Hi, and some comments

Michael J Freedman mfreed@MIT.EDU
Tue, 27 Feb 2001 23:04:10 -0500


At 09:47 PM 2/27/2001 -0600, you wrote:
>For Freenet, however, where the goal is anonymity, accounting is exactly
>what we don't want. I would, however, be interested in hearing about any
>sort of system of symbolic reciprocity balancing (micropayments) which is
>totally decentralized. Ever system that I'm aware of uses a central trust
>authority (bank), which is the main reason that I consider micropayments
>to be unsuitable for Freenet. Obviously some system of abuse management is
>needed, but it has to be fully decentralized for our particular needs.

The requirement for some centralized bank is only necessary when you are
describing some fungible micropayment scheme -- that is, payments are
redeemable for other services in your system.  If your concern is largely
to prevent abuses -- e.g., congestion management for temporary resources --
you can use non-fungible type schemes, such as proofs of work (PoW).  Adam
Back's hash cash is a clear example of such.

These don't require any centralized bank server...coins are "minted"
recipient-specific.  (I think Wei Dei's B-money protocol also describes a
decentralized system, although of a pseudo-reputation-based nature.)

We describe this whole issue of accountability with (pseudo) anonymity in
the O'Reilly P2P book.  You can find a copy of our accountability chapter at:

http://freehaven.net/papers.html

Currently, we're rethinking the FreeHaven design.  One of our plans is to
develop a free, low-latency, two-way mix-net for an anonymizing layer.  We
hope to be able to use such as a pluggable research tool to study
micropayment, reputation, and other congestion management (abuse
prevention) techniques.

Thanks!
--mike




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"Not all those who wander are lost."                  mfreed@mit.edu