Michael_Heyman writes:
Finney, Hal (CR):
The problem is that if the source code you are purchasing is bogus, or if the other side doesn't come through, you're screwed because you've lost the value of the torn cash. The other side doesn't gain anything by this fraud, but they harm you, and if they are malicious that might be enough.
Quick fix for seller incentive: the seller rips some amount of their own cash in such a way that they cannot recover it unless the buyer provides the remainder of the buyer's ripped cash.
Yes, I'm looking at ideas like this for ecash gambling, but you have a who-goes-first problem. One side or the other has to "rip" their own cash first, and then the other side can just go away and leave the first side screwed. The act of ripping cash is relatively atomic and involves a transaction with the ecash mint, so they can't both do it at the same time. I guess the best fix is for each side to rip a little bit of cash at a time, so that the guy who goes first only loses a trivial amount if the other side aborts. Then after a few rounds both sides are sunk pretty deep and both have a strong incentive to complete the transaction. Hal