Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id A32FEA87 for ; Thu, 23 Feb 2017 18:19:45 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from outmail148114.authsmtp.net (outmail148114.authsmtp.net [62.13.148.114]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id DD28713D for ; Thu, 23 Feb 2017 18:19:44 +0000 (UTC) Received: from mail-c247.authsmtp.com (mail-c247.authsmtp.com [62.13.128.247]) by punt20.authsmtp.com (8.14.2/8.14.2/) with ESMTP id v1NIJX5s009705; Thu, 23 Feb 2017 18:19:33 GMT Received: from petertodd.org (ec2-52-5-185-120.compute-1.amazonaws.com [52.5.185.120]) (authenticated bits=0) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id v1NIJVqW079757 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 23 Feb 2017 18:19:32 GMT Received: from [127.0.0.1] (localhost [127.0.0.1]) by petertodd.org (Postfix) with ESMTPSA id D68FB400A9; Thu, 23 Feb 2017 18:19:30 +0000 (UTC) Received: by localhost (Postfix, from userid 1000) id 08D9520245; Thu, 23 Feb 2017 13:19:30 -0500 (EST) Date: Thu, 23 Feb 2017 13:19:29 -0500 From: Peter Todd To: Chris Priest Message-ID: <20170223181929.GA6268@savin.petertodd.org> References: <20170223011506.GC905@savin.petertodd.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="lrZ03NoBR/3+SXJZ" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) X-Server-Quench: 9f992a4a-f9f4-11e6-bcdf-0015176ca198 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aAdMdAEUHlAWAgsB AmEbWlxeUVR7WmE7 bghPaBtcak9QXgdq T0pMXVMcUgQWeGZn R3keVRB1cgIIfX50 YwhrCHlSXhV+JFsr SxhQCGwHMGF9OjNL Bl1YdwJRcQRMLU5E Y1gxNiYHcQ5VPz4z GA41ejw8IwAXAWx/ Tx0RIEhaZGMxVhIx SREEHCkuGktt X-Authentic-SMTP: 61633532353630.1038:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 52.5.185.120/25 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: Bitcoin Protocol Discussion Subject: Re: [bitcoin-dev] A Better MMR Definition X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 23 Feb 2017 18:19:45 -0000 --lrZ03NoBR/3+SXJZ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Feb 23, 2017 at 09:53:58AM -0800, Chris Priest wrote: > On 2/22/17, Peter Todd via bitcoin-dev > wrote: > > Reposting something that came up recently in a private discussion with = some > > academics: > > > > Concretely, let's define a prunable MMR with the following grammar. This > > definition is an improvement on whats in the python-proofmarshal by > > committing > > to the number of items in the tree implicitly; an obvious max-log2(n)-s= ized > > proof-of-tree-size can be obtained by following the right-most nodes: >=20 > What problem does this try to solve, and what does it have to do with bit= coin? See the discussion on TXO commitments for how MMR's could be used; a better= MMR makes for a better TXO commitment. --=20 https://petertodd.org 'peter'[:-1]@petertodd.org --lrZ03NoBR/3+SXJZ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iQEcBAEBCAAGBQJYryevAAoJECSBQD2l8JH7XJkIAJhRsGxYbDqH1SZJ8/Ca3kVn y5ZxFZlSJaaoJtF24qCsh/aEEN0wRHDAEiH8JVdZLQ6qcUSOtigxzYBkymyNaREq rJC9uV+qMrhkucj2hBmLklflVTtXM4drSK3is/SX5Hr+jMkSyHxkRQopKgU39qiZ 12lGoBVV2IFnD2llhW+VbLBH9lJ2znxMbqLoq8YVnJCKURfvso/r0cYES/Ddmu3U xj2KLTjE1b/WanfsUXXDFNquLJ3QcR9nSvJt31gxAgms4U3f9PtAXarlzNuBMs5M KFYj4q0RMQeACNJLf+Xpb4psOckZsGSSAPW2rrcZoWv88MX3v+URZfMZuM6h9uY= =/OrP -----END PGP SIGNATURE----- --lrZ03NoBR/3+SXJZ--