Quote from: gmaxwell on March 24, 2014, 11:36:53 PM

Quote from: quannabe on March 24, 2014, 11:18:28 PM

So, we have a refund for the TX_0 transaction, but don't announce it. If Carol announces a transaction that spends TX_0, and then announces a refund for TX_1, how does the refund work to prevent cheating? Isn't TX_0 spent at that point?

TX_0's output is a 2-of-2 multisignature output. It can't be spent unilaterally, the other user must sign it too. Does that answer your question?

I think my confusion stems from my use case: where Alice and Bob are the same person (2-party with only Alice & Carol) who will calculate the X Value?

Doesn't one of them knowing this value before the other allow someone to cheat?

Or, would a 3rd party need to generate X, calculate and send Alice & Carol HX, and release X after they have exchanged TX_2 & TX_3?