On Mon, Dec 17, 2001 at 06:48:55PM -0500, Scott Young wrote: > On Monday 17 December 2001 05:13 pm, you wrote: > > Another question to bore you guys ;) > > > > I understand a message with ahops-to-live value of 1 is sometimes still > > forwarded on, to reduce the information an attacker could get out of it. > > What I don't understand, is what information could be learned from the > > fact thatsomeone will be the last node reached on the path. > > > > For example, why would I want to know that some node at the end of the > > path replies with a Reply.NotFound message? What kind of discriminating > > information could I get from that? > > It is for malicious ADJACENT nodes. If node A has a direct connection to > node B, node A can find out if the data exists on that node by requesting the > file with a htl of 1. This knowlege can be bad, as Sebastian pointed out. > With the certain probibility of forwarding HTL 1 requests, the act of > requesting the data can put the data on the node. This has the benefit of > mirroring the data and improving legal arguments. > Additionally, site insertors tend to use a fixed HTL; randomly not reducing the HTL provides substantial extra anonymity for them. > Actually, why isn't the HTL concept abonded and replaced with a high certain > probability? This way nodes can't choose a HTL that they can use for gaining > data from freenet. Here is a table of probabilities and and average hops: > > 50% 1 hop > 70% 1.9 hops > 80% 3.1 hops > 90% 6.6 hops > 95% 13.5 hops > 96% 17.0 hops > 97% 22.8 hops > 98% 34.3 hops > 99% 68.0 hops > > And if you want to know how I got theese values, here's the formula: > 1. probability^hops=0.5 (0.5=50%) > 2. log(probability^hops)=hops*log(probability)=log(0.5) > 3. hops=log(0.5)/log(probability) > > > If a node removes the request by a probabilistic chance, it could return with > two messages, one saying the probabilty finally told it to stop searching and > another to tell that it could not find a closer node. If the probability did > not fail, nodes could then continue the search with their next-closest node. > > > Scott Young > > _______________________________________________ > freenet-tech mailing list > [EMAIL PROTECTED] > http://lists.freenetproject.org/mailman/listinfo/tech
-- The road to Tycho is paved with good intentions _______________________________________________ freenet-tech mailing list [EMAIL PROTECTED] http://lists.freenetproject.org/mailman/listinfo/tech
