On Friday, April 25, 2003, at 03:01 PM, Patrick Chkoreff wrote:
The question of whether digital notes can circulate in the wild without server contact but with the ability to identify double-spenders later is up for grabs. Hettinga likes that feature for intrinsic reasons having nothing to do with network reliability or ubiquity. I find it a bit appealing myself because it can help support small social nets of accountability. I have not reviewed the math in detail, but am I to understand that under this protocol ONLY double-spenders can be identified? That is, if you do not double-spend can you be guaranteed anonymity from other recipients down the spend chain?
Obviously those in the know share a common threat model that demands blinding. Certainly that has serious implications for the server. In a non-blinded system you can just store a small number of unspent coins and the server can do tricks like include an lseek number in the coin data to make lookup extremely fast. But nobody wants an non-blinded system. Consequently, the server must store a large number of spent coins and because coin identifiers are created randomly out in the wild there is no convenient embedded lseek number. But yes, it is extremely cool that you can get the bank's signature on X without actually revealing X to the bank.
Regarding "digital notes circulating in the wild without server contact," you need to look at some of the articles here (Cypherpunks) from around 1994-97 on "money changing." Cf. articles by Doug Barnes, Ian Goldberg, myself, and others. Accessible via Google. Basically, there is no reason why intermediaries will not develop who agree to take in digital money and issue new digital money, for a fee. The operation of making change is just this. In principle, and probably fairly quickly in practice, the connection with an "issuing bank" (whatever that strange thing may be) is not needed often. "Everyone a moneychanger" and "agnostic" systems work for reasons that would take a lot of time to get into. Several dozen articles, as noted above, get into this. Having a solid, robust, core system of first-class objects is a step we haven't had. The Mark Twain Bank system was too expensive to do experiments with (and didn't last long enough), and so on for other toy systems. --Tim May "He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." -- Nietzsche