Re: [freehaven-dev] Resource management for Chord

[Roger Dingledine <arma@mit.edu>]

On Wed, Jul 11, 2001 at 12:07:12AM -0400, Roger Dingledine wrote:
> Nodes can limit even more the distance that coins can travel by
> including policies with each coin. For example, a policy on A's coin
> to B might encourage the advogato capacity limits by declaring "You
> can give at most 15 coins from this batch to C" -- A will honor the
> first 15 coins that come in with an audit trail starting "A -> B -> C",
> and then get increasingly unhappy at B as more such coins come in. More

Actually, due to the pseudospoofing problem, this particular policy would
not work -- B could simply make up a dummy node D, trade the coin to D,
and then trade it to C. Alternatively, if B and C were conspiring more,
C could make the dummy node D and never let the coin actually touch C.

> general policies might be "You can give away at most 15 coins from this
> batch", or "Audit trails from this batch can be at most 5 hops." Policies

But these should still work.

> "Why use Chord at all, if we have this reputation system?"
> Chord provides an efficient lookup system which is crucial for finding
> the location of data. A trading system, or even a good reputation system,
> is no good without a way of efficiently doing things.
 
I should stress, since Chord has some clear security problems, that
the reputation capital trading system we describe is almost entirely
independent of the back-end storing mechanism. So if somebody fixed
Chord, we'd just use the fixed one; and if we needed a more secure but
less efficient back-end, then we could easily switch to it.

--Roger