Matthew Toseland wrote:
> If you route randomly on each hop I'd 
> expect to on average not get very far, because *most links are short links* 
> on a small-world network.

Yup, it's counter-intuitive because of clustering but small world
networks do have fast mixing times, ie short random walks will quickly
take you out of your local neighbourhood.

> On the other hand if you choose a random location 
> and consistently route towards it you should have an equal chance of ending 
> up anywhere on the network.

Almost equal - the probability of ending up at a node is proportional to
the amount of keyspace it controls, which is somewhat unevenly
distributed even in an ideal network.

> The catch is that if you route lots of requests 
> to different random locations, and the attacker can connect the requests, he 
> can gradually narrow down the locations you could have started in.

True, and Borisov doesn't address this problem (which IMO is a major
one). As you know, my proposed solution is to reuse the same random path
for as long as possible (tunnels).

> On a cell of 10,000 nodes, if on 
> average each node goes down once a day, and this impacts on 10 other nodes, 
> we have ~ 100,000 messages ... perhaps hundreds of megabytes, so it may be 
> that cells this big are feasible.

There's a tradeoff here: large cells provide a large anonymity set if
the attacker's outside the cell, but they make it more likely that
there's an attacker inside the cell who can attack key distribution etc.

Cheers,
Michael

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