From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1YPZVl-0003ww-HE for bitcoin-development@lists.sourceforge.net; Sun, 22 Feb 2015 16:36:05 +0000 X-ACL-Warn: Received: from mail-pa0-f42.google.com ([209.85.220.42]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1YPZVk-0000YQ-9W for bitcoin-development@lists.sourceforge.net; Sun, 22 Feb 2015 16:36:05 +0000 Received: by pabkq14 with SMTP id kq14so21385774pab.3 for ; Sun, 22 Feb 2015 08:35:58 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:message-id:date:from:user-agent:mime-version:to :cc:subject:references:in-reply-to:content-type :content-transfer-encoding; bh=mF+zNO1aXbjdTKPgX9PDDJT8tf/yaJ/EnQGjxSZAM0k=; b=QAvkMLV3xQ9M4FECkq48RnUREKm/0LMT+OgP5CFPQVQ87sYmxEaQiw3HsPDAou1stC qMFsRP5ZJSeSCrxxfiSj5r27gzWz+/y+yb4iX5Q/W8w7irFan7Z1L3XAGinDzU3TKYnM Uub4Hh59pwj+rugB3BAyEfirifXzC6avskfbljoJvdhCWZEqCNCZn2ksGzj1l/sQL/GP WoBVbPvqqGVoNp99PToyjyKLhjdsNiNuD7kkLE1wQUhS+odMk9yA/DlEIF1tMlwdO/VD 7L1zOaSCkYeNpKghseIHwmqjCMNX8V9mRe+BfzVDK4RS3uLTzAmqqOarS1RoPbegZ0gr 6cIw== X-Gm-Message-State: ALoCoQkyU9cnnXULSDbzamfZOw3DVLtsYeSdY084uT4YbmXp9L1+za6qjeGebJ5mXoq2a9YbT13x X-Received: by 10.70.40.209 with SMTP id z17mr12647162pdk.9.1424622958434; Sun, 22 Feb 2015 08:35:58 -0800 (PST) Received: from [192.168.1.89] (99-6-44-248.lightspeed.sntcca.sbcglobal.net. [99.6.44.248]) by mx.google.com with ESMTPSA id d9sm15020518pdk.3.2015.02.22.08.35.57 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 22 Feb 2015 08:35:57 -0800 (PST) Message-ID: <54EA0571.4050107@thinlink.com> Date: Sun, 22 Feb 2015 08:36:01 -0800 From: Tom Harding User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: Peter Todd References: <20150212064719.GA6563@savin.petertodd.org> In-Reply-To: <20150212064719.GA6563@savin.petertodd.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Score: 0.0 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. X-Headers-End: 1YPZVk-0000YQ-9W Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] replace-by-fee v0.10.0rc4 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: Sun, 22 Feb 2015 16:36:05 -0000 On 2/11/2015 10:47 PM, Peter Todd wrote: > My replace-by-fee patch is now available for the v0.10.0rc4 release: > > https://github.com/petertodd/bitcoin/tree/replace-by-fee-v0.10.0rc4 > This patch immediately simplifies successful double-spends of unconfirmed transactions. But the idea that it "gives a path to making zeroconf transactions economically secure" is quite dubious. * You don't provide sufficient means to detect and relay double-spends, which is necessary to trigger a scorched-earth reaction. Not all double-spends will conform to your replacement rules. * Maybe XT nodes would help to overcome this. But meanwhile, in the ANYONECANPAY design, Bob's replacement is a triple-spend. Even XT nodes won't relay it. * It's unclear when, if ever, any senders/receivers will actually try to use scorched-earth as a double-spend deterrent. Also, this patch significantly weakens DoS protections: * It removes the early conflict check, making all conflict processing more expensive * There is no attempt to protect against the same transaction being continually replaced with the fee bumped by a minimal amount.