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 1TdPiS-0003CH-72 for bitcoin-development@lists.sourceforge.net; Tue, 27 Nov 2012 18:17:04 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.214.175 as permitted sender) client-ip=209.85.214.175; envelope-from=mh.in.england@gmail.com; helo=mail-ob0-f175.google.com; Received: from mail-ob0-f175.google.com ([209.85.214.175]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1TdPiM-0002WE-Tz for bitcoin-development@lists.sourceforge.net; Tue, 27 Nov 2012 18:17:04 +0000 Received: by mail-ob0-f175.google.com with SMTP id vb8so11704216obc.34 for ; Tue, 27 Nov 2012 10:16:53 -0800 (PST) MIME-Version: 1.0 Received: by 10.60.31.51 with SMTP id x19mr13405570oeh.25.1354040213640; Tue, 27 Nov 2012 10:16:53 -0800 (PST) Sender: mh.in.england@gmail.com Received: by 10.76.128.139 with HTTP; Tue, 27 Nov 2012 10:16:53 -0800 (PST) In-Reply-To: <201211271726.56370.andyparkins@gmail.com> References: <201211271703.39282.andyparkins@gmail.com> <201211271726.56370.andyparkins@gmail.com> Date: Tue, 27 Nov 2012 19:16:53 +0100 X-Google-Sender-Auth: YJVqV4qTbfngkVO-BkTI33-gMSs Message-ID: From: Mike Hearn To: Andy Parkins Content-Type: text/plain; charset=UTF-8 X-Spam-Score: -1.4 (-) 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 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (mh.in.england[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 AWL AWL: From: address is in the auto white-list X-Headers-End: 1TdPiM-0002WE-Tz Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Payment Protocol Proposal: Invoices/Payments/Receipts 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: Tue, 27 Nov 2012 18:17:04 -0000 > That hash would then be reported via some secure channel outside of bitcoin's > domain. OK, I see. I guess that could be a reasonable fallback for the case where you have a secure channel. > I don't understand what the relevance of multi-factor is to invoices? Yes, exactly. It's about paying who you think you're paying (when you confirm on a second uncompromised device).