worth distinguishing between CBC and CTR in terms of the problems that are encountered with an n bit cipher. As I understand it, after 2**(n/2) CBC blocks, one can expect to start extracting information about the plaintext, whereas with CTR the only change is that you can distinguish the keystream from a uniform random string, because you would expect to see a collision after 2**(n/2) blocks, but wouldn't with CTR. Obviously the best solution regardless is to use a cipher with a larger block, but I do think these are very different failure modes.
Jul
21
revised Should DES be avoided when developing new systems?
Expand a bit, link to time memory tradeoff paper
Jul
14
answered Is key size the only barrier to the adoption of the McEliece cryptosystem, or is it considered broken/potentially vulnerable?
Jul
14
answered Taking advantage of one-time pad key reuse?
Jul
14
awarded  Scholar
Jul
14
accepted Known methods for constant time (table-free) AES implementation using 'standard' operations?
Jul
13
comment Replacing the Rijndael S-Box?
I assume your question has an implicit "holding other cryptographic properties constant", since an sbox of [1,2,...,255,0] has cycle type 256, but would make a fairly poor sbox. You may want to make this explicit.
Jul
13
revised Is it feasible to build a stream cipher from a cryptographic hash function?
Describe how to break the system presented
Jul
13
awarded  Mortarboard
Jul
13
awarded  Editor
Jul
13
revised Known methods for constant time (table-free) AES implementation using 'standard' operations?
Fix spelling in question title
Jul
13
awarded  Critic
Jul
13
answered Should DES be avoided when developing new systems?
Jul
13
awarded  Nice Answer
Jul
12
awarded  Student
Jul
12
asked Known methods for constant time (table-free) AES implementation using 'standard' operations?
Jul
12
awarded  Teacher
Jul
12
answered With sufficient randomness, is XOR an acceptable mechanism for encrypting?
Jul
12
answered Is it feasible to build a stream cipher from a cryptographic hash function?
Jul
12
awarded  Precognitive