> > If you are really paranoid and don't want any collisions in the next > > 10 years: don't let strangers in your venti. > > Which, to close the circle, as Tim points out, you are always doing, > each time you receive an email :-)
not all email is from strangers. in mbox format, messages are concatinated. for a block size of b, the size of the existing mailbox is 0 ... b-1 mod b. therefore, there is a 1/b chance of the attack succeeding, even if the attacker knows the block size and pads to the next block. i suppose that this is a fair assumption, since we're given that the attacker is attacking venti. this is esentially the same reason that mbox format will eat alot of storage, even if you're using venti. - erik
