On Thursday 30 October 2003 12:49 pm, Toad wrote: > I think Tom's idea was to make the creator of a URL do the expensive > calculation, perhaps while waiting for the insert to work. Hence: > CHK@<hashcash/routing key>,<hash of encrypted content>,<decrypt key> > Where <routing key> is derived from <hash of encrypted content> by some > operation, say a large number of operations of a secure hash. > > This could be a nice idea, the only problem is extending it to SSKs: > SSK@<pubkey hash>,<encryption entropy>,<hashcash>/<filename> > Where <routing key> is derived from the others, and applies to the > manifest file. The problem here is that the routing key cannot be > derived from the filename, as we want the filename to vary within the > SSK 'directory' - even if we use mapfiles, DBRs require > SSK@<FIXED>/<changing string> > > One possibility would be for the hashcash to be derived once only for > the SSK - but then we lose any security this gains us against flooders. > I don't think that hashcash in the URL is compatible with subspace keys, > sorry Tom.
Why not? For CHK: [EMAIL PROTECTED],<hash>,<decrypt key> where <Decrypt key> decrypts and H(hash) routes and H(hash+XXX) verifies. All you have to send is hash and XXX. For SSK: [EMAIL PROTECTED],<key>,<name> where <key> decrypts and H(H(key+name)) routes and H(H(key+name)+XXX) verifies. All you have to send is H(key+name) and XXX. Why wouldn't this work? > A further problem is that you need to be able to increase the required > amount of hashcash over time, as machines become able to do more > hashcash - this is NOT good for URLs! Well at least it would not affect routing. If at first we allocate 3 characters to XXX then that means we can make them do 2^18 hashes. If that is not enough goto 10 that's 2^60 hashes. Even if the average computer doubles in speed every 18 months we should only need to add one character to the URI every 9 years. _______________________________________________ Devl mailing list [EMAIL PROTECTED] http://dodo.freenetproject.org/cgi-bin/mailman/listinfo/devl
