Comment Re:Can't we use AES? (Score 1) 139
To quote Ron Rivest, it's easy to make a secure hash function, it's hard to make a secure hash function that is also fast.
You can trivially wrap AES to make a secure hash function, but it would have a 128-bit output, which is not wide enough. It would also be slow. The trick is to make a wide hash function that runs fast.