Re: Anonymity: A Modest Proposal

[Adam Shostack <adam@lighthouse.homeport.org>]

Lance Cottrell wrote:

| How open is the protocol? Is there and API for it? Does anyone know how big
| the coins are? There will have to be room for one per header in Mixmaster.
| Do they vary in size, or are all coins identical? There is so much stuff to
| try to keep track of all at once! :/

	If the coin is bigger than a Mix header has room for, does it
have room for an arbitrary token?

	I send a message to the mixmaster I'd like to use, containing
a coin and a large arbitrary number.  I then put that number in a list
I maintain of the tokens I can spend with that mixmaster.

	The mixmaster cashes the coin at once[1], and puts my number
into a list of 'paid' tokens it will accept.

	When I want to spend the token, I put that in the message
header block.   Since its smaller than the coin, its easier to put in
the header than the coin.

	This scheme also reduces mapability between the coin and the
message, since they are not strongly correlated in time as they would
be if they were included in the message.  This seems to be a stronger
win than the size benefit that caused me to suggest this.

	[1] Other than the time mapping win, I could also see spending
a few bucks at the start of each month to be able to use any
mixmaster.  The mixmasters would, by cashing my coins early, win on
the float between the time they get my money and the time they provide
service.  Icing on the cake.

Adam

-- 
"It is seldom that liberty of any kind is lost all at once."
					               -Hume