Re: comments on Don's "Cypher Bank"

[mark@coombs.anu.edu.au (Mark)]

richard childers (rchilder@us.oracle.com) :
>It might be more likely to arrange for a compromise where numbered accounts
>are permitted iff account balances are publically available also.
>
>This might have interesting spinoffs, such as allowing a much wider range
>of interested individuals, access to economic data at the level usually
>reserved for banking institutions. We might - as many people have noted -
>learn much and contribute accordingly to both economic and cryptographic
>theory.

It is said information should be free... however, if someone was (and someone
undoubtedly would), to monitor the bank(s) they would probably see accounts
going up and down by various amounts and it should be possible to track 
transactions between identities. This, coupled with widespread traffic
analysis (assuming no padding had occured) would allow someone to deduce that
Alice had asked something of Bob and had then paid him. This probably isnt 
particularly inviting to the majority to know that your funds could be traced
very anonymously and that patterns could be formulated... for instance three
times a month various amounts are deducted from your account and those exact
same amounts appear in an account known to be owned by a 1-900 phone sex 
number. That would have an affect on your reputation, (if not your marriage
if your True Name was known), if it was published. (The 1-900's identity
could be discovered simply by someone using the service and noting what
psuedonym took your funds, or if that was changed, noting which account
increased by your $127.30. (It was an intense call I guess :)

If you wish to entertain such a testbed financial system be very careful with
any decision made and work through each possible consequence. Most people I
think would prefer to remain anonymous. I know I would, in the long run.

Mark
mark@coombs.anu.edu.au