From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 1600193D for ; Fri, 21 Aug 2015 05:55:43 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from outmail148108.authsmtp.net (outmail148108.authsmtp.net [62.13.148.108]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 2C6DEAB for ; Fri, 21 Aug 2015 05:55:41 +0000 (UTC) Received: from mail-c235.authsmtp.com (mail-c235.authsmtp.com [62.13.128.235]) by punt15.authsmtp.com (8.14.2/8.14.2/) with ESMTP id t7L5te0G022747; Fri, 21 Aug 2015 06:55:40 +0100 (BST) Received: from muck ([24.114.27.112]) (authenticated bits=128) by mail.authsmtp.com (8.14.2/8.14.2/) with ESMTP id t7L5tZcY048826 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Fri, 21 Aug 2015 06:55:38 +0100 (BST) Date: Thu, 20 Aug 2015 22:55:35 -0700 From: Peter Todd To: Jeff Garzik Message-ID: <20150821055534.GA27259@muck> References: <55D6AD19.10305@mattcorallo.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="YZ5djTAD1cGYuMQK" Content-Disposition: inline In-Reply-To: X-Server-Quench: 4092aa3a-47c9-11e5-b398-002590a15da7 X-AuthReport-Spam: If SPAM / abuse - report it at: http://www.authsmtp.com/abuse X-AuthRoute: OCd2Yg0TA1ZNQRgX IjsJECJaVQIpKltL GxAVKBZePFsRUQkR aQdMdAMUGUATAgsB AmMbW1JeVVh7XWM7 aQ5PbARZfEhJQQRr UldMSlVNFUssBmAE QnRNOxl2fw1EfjBx ZEFiXT5fXE14JBd+ E1NQEj4PeGZhPWUC AkNRfx5UcAFPdx8U a1UrBXRDAzANdhEy HhM4ODE3eDlSNhEd eAwTLEkTXUcNEXYa YDwvKh8LOmogFW0L NRs+LUUREA47E31a X-Authentic-SMTP: 61633532353630.1023:706 X-AuthFastPath: 0 (Was 255) X-AuthSMTP-Origin: 24.114.27.112/587 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 development mailing list Subject: Re: [bitcoin-dev] Revisiting NODE_BLOOM: Proposed BIP X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 21 Aug 2015 05:55:43 -0000 --YZ5djTAD1cGYuMQK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Aug 21, 2015 at 01:48:23AM -0400, Jeff Garzik via bitcoin-dev wrote: > If this is widely deployed + enabled, what is the impact to current walle= ts > in use? See my comment on the recently-opened issue, reproduced below. In short, not all that much, especially if we adopt my suggestion of having the Core implementation accept and respond to bloom filter requests from non-upgraded clients regardless of whether or not NODE_BLOOM was set until some fixed upgrade deadline in the future. Note that since the last time NODE_BLOOM was proposed, the landcape for (lite-)SPV clients has changed significantly in a few key ways: 1) @mikehearn's [Cartographer](https://github.com/mikehearn/httpseed) seed protocol has been created and deployed in production to allow (lite-)SPV clients to find nodes supporting arbitrary service bits, notable NODE_GETUTXOs. 2) Bloom filter usage has declined significantly, as lite-SPV clients are moving towards using centralized, trusted, servers run by the wallet authors. For instance [Mycelium](https://github.com/mycelium-com/wallet), [GreenBits](https://github.com/greenaddress/GreenBits), [AirBitz](https://www.reddit.com/r/Bitcoin/comments/3etohn/whats_wrong_= with_breadwallet/ctirou5), and [Electrum](https://electrum.org/#home) all fall in this category. 3) Bloom filters [have been found](http://eprint.iacr.org/2014/763) to have severe privacy issues, offering essentially no privacy at all. Under many threat models a small number of trusted servers pose less privacy security risk than connecting to random, sybil-attackable, peers using unencrypted connections and giving those peers very accurate wallet contents information. 4) Finally, Bloom filters still have [unsolved DoS attack issues](https://www.reddit.com/r/Bitcoin/comments/3hjak7/the_hard_work_= of_core_devs_not_xt_makes_bitcoin/cu9xntf?context=3D3), that will get significantly worse under upcoming blocksize increase proposals. Re: service bit identifier, I'd just pick 1<<3 -https://github.com/bitcoin/bitcoin/issues/6578#issuecomment-133226943 --=20 'peter'[:-1]@petertodd.org 00000000000000000402fe6fb9ad613c93e12bddfc6ec02a2bd92f002050594d --YZ5djTAD1cGYuMQK Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- iQGrBAEBCACVBQJV1r1TXhSAAAAAABUAQGJsb2NraGFzaEBiaXRjb2luLm9yZzAw MDAwMDAwMDAwMDAwMDAwNDAyZmU2ZmI5YWQ2MTNjOTNlMTJiZGRmYzZlYzAyYTJi ZDkyZjAwMjA1MDU5NGQvFIAAAAAAFQARcGthLWFkZHJlc3NAZ251cGcub3JncGV0 ZUBwZXRlcnRvZC5vcmcACgkQwIXyHOf0udz6OggAgCqBCV/JdgOrUr+d3XxIgZtI mbVUHtOkY4uF+azrHq5kJGLlZU/lOahGeknitrYETlBgSsp2BS+ySGIanZNWBm1b t3UId3Aoml8K34X/X5aSUAFC7QrlCTvgpjUneRXLlI/yo0yH4jB0lrltGvjxSCcU KHDl6QEXmk0FjVpENAfYso/qbT5KDj1RxXquF68Xi52kUAfl/+krCnXQuW6J1HKb /oRUhUYBE19N/3Og81CLTIh8ak+msNdelZNxYx8uBQOGXdfAFNpd4Trs69TtHke5 0haFv1Xtdpm11DirQyJwrjrdHyFlcWxM6c6sBQtFTu+caDgljasRvm6pcrg/xg== =fqER -----END PGP SIGNATURE----- --YZ5djTAD1cGYuMQK--