On Fri, May 09, 2014 at 05:15:52PM +0200, Mike Hearn wrote: > > > > Of course we quickly rejected the idea of depending solely on a > > communications backchannel to retrieve funds. Any communications medium > > that isn't the blockchain makes the payment non-atomic > > > Yes, I know you rejected this design, which is why I'm now proposing it > instead. I think you made the wrong design call, but at any rate, it's > something reasonable people can disagree on. > > Payment messages are sent directly to the merchant, who takes > responsibility for broadcast. Once you delivered transactions to the > merchant successfully, from your perspective the payment is made. A good > store and forward network doesn't allow messages to go missing - email is > an example of that (ignoring spam filters that explicitly want messages to > go missing). It either gets delivered or it doesn't. So I'm not worried > about atomicity. Ah, you're still misunderstanding my point: You can get atomicity in the worst-case where the communications medium fails *and* stealth payments that use up no extra space in the blockchain. This gives you the best of both worlds. I haven't yet specified that mode of operation in the current draft stealth address standard, however I do plan on adding it. Notably the standard is designed to allow exactly that feature to be added in a backwards compatible way - senders who don't implement that feature, or choose not to use it, simply fall back to op-return. -- 'peter'[:-1]@petertodd.org 00000000000000004d25218420094fda0891fe1d734e1a8df581bd6de7f2d0cd