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-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1WRPfR-00025D-OH for bitcoin-development@lists.sourceforge.net; Sat, 22 Mar 2014 17:25:09 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of bitpay.com designates 209.85.213.47 as permitted sender) client-ip=209.85.213.47; envelope-from=jgarzik@bitpay.com; helo=mail-yh0-f47.google.com; Received: from mail-yh0-f47.google.com ([209.85.213.47]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1WRPfR-0005XQ-0T for bitcoin-development@lists.sourceforge.net; Sat, 22 Mar 2014 17:25:09 +0000 Received: by mail-yh0-f47.google.com with SMTP id 29so3683435yhl.20 for ; Sat, 22 Mar 2014 10:25:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc:content-type; bh=NNNA63kB+BrJ68id9zq2hS1AJvGuDPK4FXQI5DuRecU=; b=SVFHrRCQdlZDR6GZwHKyez7LFeHpWFYPukrMI0j/hL9Z7PzfqFucqyFfciHmc3tCcE /4W4HK5UOWhB7op0aiQwJM/7t/gbtgKiEYzQDDOv0EGv9EJW2g/McCkGQU4kf0VNoY53 Zu/vcz0tTAcNOGNWh6vvDrmmp9QdSeBBVT0eOZjLskDn5GljNJHaMoto694yVqHH67Jw 91jMW9aAd4k9mv6T8bYSbjbm1l0L80nbo9ZUs142RHlZq7zi5/QJlwSqlI1Tq0IGF7eo Fkzns8d497zAIycxJJWkFC7BfItn4wNv9ti20a86+LDQ6F7PsY98nE3940r5I3qkhpnw X58w== X-Gm-Message-State: ALoCoQmGQo/Rl8xCZIQ2f+f5Ezuj/LWi6WpH+sa9lM5VaW9pDtYLuUWoFqrX09mLWluNVy62J1Ux X-Received: by 10.236.112.39 with SMTP id x27mr3246084yhg.103.1395509103452; Sat, 22 Mar 2014 10:25:03 -0700 (PDT) MIME-Version: 1.0 Received: by 10.170.162.214 with HTTP; Sat, 22 Mar 2014 10:24:43 -0700 (PDT) In-Reply-To: <532DC076.4060007@monetize.io> References: <20140320121221.GA25052@netbook.cypherspace.org> <532DC076.4060007@monetize.io> From: Jeff Garzik Date: Sat, 22 Mar 2014 13:24:43 -0400 Message-ID: To: Mark Friedenbach Content-Type: text/plain; charset=ISO-8859-1 X-Spam-Score: -1.6 (-) 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 -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 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 X-Headers-End: 1WRPfR-0005XQ-0T Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Payment Protocol for Face-to-face Payments 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, 22 Mar 2014 17:25:09 -0000 One participant, yes. Two participants lacking net would require a serious revisit of BIP 70's security assumptions and some design, at a minimum. On Sat, Mar 22, 2014 at 12:55 PM, Mark Friedenbach wrote: > Jeff, there are *plenty* of places that lack local Internet access for > one or both participants. > > Obviously making the case where both participants lack access to the > bitcoin network is difficult to secure, but not impossible (e.g. use a > telephany-based system to connect to a centralized double-spend > database, as VISA does). > > I expect the case where one participant has Internet access (the > merchant) and the other does not to be very, very common. The majority > of transactions I do on a daily basis are like this, and I live in > Silicon Valley! > > On 03/22/2014 09:35 AM, Jeff Garzik wrote: >> Let's not pull out silly examples. Of course you can find locations >> that lack Internet. >> >> Those locations are completely unsuitable to bitcoin transactions, >> since the receiver cannot verify double-spending or anything else >> about the transaction. > > ------------------------------------------------------------------------------ > Learn Graph Databases - Download FREE O'Reilly Book > "Graph Databases" is the definitive new guide to graph databases and their > applications. Written by three acclaimed leaders in the field, > this first edition is now available. Download your free book today! > http://p.sf.net/sfu/13534_NeoTech > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- Jeff Garzik Bitcoin core developer and open source evangelist BitPay, Inc. https://bitpay.com/