Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Z69lx-0004wY-9E for bitcoin-development@lists.sourceforge.net; Sat, 20 Jun 2015 03:48:49 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of dashjr.org designates 192.3.11.21 as permitted sender) client-ip=192.3.11.21; envelope-from=luke@dashjr.org; helo=zinan.dashjr.org; Received: from zinan.dashjr.org ([192.3.11.21]) by sog-mx-3.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1Z69lv-0000nU-9x for bitcoin-development@lists.sourceforge.net; Sat, 20 Jun 2015 03:48:49 +0000 Received: from ishibashi.localnet (unknown [IPv6:2001:470:5:265:61b6:56a6:b03d:28d6]) (Authenticated sender: luke-jr) by zinan.dashjr.org (Postfix) with ESMTPSA id C4B6A108083A; Sat, 20 Jun 2015 03:48:07 +0000 (UTC) X-Hashcash: 1:25:150620:bitcoin-development@lists.sourceforge.net::RgsY08PLKIIU/aJW:d0TP X-Hashcash: 1:25:150620:voisine@gmail.com::tZkkBx0KwyFXBSLC:E2dh X-Hashcash: 1:25:150620:mark@friedenbach.org::LT2up1kkBym65F4j:aIBAz From: Luke Dashjr To: bitcoin-development@lists.sourceforge.net Date: Sat, 20 Jun 2015 03:48:05 +0000 User-Agent: KMail/1.13.7 (Linux/3.14.41-gentoo; KDE/4.14.3; x86_64; ; ) References: <20150619103959.GA32315@savin.petertodd.org> In-Reply-To: X-PGP-Key-Fingerprint: E463 A93F 5F31 17EE DE6C 7316 BD02 9424 21F4 889F X-PGP-Key-ID: BD02942421F4889F X-PGP-Keyserver: hkp://pgp.mit.edu MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <201506200348.06564.luke@dashjr.org> X-Spam-Score: -1.9 (-) 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 -0.3 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.1 AWL AWL: Adjusted score from AWL reputation of From: address X-Headers-End: 1Z69lv-0000nU-9x Subject: Re: [Bitcoin-development] F2Pool has enabled full replace-by-fee 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: Sat, 20 Jun 2015 03:48:49 -0000 On Saturday, June 20, 2015 1:23:03 AM Aaron Voisine wrote: > They don't need to be made cryptographically safe, they just have to be > safer than, for instance, credit card payments that can be charged back. As > long as it's reasonably good in practice, that's fine. They never will be. You can get a decent rate of success merely by making one transaction propagate fast (eg, 1 input, 1 output) and the other slow (eg, 1000 inputs, 1000 outputs) and choosing your peers carefully. The only reason unconfirmed transactions aren't double spent today is because nobody is seriously *trying*. Luke