On Sun, Dec 21, 2014 at 11:57:51AM +0800, Mark Friedenbach wrote: > On Sat, Dec 20, 2014 at 10:48 PM, Peter Todd wrote: > > > However the converse is not possible: anti-replay cannot be used to > > implement proof-of-publication. Knowing that no conflicting message > > exists says nothing about who be in posession of that message, or > > indeed, any message at all. Thus anti-replay is not sufficient to > > implement other uses of proof-of-publication such as decentralized > > exchange³. > > > > I think you are trying to say something more specific / limited than that, > and I suggest you adjust your wording accordingly. Decentralized exchange > would be possible today with vanilla bitcoin using SIGHASH_SINGLE if only > the protocol supported multiple validated assets (which it could, but > doesn't). Rather straightforward further extensions to the protocol would > enable market participants to use a wider class of orders, as well as > enable the buyer rather than the seller to dictate order sizes via partial > redemption, as we demonstrate in our Freimarkets paper. Do you realise that all those Freimarket's uses are either based on proof-of-publication, or insecure due to sybil attacks? -- 'peter'[:-1]@petertodd.org 000000000000000017d70ee98f4cee509d95c4f31d5b998bae6deb09df1088fc