From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1UaPpg-00069x-0d for bitcoin-development@lists.sourceforge.net; Thu, 09 May 2013 12:20:24 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of petertodd.org designates 62.13.149.56 as permitted sender) client-ip=62.13.149.56; envelope-from=pete@petertodd.org; helo=outmail149056.authsmtp.com; Received: from outmail149056.authsmtp.com ([62.13.149.56]) by sog-mx-1.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1UaPpe-0005Te-Tm for bitcoin-development@lists.sourceforge.net; Thu, 09 May 2013 12:20:23 +0000 Received: from mail-c232.authsmtp.com (mail-c232.authsmtp.com [62.13.128.232]) by punt10.authsmtp.com (8.14.2/8.14.2/Kp) with ESMTP id r49CKAkA012595; Thu, 9 May 2013 13:20:10 +0100 (BST) Received: from savin (76-10-178-109.dsl.teksavvy.com [76.10.178.109]) (authenticated bits=128) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id r49CK5Fx089457 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Thu, 9 May 2013 13:20:08 +0100 (BST) Date: Thu, 9 May 2013 08:20:05 -0400 From: Peter Todd To: Adam Back Message-ID: <20130509122005.GA6645@savin> References: <20130509111913.GA15870@netbook.cypherspace.org> <20130509114605.GA28133@savin> <20130509120722.GA16188@netbook.cypherspace.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="zhXaljGHf11kAtnf" Content-Disposition: inline In-Reply-To: <20130509120722.GA16188@netbook.cypherspace.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-Server-Quench: ca4bdee6-b8a2-11e2-b10b-0025903375e2 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aQdMdgsUFVQNAgsB AmUbWldeUl17WWo7 bAxPbAVDY01GQQRq WVdMSlVNFUsqBRVy fRtoGhl6fgFDfzBx Y0ZrXD4IDUAoIRMo RFMGHTwEeGZhPWIC AkFYJR5UcAFPdx9G aVd6AXFDAzANdhES HhM4ODE3eDlSNilR RRkIIFQOdA4iGHY9 QREeHDwrVVcIXyE6 JBFjIE9ZEkscekQ3 KV8sXF8eLxYOCwpY fQlMG2dfIEZJTjQi DAdTV0oTeAAA X-Authentic-SMTP: 61633532353630.1019:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 76.10.178.109/587 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Score: -1.5 (-) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1UaPpe-0005Te-Tm Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] An initial replace-by-fee implementation is now available X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 09 May 2013 12:20:24 -0000 --zhXaljGHf11kAtnf Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, May 09, 2013 at 02:07:23PM +0200, Adam Back wrote: > I have to say I do not think you want to have it be random as to who gets > paid (by having conflicting double spends floating around with different > payee & change addresses all from the same sending address.) Indeed. That's the point of the blockchain, to take all those potential inconsistencies and vote on a true transaction history to achieve consensus. > About current defacto no replacement: it is the best bitcoin currently ha= s, > and it has value, with it you need to do a net-split to attack eg > 1-confirmation, and this proposal weakens it. Net-splits are possible but > not trivial. This proposal moves them into spec - ie free. Right now we don't have double-spend proof propagation, so the "net-split" attack is actually totally trivial: just broadcast two different, mutually incompatible, transactions at the same time. About half the time the recipient will get the payment, the other half of the time the payment they thought they were going to get is invalidated. It's very, very rare for sites to have protection against that; blockchain.info's shared-send mixer is one of the few exceptions. But the have access to a whole network monitoring service with connections to nodes all over the planet. > About privacy: I think you are going to inherently disclose which is the > change address, because you will decrease the change when you increase the > fee. There is no coin management in the client, and as far as I saw so f= ar, > no privacy management of which coins to reduce coin cross linking. Who's= to > say the client has 100s of times as many coins as the payment. > > If people dont want to reveal which is change and which payment, they need > to put a big enough fee up front based on a margin over prevailing fee > statistics. It's not ideal, but it still protects against after-the-fact blockchain analysis. Statistics is hard - you can't get it right all the time. Besides, what happens when everyone adds a safety margin? Some people can afford to wait, so for them starting at a low bid and raises it makes a lot of sense. > Also if the bids are too flexibly different how do you stop both bids bei= ng > processed (eg one in a block, the next in the next block). Think about that problem a bit harder. :) --=20 'peter'[:-1]@petertodd.org 00000000000000220dc3b283e651068535f8e934096cfef35342bc688d8ee578 --zhXaljGHf11kAtnf Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQEcBAEBCAAGBQJRi5R0AAoJECSBQD2l8JH7/4gIAID/ZYCL+Ec4Z5u02cRJhFX3 4ETNF06m35OvvVqA75dN7tmosxWe+eQhAWNMY/EYhlXzK3JC32TY/DGoNIHJ7bVu EYSyqdoVjYHllVjDZcQAHofe4nVpFuyuOKtAzierGECpY4U11uf1kcsYxnc9vHxf MxtlIICpGKpAQeQu2J29YYfgT/rhdp0WEBxrfo4dXFmUHRZ8BGwUlQSNCGtiWwm7 fdfiZSqXb+ZKwxNGu36TWKazc+re8GhwE8G+vPtT+2vLccf7USNjzdMZg7GBShp+ Zq+SyMYTMoNMU1mqf2m/UstvF5Zd3xgpZXPdxhh1mnc4j6tFuXDXgSD/JcV8muA= =EO6X -----END PGP SIGNATURE----- --zhXaljGHf11kAtnf--