On Wed, Feb 17, 2010 at 3:34 PM, Salman Abdul Baset <[email protected]> wrote: > DHTs, however, use a hash function to map resources to nodes, so node-ID > length and hash function output length becomes an issue. The confusion lies > in the ability to use a hash function that emits a greater than 128-bit > value, and then mapping it to the 128-bit node-ID by dropping the most > significant bits. The argument is that by dropping the MSBs, we likely loose > the randomness guarantees which are necessary from the load balancing > perspective. Thus, we are restricted to using a 128-bit hash function for > all DHTs (Kademlia, Pastry, CAN etc). Restricting the use of hash functions > for all DHTs is not necessarily ideal from the viewpoint of future proofing.
Huh? Any reasonable hash function is just as random in the low-order bits (what you get if you drop the MSBs) as in the high order bits. This is certainly a necessary condition for any cryptographic hash function to deliver the full security of its output length. -Ekr _______________________________________________ P2PSIP mailing list [email protected] https://www.ietf.org/mailman/listinfo/p2psip
