Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1WRPaE-0002Ch-9W for bitcoin-development@lists.sourceforge.net; Sat, 22 Mar 2014 17:19:46 +0000 Received: from mail-pd0-f181.google.com ([209.85.192.181]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1WRPaD-0006bY-7p for bitcoin-development@lists.sourceforge.net; Sat, 22 Mar 2014 17:19:46 +0000 Received: by mail-pd0-f181.google.com with SMTP id p10so3606804pdj.12 for ; Sat, 22 Mar 2014 10:19:39 -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:organization:user-agent :mime-version:to:subject:references:in-reply-to:content-type :content-transfer-encoding; bh=lk33cC0lJj0ngROlIULEHM4yeFVLUdGf1p9TE4seMMU=; b=Hj3nsGazqh/eJj5L0AiVLEDGfjZTQYFIfjb41AKx6UMeZbiqph947Cyx8r88o3HQX4 NcJiKtZ22fjk/bhPt3zDXvXWKdLMJyQD+WGh79NE+bPAesYeT/Eomibg57QdAnFlEL6+ BKXPfWzFXF/pqrWfY3/z6KK3pZ/RXlpQyNOkXzwZdsb2DqvAsaZzmDgKi763K3hddD0t 4CNn2So5COXPm8EtdR9YNAYZHQ17PLfQu1AkQq+FILA4Ii5SftUnMEjAft7e8RiYk390 525R2NqwqZIPAe/kB7Hkkj9G3akAg3fwwDwB5Y3Qi2pvXUudkI9zJ6SQYjHqX/cKOVi4 Yt4w== X-Gm-Message-State: ALoCoQmAolPlLRzsMO3VHblvJgTMyfH/z7F7N6vel/fKVLiM7CbmLNsJdqx8ffi2Z5G3Vakvl8b6 X-Received: by 10.66.122.101 with SMTP id lr5mr37988342pab.130.1395507319478; Sat, 22 Mar 2014 09:55:19 -0700 (PDT) Received: from [192.168.127.179] (50-0-36-93.dsl.dynamic.sonic.net. [50.0.36.93]) by mx.google.com with ESMTPSA id x9sm16606800pbu.1.2014.03.22.09.55.18 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sat, 22 Mar 2014 09:55:18 -0700 (PDT) Message-ID: <532DC076.4060007@monetize.io> Date: Sat, 22 Mar 2014 09:55:18 -0700 From: Mark Friedenbach Organization: Monetize.io Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.3.0 MIME-Version: 1.0 To: bitcoin-development@lists.sourceforge.net References: <20140320121221.GA25052@netbook.cypherspace.org> In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 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. -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [209.85.192.181 listed in list.dnswl.org] X-Headers-End: 1WRPaD-0006bY-7p 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 17:19:46 -0000 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.