[RC5] Re: Solutions for a faster DES-II-3

Jocelyn Doire jdoire at cslo.consultronics.on.ca
Fri Jul 31 20:00:27 EDT 1998

> I like the idea of prefetching the blocks. However, individual 
> fetches of the ciphertext are going to have the same problem that
> fetching blocks has.

Me too I like the idea... :)  Fetching only the ciphertext instead of
N blocks make the problem 1/N smaller. Furthermore, there is less
data to send, making the problem even smaller.  As I said in a
previous reply, a little random spread of the starting time should
make the problem fairly manageable.

> Instead, have the proxy network multicast the ciphertext to all IP
> addresses that requested prefetch blocks.

I can see many problems with that suggestion: 1) not all clients are
on-line all the time. 2) you have to go through firewall. 3) you
open a door for spamming the clients 4) not everyone will be
comfortable of having the servers sending messages to the client,
for security reasons among other things.

> Also, since there is no reason to allow off-line clients on DES-II
> contests any more, hardwire the DES buffer sizes to 1:1.

I don't agree. Most probably we will need most of the 14 hours to
find the key, so if off-line clients connect near the start and then
let's say 10 hours later, the info probably will still be relevant.

To unsubscribe, send 'unsubscribe rc5' to majordomo at lists.distributed.net
rc5-digest subscribers replace rc5 with rc5-digest

More information about the rc5 mailing list