Your source code, for sale

[Hal Finney]

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

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