From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1R7IYK-0007Hb-Fy for bitcoin-development@lists.sourceforge.net; Sat, 24 Sep 2011 03:05:20 +0000 X-ACL-Warn: Received: from rhcavuit02.kulnet.kuleuven.be ([134.58.240.130] helo=cavuit02.kulnet.kuleuven.be) by sog-mx-4.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1R7IYJ-0002Tv-Ba for bitcoin-development@lists.sourceforge.net; Sat, 24 Sep 2011 03:05:20 +0000 X-KULeuven-Envelope-From: sipa@ulyssis.org X-Spam-Status: not spam, SpamAssassin (not cached, score=-48.788, required 5, autolearn=disabled, DKIM_ADSP_CUSTOM_MED 0.00, FREEMAIL_FROM 0.00, KUL_SMTPS -50.00, NML_ADSP_CUSTOM_MED 1.20, T_TO_NO_BRKTS_FREEMAIL 0.01) X-KULeuven-Scanned: Found to be clean X-KULeuven-ID: 41D3D128029.A7673 X-KULeuven-Information: Katholieke Universiteit Leuven Received: from smtps01.kuleuven.be (smtpshost01.kulnet.kuleuven.be [134.58.240.74]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id 41D3D128029 for ; Sat, 24 Sep 2011 05:05:08 +0200 (CEST) Received: from smtp.ulyssis.org (mail.ulyssis.student.kuleuven.be [193.190.253.235]) by smtps01.kuleuven.be (Postfix) with ESMTP id 2563231E71A for ; Sat, 24 Sep 2011 05:05:08 +0200 (CEST) Received: from wop.ulyssis.org (wop.intern.ulyssis.org [192.168.0.182]) by smtp.ulyssis.org (Postfix) with ESMTP id EDD0D1000F for ; Sat, 24 Sep 2011 05:10:09 +0200 (CEST) Received: by wop.ulyssis.org (Postfix, from userid 615) id 164D387C1B2; Sat, 24 Sep 2011 05:05:08 +0200 (CEST) Date: Sat, 24 Sep 2011 05:05:08 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Pieter Wuille To: bitcoin-development@lists.sourceforge.net Message-ID: <20110924030505.GA21292@ulyssis.org> References: <20110923162102.GA13532@ulyssis.org> <4E7CC428.6020500@jerviss.org> <20110923231547.GA28700@ulyssis.org> <201109231922.01269.luke@dashjr.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201109231922.01269.luke@dashjr.org> X-PGP-Key: http://sipa.ulyssis.org/pubkey.asc User-Agent: Mutt/1.5.20 (2009-06-14) X-Spam-Score: 1.2 (+) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (pieter.wuille[at]gmail.com) 0.0 DKIM_ADSP_CUSTOM_MED No valid author signature, adsp_override is CUSTOM_MED 1.2 NML_ADSP_CUSTOM_MED ADSP custom_med hit, and not from a mailing list 0.0 T_TO_NO_BRKTS_FREEMAIL To: misformatted and free email service -0.0 AWL AWL: From: address is in the auto white-list X-Headers-End: 1R7IYJ-0002Tv-Ba Subject: Re: [Bitcoin-development] Beyond IP transactions: towards a bitcoin payment protocol 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, 24 Sep 2011 03:05:20 -0000 On Fri, Sep 23, 2011 at 07:21:58PM -0400, Luke-Jr wrote: > On Friday, September 23, 2011 7:15:48 PM Pieter Wuille wrote: > > What I want to do is to standardize part of that out-of-band communication > > inside a protocol. > > Email and XMPP are suitable. Just sign the message with the "from" key. I don't want to send a mail to you or chat with you when I'm buying something in your webshop. Or do you mean my client does that automatically? Why not through an HTTP connection like the one I'm already using anyway to view the static address on your website? > > The first observation is that if you want a freshly negotiated key each > > time, some form of bidirectional communication is necessary anyway, and a > > static txout template does not suffice anymore. > > False. Deterministic keypairs remove the necessity of bidirectional > communication. A standard for a "public key root" "address" could be > worthwhile. They still require you to give me your public key root, and me to give you the ephemeral private key I generated, optionally together with what I'm paying you for. That's bidirectional communication to me. Agreed, your scheme requires a few steps less, but I believe mine is far more flexible and user-friendly. -- Pieter