On Tue, 9 Apr 2002, Anonymous wrote: > Are you saying that if Alice pays Bob, he can anonymously exchange the > coins and end up with new fresh coins with ALICE's identity in them? > That's great, he can double spend all he wants and she ends up going > to the pokey. No thanks.
Brands' paper that Adam refers to says that you can't double spend to begin with. That's in the first intro paragraph, I haven't read much else yet. But let's take the smart card idea one step towards "real" money. What makes the money real? The fact that a government produced it ( or better, people believe whoever produced it will keep their promise). So if the card is produced by a trusted party, and you can't actually double spend (especially if you don't have access to the hardware), then anonymous cash transfer off line can work. But the trick here is the trusted computing device - it *is* money. People can certainly counterfeit it, and the technology for detecting that will be fun, but the basic principle is similar to real cash. Each device can have a serial number (just like real bills do) but there's no reason to tie a device to any particular person, and people can trade devices or transfer amounts between them as they please. Patience, persistence, truth, Dr. mike
