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Date: Sun, 21 Dec 2014 02:01:54 -0500
From: Peter Todd <pete@petertodd.org>
To: Mark Friedenbach <mark@friedenbach.org>
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Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] The relationship between
 Proof-of-Publication and Anti-Replay Oracles
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On Sun, Dec 21, 2014 at 02:18:18PM +0800, Mark Friedenbach wrote:
> Care to expand?
>=20
> 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 t=
he
> counter-party to the order doesn't care if they all came from the same
> person or not.
>=20
> Can you explain what it is you are objecting to?

Read my paper=B9 - 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 dept=
h,
   Peter Todd, Feb 9th 2014,
   http://www.mail-archive.com/bitcoin-development%40lists.sourceforge.net/=
msg03892.html

--=20
'peter'[:-1]@petertodd.org
000000000000000000c879729eae178096b092248706a407ec1b18eb62a792e9

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