On Sun, Dec 21, 2014 at 02:18:18PM +0800, Mark Friedenbach wrote: > Care to expand? > > Freimarkets does not require proof of publication of bids or asks, which > are distributed out of band from the block chain until a match is made. It > does not guarantee ordering of market transactions. Indeed, front-running > is embraced as the mechanism for generating miner fees to pay for the > service. Right, so Freimarkets is delibrately insecure. Best of luck on that. > Sybil attacks? I'm not sure what you could be referring to. In Freimarkets > a bid or ask is valid when received; a double-spend is required to cancel > it. You could only flood the network with actual executable orders, and the > counter-party to the order doesn't care if they all came from the same > person or not. > > Can you explain what it is you are objecting to? Read my paperą - proof-of-publication is what allows you to detect front-running robustly within certain parameters. Protecting against that is widely considered to be a very important goal by people actually in finance, to the point where I've had discussions with people where anti-front-running protection might be the *only* thing they use a decentralized system for. 1) Decentralized digital asset exchange with honest pricing and market depth, Peter Todd, Feb 9th 2014, http://www.mail-archive.com/bitcoin-development%40lists.sourceforge.net/msg03892.html -- 'peter'[:-1]@petertodd.org 000000000000000000c879729eae178096b092248706a407ec1b18eb62a792e9