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-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1YaoGQ-0006Xe-Jd for bitcoin-development@lists.sourceforge.net; Wed, 25 Mar 2015 16:34:42 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.223.177 as permitted sender) client-ip=209.85.223.177; envelope-from=gmaxwell@gmail.com; helo=mail-ie0-f177.google.com; Received: from mail-ie0-f177.google.com ([209.85.223.177]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1YaoGP-0005TV-MF for bitcoin-development@lists.sourceforge.net; Wed, 25 Mar 2015 16:34:42 +0000 Received: by iecvj10 with SMTP id vj10so26507637iec.0 for ; Wed, 25 Mar 2015 09:34:36 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.42.89.200 with SMTP id h8mr18751606icm.48.1427301276310; Wed, 25 Mar 2015 09:34:36 -0700 (PDT) Received: by 10.107.6.133 with HTTP; Wed, 25 Mar 2015 09:34:36 -0700 (PDT) In-Reply-To: <55121611.1030104@thinlink.com> References: <55121611.1030104@thinlink.com> Date: Wed, 25 Mar 2015 16:34:36 +0000 Message-ID: From: Gregory Maxwell To: Tom Harding Content-Type: text/plain; charset=UTF-8 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 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (gmaxwell[at]gmail.com) -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: 1YaoGP-0005TV-MF Cc: Bitcoin Development Subject: Re: [Bitcoin-development] Address Expiration to Prevent Reuse 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: Wed, 25 Mar 2015 16:34:42 -0000 On Wed, Mar 25, 2015 at 1:57 AM, Tom Harding wrote: > The idea of limited-lifetime addresses was discussed on 2014-07-15 in > > http://thread.gmane.org/gmane.comp.bitcoin.devel/5837 > > It appears that a limited-lifetime address, such as the fanciful > > address = 4HB5ld0FzFVj8ALj6mfBsbifRoD4miY36v_349366 Assuming the sender is not an uncooperative idiot, you can simply include expiration information and the sender can refuse to send after that time. If the sender is an uncooperative idiot, they can always change your target and send anyways. This would seem to work nearly as well as the non-reorg safe network impacting version, and yet has no cost beyond the extra size is communicating the limit. > Block containing tx invalid if a prior confirmed tx has paid address Requires a unprunable verification state.