Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1WRPkI-0003jT-M4 for bitcoin-development@lists.sourceforge.net; Sat, 22 Mar 2014 17:30:10 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.219.43 as permitted sender) client-ip=209.85.219.43; envelope-from=mh.in.england@gmail.com; helo=mail-oa0-f43.google.com; Received: from mail-oa0-f43.google.com ([209.85.219.43]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1WRPkH-0005QI-DS for bitcoin-development@lists.sourceforge.net; Sat, 22 Mar 2014 17:30:10 +0000 Received: by mail-oa0-f43.google.com with SMTP id eb12so4048433oac.16 for ; Sat, 22 Mar 2014 10:30:04 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.60.160.205 with SMTP id xm13mr2740160oeb.50.1395509404085; Sat, 22 Mar 2014 10:30:04 -0700 (PDT) Sender: mh.in.england@gmail.com Received: by 10.76.71.231 with HTTP; Sat, 22 Mar 2014 10:30:03 -0700 (PDT) In-Reply-To: References: <20140320121221.GA25052@netbook.cypherspace.org> <532DC076.4060007@monetize.io> Date: Sat, 22 Mar 2014 18:30:03 +0100 X-Google-Sender-Auth: l3Z_NaSkngvYSky9ZDjXTKyj8gU Message-ID: From: Mike Hearn To: Jeff Garzik Content-Type: multipart/alternative; boundary=089e01176875500f0304f5355adb X-Spam-Score: -0.5 (/) 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 1.0 HTML_MESSAGE BODY: HTML included in message 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: 1WRPkH-0005QI-DS 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 17:30:10 -0000 --089e01176875500f0304f5355adb Content-Type: text/plain; charset=UTF-8 I think it's mostly a UI issue. The recipient needs to understand that what he received is nothing more than an IOU that can be revoked at any time. If the UI makes it clear and the user trusts the sender, no problem. BIP70 would work as before. On Sat, Mar 22, 2014 at 6:24 PM, Jeff Garzik wrote: > 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/ > > > ------------------------------------------------------------------------------ > 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 > --089e01176875500f0304f5355adb Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I think it's mostly a UI issue. The recipient needs to= understand that what he received is nothing more than an IOU that can be r= evoked at any time. If the UI makes it clear and the user trusts the sender= , no problem. BIP70 would work as before.


On Sat, Mar 2= 2, 2014 at 6:24 PM, Jeff Garzik <jgarzik@bitpay.com> wrote:=
One participant, yes. =C2=A0Two participants lacking net would require a serious revisit of BIP 70's security assumptions and some design, at a<= br> minimum.

On Sat, Mar 22, 2014 at 12:55 PM, Mark Friedenbach <mark@monetize.io> 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. =C2=A0Of course you can fin= d locations
>> that lack Internet.
>>
>> Those locations are completely unsuitable to bitcoin transactions,=
>> since the receiver cannot verify double-spending or anything else<= br> >> about the transaction.
>
> ----------------------------------------------------------------------= --------
> Learn Graph Databases - Download FREE O'Reilly Book
> "Graph Databases" is the definitive new guide to graph datab= ases 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-d= evelopment@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitco= in-development



--
Jeff Garzik
Bitcoin core developer and open source evangelist
BitPay, Inc. =C2=A0 =C2=A0 =C2=A0https://bitpay.com/

-----------------------------= -------------------------------------------------
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-develo= pment@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment

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