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-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1XJZC5-00021d-7P for bitcoin-development@lists.sourceforge.net; Tue, 19 Aug 2014 02:30:41 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of petertodd.org designates 62.13.148.99 as permitted sender) client-ip=62.13.148.99; envelope-from=pete@petertodd.org; helo=outmail148099.authsmtp.net; Received: from outmail148099.authsmtp.net ([62.13.148.99]) by sog-mx-2.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1XJZC3-0004Bv-RO for bitcoin-development@lists.sourceforge.net; Tue, 19 Aug 2014 02:30:41 +0000 Received: from mail-c237.authsmtp.com (mail-c237.authsmtp.com [62.13.128.237]) by punt18.authsmtp.com (8.14.2/8.14.2/) with ESMTP id s7J2UX1c091247 for ; Tue, 19 Aug 2014 03:30:33 +0100 (BST) Received: from petertodd.org (petertodd.org [174.129.28.249]) (authenticated bits=128) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id s7J2UQPo029088 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO) for ; Tue, 19 Aug 2014 03:30:28 +0100 (BST) Date: Mon, 18 Aug 2014 22:30:25 -0400 From: Peter Todd To: bitcoin-development@lists.sourceforge.net Message-ID: <20140819023025.GA3074@petertodd.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="mYCpIKhGyMATD0i+" Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-Server-Quench: c8cebfb7-2748-11e4-9f74-002590a135d3 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVJwpGK10IU0Fd P1hXKl1LNVAaWXld WiVPGEoXDxgzCjYj NEgGOBsDNw4AXgx1 IQ0eXVBSFQF4AR8L BR4UUBE8dgJCZn9y bFhgVm5ZWE1lcE56 XU8aVmp8ZwIBCD8f UklYfwsadARMdlEW YgMqBiVfZngFYX5o WlZqMmx0bDsAdGEN GltQfAobGB1WEmUq bBQFADlnGEwDRiM8 ZwcmLUMYEA4bPw0v KlonVhodPgURDgAW BFxISDNDKlQaDzYs RRtAWlATWCFdTDYU CwclJFBUYHReXSte CwNLURgEFyJCViBM ACxQSSA3ElVhIkMs MyIQWQgA X-Authentic-SMTP: 61633532353630.1024:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 174.129.28.249/587 X-AuthVirus-Status: No virus detected - but ensure you scan with your own anti-virus system. X-Spam-Score: -1.5 (-) 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 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [62.13.148.99 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1XJZC3-0004Bv-RO Subject: [Bitcoin-development] Cloud mining should be using merkle sum trees to prove they aren't doing fractional reserve mining 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: Tue, 19 Aug 2014 02:30:41 -0000 --mYCpIKhGyMATD0i+ Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable A number of people - most recently Gavin Andresen - have speculated that cloud hashing operations may in fact be ponzi schemes that don't actually own the hashing power they claim to own. The claim is that the customers upfront purchase of hashing power is simply kept and used to pay off existing customer profits rather than actually being used to purchase mining equipment. We can use merkle sum trees to detect this fraud cryptographically: 1) Put the MH/s paid for by each account into a merkle sum tree, each with a customer supplied unique identifier. (like their email address) This allows the customer to verify that the hashing power they paid for has been included in the total hashing power claimed. 2) Mark blocks found by the operation publicly so they can be associated with the specific cloud mining operation; putting the merkle sum tree root hash into the coinbase or an OP_RETURN output would be ideal. This allows anyone to verify that the hashing power claimed corresponds to the # of blocks actually found. --=20 'peter'[:-1]@petertodd.org 0000000000000000201d505432d708aa2edb656f6fe34d686b37d4747e5ff389 --mYCpIKhGyMATD0i+ Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQEcBAEBCAAGBQJT8rbBAAoJEBmcgzuo5/CF8zIIANNpWYzw0Ir85Zg6gIr0CWWC k/2IzrQALx9qqSex4lB81wO9VUiCs3p6HE5AFLFJur8dIVZ9F7ArPo4EARHVeq4v AyjN88kwxdJHz2zQOyPV7Rm1o2lIU0eQaP+mBwcGPIbrRJKPFPVL+yFQBYxXyzEB Sku+L5wdbycEOLgWFpSrVci0sj22ouprzlEgVJTG+u8sznfmi2ShPh+2mJs22RXL rUgo81AtZc1UWJEOXKRM9txXabZhSOziVJiX7gAjy7IiE9tyqZcUrRHztJFYlo+o DY1K/gLkOrIZVi2HbFMIb4zav+SQr/4Sftbz8+k6URdaE2FsECsUCEU/5OkvfdY= =cTN/ -----END PGP SIGNATURE----- --mYCpIKhGyMATD0i+--