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-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Wwdrh-0005ro-WD for bitcoin-development@lists.sourceforge.net; Mon, 16 Jun 2014 20:50:54 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of petertodd.org designates 62.13.149.43 as permitted sender) client-ip=62.13.149.43; envelope-from=pete@petertodd.org; helo=outmail149043.authsmtp.co.uk; Received: from outmail149043.authsmtp.co.uk ([62.13.149.43]) by sog-mx-4.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1Wwdrg-0007Nr-3q for bitcoin-development@lists.sourceforge.net; Mon, 16 Jun 2014 20:50:53 +0000 Received: from mail-c235.authsmtp.com (mail-c235.authsmtp.com [62.13.128.235]) by punt17.authsmtp.com (8.14.2/8.14.2/) with ESMTP id s5GKogKB006390; Mon, 16 Jun 2014 21:50:42 +0100 (BST) Received: from savin (76-10-178-109.dsl.teksavvy.com [76.10.178.109]) (authenticated bits=128) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id s5GKoYii028653 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Mon, 16 Jun 2014 21:50:37 +0100 (BST) Date: Mon, 16 Jun 2014 16:50:41 -0400 From: Peter Todd To: Daniel Rice Message-ID: <20140616205041.GA21784@savin> References: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="n8g4imXOkfNTN/H1" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-Server-Quench: df61d414-f597-11e3-b396-002590a15da7 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR bgdMdwQUEkAaAgsB AmIbWVVeVV17Wms7 bAxPbAVDY01GQQRq WVdMSlVNFUsrBGt6 WXdHCxlwfwNDezBy YERhXj4PCkJ7IUJ8 RlMCEGQBeGZhPWMC AkNRcR5UcAFPdx8U a1UrBXRDAzANdhES HhM4ODE3eDlSNilR RRkIIFQOdA4lHzIx QxEeDH0lGksJXG09 KAZuJlMXEUANKEw2 MEksVRoZNQQOAwtC fQlGBylXJkMETjYq CgUSUlMXCjRbXSpR GXUA X-Authentic-SMTP: 61633532353630.1023:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 76.10.178.109/587 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 SPF_PASS SPF: sender matches SPF record X-Headers-End: 1Wwdrg-0007Nr-3q Cc: Bitcoin Dev , Lawrence Nahum Subject: Re: [Bitcoin-development] Fidelity bonds for decentralized instant confirmation guarantees 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, 16 Jun 2014 20:50:54 -0000 --n8g4imXOkfNTN/H1 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 16, 2014 at 01:37:52PM -0700, Daniel Rice wrote: > True, that would work, but still how are you going to bootstrap the trust? > TREZOR is well known, but in a future where there could be 100 different > companies trying to release a similar product to TREZOR it seems like one > company could corner the market by being the only one that is an accepted > instant provider at most vendors. It seems to encourage monopoly unless > there is a standard way to bootstrap trust in your signature. You can always use fidelity bonds, or as I called it at the time(1), "Trusted identities": Lets suppose Alice has some bitcoins held at bitcoin address A. She wants to establish trust in the "identity" associated with the ECC keypair associated with A, for instance for the purpose of having other users trust her not to attempt to double spend. Since the trust she seeks is financial in nature, she can do this by valuing the identity associated with A, by delibrately throwing away resources. A simple way to do this would of course be to transfer coins to a null address, provably incurring a cost to her. A more socially responsible way would be for her to create a series of transactions that happen to have large, and equal, transaction fees. Bitcoin makes the assumption that no one entity controls more than 50% of the network, so if she makes n of these transactions consecutively, each spending m BTC to transaction fees, there is a high probability that she has given up at least n/2 * m BTC of value. This of course is all public knowledge, recorded in the block chain. It also increases the transaction fees for miners, which will be very important for the network in the future. Now Bob can easily examine the block chain, and upon verifying Alice's trust purchase, can decide to accept a zero-confirmation transaction at face value. If Alice breaks that promise, he simply publishes her signed transaction proving that Alice is a fraudster, and future Bob's will distrust Alice's trusted identity, thus destroying the value needed to create it. In effect, we now have a distributed green address system. Note that the second paragraph is seriously obsolete - better to either use announce-commit sacrifices, or much preferably, simple destruction of coins. (sacrifice to fees encourages mining centralization for obvious reasons) 1) "[Bitcoin-development] Trusted identities", Apr 26th 2012, Peter Todd, http://www.mail-archive.com/bitcoin-development%40lists.sourceforge.net/= msg01005.html Incidentally, my first post to this mailing list! --=20 'peter'[:-1]@petertodd.org 000000000000000058ca7ee3a40438ea5a96e499910638352468c6d69abdb226 --n8g4imXOkfNTN/H1 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) iQGrBAEBCACVBQJTn1icXhSAAAAAABUAQGJsb2NraGFzaEBiaXRjb2luLm9yZzAw MDAwMDAwMDAwMDAwMDA1OGNhN2VlM2E0MDQzOGVhNWE5NmU0OTk5MTA2MzgzNTI0 NjhjNmQ2OWFiZGIyMjYvFIAAAAAAFQARcGthLWFkZHJlc3NAZ251cGcub3JncGV0 ZUBwZXRlcnRvZC5vcmcACgkQJIFAPaXwkfsi+gf/fUtrKJFBP94dEn22EQJ5Jc9r CI4Sb/zuzUiteirnV2CImBUY0xP/e5ohKNz1O4+6ulwIuUrTWYuOL2P+t2LOmpqV 6teSWnM19DSKqFrAD/UN1KGp1q+pzs62fgw9z58oc6EmRZ9aNU5gCE9MEa96evEE 51cACpW1nle8ZQqDmexkda4MHYMSDvWsYiUocGFI+OHJEQsOBEZ25+iz8Nc27Wq5 94yAYpDvzj9IpjbsJM+xgHvvgMMsJmMvg1LGjgKpWwYXgzcPdnZawLobbZzVH4eo VSZSBLbEJODYDhpMl1UA5ogkVI/IldKL1E0hEfIJVnoUi49bUiCKeMzRrUj8Bg== =VSVN -----END PGP SIGNATURE----- --n8g4imXOkfNTN/H1--