From mboxrd@z Thu Jan 1 00:00:00 1970 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 1VdNNt-0005i8-6d for bitcoin-development@lists.sourceforge.net; Mon, 04 Nov 2013 16:52:13 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of petertodd.org designates 62.13.149.80 as permitted sender) client-ip=62.13.149.80; envelope-from=pete@petertodd.org; helo=outmail149080.authsmtp.com; Received: from outmail149080.authsmtp.com ([62.13.149.80]) by sog-mx-1.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1VdNNs-0002zo-9j for bitcoin-development@lists.sourceforge.net; Mon, 04 Nov 2013 16:52:13 +0000 Received: from mail-c235.authsmtp.com (mail-c235.authsmtp.com [62.13.128.235]) by punt10.authsmtp.com (8.14.2/8.14.2) with ESMTP id rA4GpxQf027511; Mon, 4 Nov 2013 16:51:59 GMT 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 rA4GpqZ1081732 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Mon, 4 Nov 2013 16:51:55 GMT Date: Mon, 4 Nov 2013 11:51:52 -0500 From: Peter Todd To: Ittay Message-ID: <20131104165152.GA3240@petertodd.org> References: <20131104142621.GA2190@petertodd.org> <20131104150406.GA2566@petertodd.org> <20131104154639.GB2759@petertodd.org> <20131104160716.GA3052@petertodd.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="zYM0uCDKw75PZbzx" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-Server-Quench: 6989e2d9-4571-11e3-b802-002590a15da7 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aQdMdgYUFloCAgsB AmUbWlJeVVx7XGY7 ag1VcwRfa1RMVxto VEFWR1pVCwQmQ20F cV5fOBhyfwRBe3w+ ZEVnXHAVWk1yfBN/ FkdJEWgBZHphaTUc TRJQdwFJcANIexZF O1F6ACIKLwdSbGoL NQ4vNDcwO3BTJTpY RgYVKF8UXXNDNyMg QFUNEDMiB0QZSil7 Kh0gJ0RUFk8aMU81 N1ZJ X-Authentic-SMTP: 61633532353630.1023:706 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. 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[URIs: petertodd.org] X-Headers-End: 1VdNNs-0002zo-9j Cc: Bitcoin Dev , Emin =?iso-8859-1?B?R/xu?= Sirer Subject: Re: [Bitcoin-development] Auto-generated miner backbone 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: Mon, 04 Nov 2013 16:52:13 -0000 --zYM0uCDKw75PZbzx Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Nov 04, 2013 at 11:24:33AM -0500, Ittay wrote: > Yes - this is for the mailing list. >=20 > Regarding the algorithm - as we explain in the paper, as long as the > attacker is way ahead - the others can mine on whatever they like. Doesn't > really matter. Once they almost close the gap (and they will, because > they're the majority), leaving only 1 block lead, the selfish miners > publish their secret blocks, loose their lead, but win the entire secret > chain. The honest miners thus loose all the work they did so far. It > doesn't really matter how the honest miners waste their time. Yes, they lose their work, but that's irrelevant: what's important is eventually Alice runs out of secret blocks and then has no advantage over the other miners. In your paper Alice created her lead by exploiting the fact that not all of the hashing power was working to extend the same block due to the "first-wins" rule. With my solution that situation doesn't happen in the first place: forks are resolved quickly because both sides have both forks, and consensus on which one is the winner is achieved very quickly by proving which side has the majority of hashing power through near-target PoW solutions. With the majority of hashing power in consensus and working to extend the same block there's nothing Alice can do to get ahead, defeating the attack. --=20 'peter'[:-1]@petertodd.org 0000000000000008adb581077dcfa0bf067a4ee010fbabb92d136292625b2299 --zYM0uCDKw75PZbzx Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iQEcBAEBCAAGBQJSd9CoAAoJEBmcgzuo5/CF43UH/Rys/GWFjien3u9niNaRzJNC 4ahjqd4pV4e4sVzbBGe+uyXatzUDcMZltcvP4v6VS8x+9Q9oYTr8/1fIYbbDum8Z tdpuJfUrYw7eXja7MA3+8KNIol+JvJnmKOK1Vta9AgpJddKZtWVQlhdE5fV9rkg2 YOUzNcLc+gXvATmif9L6HZaCeEtgW58rr8GXG068aRkm+ajQKAnfZKrjibuiG5VH S+mAzd5HZkrQfFCBTSxCjmOJLY5qqM5VOo2f5yW5R1OT4YzOXdsX5CaPIA/Ujmmw y2sYN2m/z1LrIR2G9EqrVA5lU/UEXTUPb3xLOZSQAQgDKAn9IxgFt4Ci8LFn6Ok= =jHSv -----END PGP SIGNATURE----- --zYM0uCDKw75PZbzx--