From mboxrd@z Thu Jan 1 00:00:00 1970 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 1XF50d-0000Gz-MQ for bitcoin-development@lists.sourceforge.net; Wed, 06 Aug 2014 17:28:19 +0000 Received: from mail-pa0-f47.google.com ([209.85.220.47]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1XF50c-0008Er-Uc for bitcoin-development@lists.sourceforge.net; Wed, 06 Aug 2014 17:28:19 +0000 Received: by mail-pa0-f47.google.com with SMTP id kx10so3796785pab.20 for ; Wed, 06 Aug 2014 10:28:13 -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=5G+rFYv+vXdtuS9jsteIW23K9/pI9prNWOcaFw+9Fkc=; b=OJ5BMPF/49hgaaMqQ6IgGnShONM2Ox+VROq7ls8nQ4pnGihDpQDuv73S9t9cvCZhRq llBUwT04NkMMkOawKt1tceUKxiyiuvZVtBIn3wjMCpcNhAz5/rLovBxdC4S754bNt5jD OYxL+JyH357URfE5qg6ql7bXgZ49cZ3VyGq+cgThHUzpX5KafYfjmlsIkELnGY3MBaY9 TJUZLgZeyLPvfMa09qZopQzmjhTol2V86j3niKSvMdSrob8rkMYcCs0z67fqy2tDfUfN thme1+763zUP0rb3WQJgPlCXwMDRKuFDe3xf1DNupxpFqWKVdEvS+1cK7XUprH6jTVLD 7sqA== X-Gm-Message-State: ALoCoQniXCJkZxUEJLQCTBdO1lZN6aY0JoxvtgBItJy7gW+jCujQEC9nFag61osvB5XUT4/u/7ZQ X-Received: by 10.66.182.69 with SMTP id ec5mr12468370pac.125.1407345727401; Wed, 06 Aug 2014 10:22:07 -0700 (PDT) Received: from [192.168.127.194] (173-228-106-61.dsl.dynamic.sonic.net. [173.228.106.61]) by mx.google.com with ESMTPSA id f16sm2604595pdm.43.2014.08.06.10.22.03 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 06 Aug 2014 10:22:06 -0700 (PDT) Message-ID: <53E26434.2070502@monetize.io> Date: Wed, 06 Aug 2014 13:21:56 -0400 From: Mark Friedenbach Organization: Monetize.io Inc. User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Tom Harding , Bitcoin Dev References: <53E1A8AF.4030206@thinlink.com> <53E23F49.3020605@thinlink.com> <63a80796-609e-43f5-9280-4cd8cf5d2648@email.android.com> <53E25F8A.5070905@thinlink.com> In-Reply-To: <53E25F8A.5070905@thinlink.com> Content-Type: text/plain; charset=windows-1252 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. X-Headers-End: 1XF50c-0008Er-Uc Subject: Re: [Bitcoin-development] deterministic transaction expiration 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, 06 Aug 2014 17:28:19 -0000 On 08/06/2014 01:02 PM, Tom Harding wrote: > With first-eligible-height and last-eligible-height, creator could > choose a lifetime shorter than the max, and in addition, lock the whole > thing until some point in the future. Note that this would be a massive, *massive* change that would completely break bitcoin output frangibility. Merchants would have to start demanding input history back to a certain depth in order to ensure they are not exposing themselves to undue reorg-expiry risk. There are useful applications of a consensus-enforced expiry, particularly within a private (signed block) side chain, and for that reason it is useful to have a discussion about the merits of an nExpiry field or BLOCK_HEIGHT / BLOCK_TIME opcode, and methods for achieving either. However I don't see this ever becoming part of the public bitcoin network.