Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1UzSmJ-00042N-Gd for bitcoin-development@lists.sourceforge.net; Wed, 17 Jul 2013 14:32:27 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of mac.com designates 17.158.236.236 as permitted sender) client-ip=17.158.236.236; envelope-from=gronager@mac.com; helo=nk11p04mm-asmtp001.mac.com; Received: from nk11p04mm-asmtp001.mac.com ([17.158.236.236]) by sog-mx-3.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1UzSmH-0007fs-E4 for bitcoin-development@lists.sourceforge.net; Wed, 17 Jul 2013 14:32:27 +0000 Received: from macgronager.home (pool-108-21-220-181.nycmny.fios.verizon.net [108.21.220.181]) by nk11p04mm-asmtp001.mac.com (Oracle Communications Messaging Server 7u4-26.01(7.0.4.26.0) 64bit (built Jul 13 2012)) with ESMTPSA id <0MQ3008ME4D6NB70@nk11p04mm-asmtp001.mac.com> for bitcoin-development@lists.sourceforge.net; Wed, 17 Jul 2013 14:31:57 +0000 (GMT) X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.10.8794,1.0.431,0.0.0000 definitions=2013-07-17_06:2013-07-17, 2013-07-17, 1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 ipscore=0 suspectscore=2 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=6.0.2-1305010000 definitions=main-1307170092 Content-type: multipart/signed; boundary="Apple-Mail=_6CBFD6B8-9F70-424E-80C8-8ED706EA8BCA"; protocol="application/pgp-signature"; micalg=pgp-sha1 MIME-version: 1.0 (Mac OS X Mail 6.5 \(1508\)) From: Michael Gronager In-reply-to: <3DB67FAF-E113-47FE-9043-C22D0F5A4F4A@grabhive.com> Date: Wed, 17 Jul 2013 10:31:52 -0400 Message-id: <16E9C860-51CA-4274-B852-A816D12B6A5B@mac.com> References: <3E7894A0-06F3-453D-87F8-975A244EBACF@include7.ch> <2BDA0943-22BB-4405-9AF0-86FB41FD04A6@include7.ch> <2F20A509-13A9-4C84-86D7-A15C21BACD53@include7.ch> <2A1C412D-414E-4C41-8E20-F0D21F801328@grabhive.com> <8EE501AA-1601-4C28-A32E-80F17D219D3A@grabhive.com> <20130717105853.GA10083@savin> <3DB67FAF-E113-47FE-9043-C22D0F5A4F4A@grabhive.com> To: Wendell X-Mailer: Apple Mail (2.1508) X-Spam-Score: -1.9 (-) 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 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (gronager[at]mac.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.4 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain X-Headers-End: 1UzSmH-0007fs-E4 Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] SPV bitcoind? (was: Introducing BitcoinKit.framework) 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, 17 Jul 2013 14:32:27 -0000 --Apple-Mail=_6CBFD6B8-9F70-424E-80C8-8ED706EA8BCA Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Hi Wendell, What Peter describes (a hash of the current set of UTXOs as part of the = coinbase) is already implemented in libcoin, on which you can easily = build both a bitcoind and any client. Libcoin is a library originally = based on the satoshi client, and as such it is compatible/replacable = with "master".=20 Have a look at github.com/libcoin/libcoin and look in the = BlockChain.h/cpp and the MerkleTrie classes then you can see how it = works. What is missing from libcoin is a scheme to bootstrap the hash of UTXOs, = there is some stub code for a p2pool like mining scheme ensuring several = UTXO hashes every 10 minutes, but I will not have time to finalize it = the first few months - anyone are of course welcome to help out ;) Michael On 17/07/2013, at 09:37, Wendell wrote: > Peter, >=20 > This sounds like a _very_ good idea for a desktop client, and probably = acceptable to users so long as we take available disk space into = consideration, and only ever use a fraction of it. >=20 > Will you implement this? >=20 > -wendell >=20 > grabhive.com | twitter.com/grabhive >=20 > On Jul 17, 2013, at 12:58 PM, Peter Todd wrote: >=20 >> So what's useful about that? Basically it means your node starts with >> the same security level, and usefulness to the network, as a SPV = node. >> But over time you keep downloading blocks as they are created, and = with >> whatever bandwidth you have left (out of some user-configurable >> allocation) you download additional blocks going further and further >> back in time. Gradually your UTXO set becomes more complete, and over >> time you can verify a higher and higher % of all valid transactions. >> Eventually your node becomes a full node, but in the meantime it was >> still useful for the user, and still contributed to the network by >> relaying blocks and an increasingly large subset of all transactions. >> (optionally you can store a subset of the chain history too for other >> nodes to bootstrap from) You've also got better security because you >> *are* validating blocks, starting off incompletely, and increasingly >> completely until your finally validating fully. Privacy is improved, = for >> both you and others, by mixing your transactions with others and = adding >> to the overall anonymity set. >>=20 >> In the future we'll have miners commit a hash of the UTXO set, and = that >> gives us even more options to, for instance, have relayed = transactions >> include proof that their inputs were valid, allowing all nodes to = relay >> them safely. >=20 > = --------------------------------------------------------------------------= ---- > See everything from the browser to the database with AppDynamics > Get end-to-end visibility with application monitoring from AppDynamics > Isolate bottlenecks and diagnose root cause in seconds. > Start your free trial of AppDynamics Pro today! > = http://pubads.g.doubleclick.net/gampad/clk?id=3D48808831&iu=3D/4140/ostg.c= lktrk_______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development --Apple-Mail=_6CBFD6B8-9F70-424E-80C8-8ED706EA8BCA Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP using GPGMail -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.19 (Darwin) iQEcBAEBAgAGBQJR5qrZAAoJEKpww0VFxdGRpPsIAJyvVdrVunnh9f+0PP5QaeMH 2OaIvx2MnYd8APNc9Q8Px1sU3rmbSiwsQi9mLSB/kX4a54VxSka1OtYO/pece8c+ gS1QvVWPRDldqO8OAVWmTAKA0KFvMSIB1BPqwT6zVCFvCNFvXkKykW0OjAflxB4N qdxmviOrpSM4rJZl++kZGxUrIP+AVqUsVviLag2XKKDs3VEIedkEteHDrY36u1qi 8heFNtJRtK7R0etn2mQ6CGeAACXUtoYVq8Xlo2xZa2ZQsQw9HcI7LAkztrvaBYTC Bc9g/zays6fI6y7iylCd4a6vqTUOW9sLgJc93585YosGzUwo4UPWpqDPc55r8kw= =c9cO -----END PGP SIGNATURE----- --Apple-Mail=_6CBFD6B8-9F70-424E-80C8-8ED706EA8BCA--