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| author | Matt Corallo <lf-lists@mattcorallo.com> | 2016-05-10 21:35:39 +0000 |
|---|---|---|
| committer | bitcoindev <bitcoindev@gnusha.org> | 2016-05-10 21:35:44 +0000 |
| commit | c52ab7b3aacfddc3b91d7d88c360e8e2f5b6fbea (patch) | |
| tree | a1692f05ab9968840b5a650eadfc5cd904073d45 | |
| parent | b42b27b85e705bb27b51811848a4752cc9877ee7 (diff) | |
| download | pi-bitcoindev-c52ab7b3aacfddc3b91d7d88c360e8e2f5b6fbea.tar.gz pi-bitcoindev-c52ab7b3aacfddc3b91d7d88c360e8e2f5b6fbea.zip | |
Re: [bitcoin-dev] Making AsicBoost irrelevant
| -rw-r--r-- | c9/85513770f61563bbf3bef4cc244d24da2b0e73 | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/c9/85513770f61563bbf3bef4cc244d24da2b0e73 b/c9/85513770f61563bbf3bef4cc244d24da2b0e73 new file mode 100644 index 000000000..28280218a --- /dev/null +++ b/c9/85513770f61563bbf3bef4cc244d24da2b0e73 @@ -0,0 +1,131 @@ +Return-Path: <lf-lists@mattcorallo.com> +Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org + [172.17.192.35]) + by mail.linuxfoundation.org (Postfix) with ESMTPS id 240E7721 + for <bitcoin-dev@lists.linuxfoundation.org>; + Tue, 10 May 2016 21:35:44 +0000 (UTC) +X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 +Received: from mail.bluematt.me (mail.bluematt.me [192.241.179.72]) + by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 7B94C137 + for <bitcoin-dev@lists.linuxfoundation.org>; + Tue, 10 May 2016 21:35:43 +0000 (UTC) +Received: from [172.17.0.2] (gw.vpn.bluematt.me [162.243.132.6]) + by mail.bluematt.me (Postfix) with ESMTPSA id 860135FFBD; + Tue, 10 May 2016 21:35:41 +0000 (UTC) +To: Tier Nolan <tier.nolan@gmail.com>, + Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org> +References: <20160510185728.GA1149@fedora-21-dvm> + <CAE-z3OWvLqONwaN+608jBn9=q1yUvU4ggGrMpA8rE6qmjDQHtg@mail.gmail.com> +From: Matt Corallo <lf-lists@mattcorallo.com> +Message-ID: <5732542B.20000@mattcorallo.com> +Date: Tue, 10 May 2016 21:35:39 +0000 +User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 + Thunderbird/38.7.0 +MIME-Version: 1.0 +In-Reply-To: <CAE-z3OWvLqONwaN+608jBn9=q1yUvU4ggGrMpA8rE6qmjDQHtg@mail.gmail.com> +Content-Type: text/plain; charset=windows-1252 +Content-Transfer-Encoding: 7bit +X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham + version=3.3.1 +X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on + smtp1.linux-foundation.org +Subject: Re: [bitcoin-dev] Making AsicBoost irrelevant +X-BeenThere: bitcoin-dev@lists.linuxfoundation.org +X-Mailman-Version: 2.1.12 +Precedence: list +List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org> +List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>, + <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe> +List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/> +List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org> +List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help> +List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>, + <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe> +X-List-Received-Date: Tue, 10 May 2016 21:35:44 -0000 + +Yea, I think in any hardfork that we should be talking about, a part of +it should include 1) fix the version field so its a static constant, 2) +the merkle root becomes hash of the real block header 3) swap first 2 +bytes of the merkle root with the timestamp's two high-order bits, 4) +swap the next 4 bytes of the merkle root with the difficulty field. + +I believe this should be compatible with all existing ASICs, with the +exception, possibly, of some 21 Inc hardware. I believe this fixes +AsicBoost (without thinking about it tooo much, so please critique). + +While this is somewhat nasty, the risks of AsicBoost and the precedent +that should be set necessitates a response, and it should be included in +any hardfork. + +Matt + +On 05/10/16 20:27, Tier Nolan via bitcoin-dev wrote: +> The various chunks in the double SHA256 are +> +> Chunk 1: 64 bytes +> version +> previous_block_digest +> merkle_root[31:4] +> +> Chunk 2: 64 bytes +> merkle_root[3:0] +> nonce +> timestamp +> target +> +> Chunk 3: 64 bytes +> digest from first sha pass +> +> Their improvement requires that all data in Chunk 2 is identical except +> for the nonce. With 4 bytes, the birthday paradox means collisions can +> be found reasonable easily. +> +> If hard forks are allowed, then moving more of the merkle root into the +> 2nd chunk would make things harder. The timestamp and target could be +> moved into chunk 1. This increases the merkle root to 12 bytes in the +> 2nd chunk. Finding collisions would be made much more difficult. +> +> If ASIC limitations mean that the nonce must stay where it is, this +> would mean that the merkle root would be split into two pieces. +> +> On Tue, May 10, 2016 at 7:57 PM, Peter Todd via bitcoin-dev +> <bitcoin-dev@lists.linuxfoundation.org +> <mailto:bitcoin-dev@lists.linuxfoundation.org>> wrote: +> +> As part of the hard-fork proposed in the HK agreement(1) we'd like +> to make the +> patented AsicBoost optimisation useless, and hopefully make further +> similar +> optimizations useless as well. +> +> What's the best way to do this? Ideally this would be SPV +> compatible, but if it +> requires changes from SPV clients that's ok too. Also the fix this +> should be +> compatible with existing mining hardware. +> +> +> 1) +> https://medium.com/@bitcoinroundtable/bitcoin-roundtable-consensus-266d475a61ff +> +> 2) +> http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-April/012596.html +> +> -- +> https://petertodd.org 'peter'[:-1]@petertodd.org <http://petertodd.org> +> +> _______________________________________________ +> bitcoin-dev mailing list +> bitcoin-dev@lists.linuxfoundation.org +> <mailto:bitcoin-dev@lists.linuxfoundation.org> +> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev +> +> +> +> +> _______________________________________________ +> bitcoin-dev mailing list +> bitcoin-dev@lists.linuxfoundation.org +> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev +> + |