Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Z4rUB-0000zJ-Mw for bitcoin-development@lists.sourceforge.net; Tue, 16 Jun 2015 14:05:07 +0000 X-ACL-Warn: Received: from mail-pd0-f181.google.com ([209.85.192.181]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1Z4rU7-0005j7-I7 for bitcoin-development@lists.sourceforge.net; Tue, 16 Jun 2015 14:05:07 +0000 Received: by pdbnf5 with SMTP id nf5so15245494pdb.2 for ; Tue, 16 Jun 2015 07:04:57 -0700 (PDT) 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=v39soQtW6rh1ErJUhQVzKqwdIMOnGh0E9l0GB6yOaw0=; b=giOa2stEHtBqSf3GZCIeca0Ax2kMpJ/Fj0FKGvRcNZY/QU2uWQN728R1wlst9UuTv1 yDlQT0cAghfuzUkV5aK/xCVOCxd59YXsCJnr3TVaxBPZdry8Vhs2zB4oXGjpeAmnwg2Y /5TWaCcM0D7J1piAmuWB+QSUU37A17sI/qVjrY26qZFtxigWsGYW1kwBsGms5ASnBjtJ agjjYSJuNafG0a61vqbWdNIcO+50d3UAiu4uxcqEXDxfra4viHP07Avdc/R6zws79cHL D1sdD2t0d5/IgBVPkIW5JMx0p4XP50gN5xyixISB583XByRAqTO+WJDAcweKh7C2iwmw nI+w== X-Gm-Message-State: ALoCoQnd2Yrj+LUOBaOJfn9a1VwUFHd0sfED0+1H/I89iXbDZ5d4FpHXFYKiRjH7U3CzpMt+tEk+ X-Received: by 10.70.130.198 with SMTP id og6mr848190pdb.153.1434463497824; Tue, 16 Jun 2015 07:04:57 -0700 (PDT) Received: from [192.168.1.89] (99-8-65-117.lightspeed.davlca.sbcglobal.net. [99.8.65.117]) by mx.google.com with ESMTPSA id fs16sm1576381pdb.12.2015.06.16.07.04.55 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Jun 2015 07:04:56 -0700 (PDT) Message-ID: <55802D0D.4090506@thinlink.com> Date: Tue, 16 Jun 2015 07:05:01 -0700 From: Tom Harding User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Kalle Rosenbaum References: <557FB36B.1030902@thinlink.com> In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Score: 0.5 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. 0.5 AWL AWL: Adjusted score from AWL reputation of From: address X-Headers-End: 1Z4rU7-0005j7-I7 Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] BIP for Proof of Payment 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, 16 Jun 2015 14:05:07 -0000 On 6/16/2015 5:12 AM, Kalle Rosenbaum wrote: > 2015-06-16 7:26 GMT+02:00 Tom Harding : >> Kalle goes to some trouble to describe how merchants need to ensure th= at >> they only accept a PoP provided as a response to their challenge. >> > Do you mean that it will be hard to explain to merchants that they > must check the nonce in the PoP so that it matches the nonce in the > pop request? Sorry for the idiomatic language. No, I just meant that you have thought it out in detail! You standardize a latent capability of the cryptosystem. It seems very powerful for some classes of users.