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 A946F256 for ; Tue, 10 May 2016 22:59:56 +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 03E09A6 for ; Tue, 10 May 2016 22:59:55 +0000 (UTC) Received: from [172.17.0.2] (gw.vpn.bluematt.me [162.243.132.6]) by mail.bluematt.me (Postfix) with ESMTPSA id 757C85FFC3; Tue, 10 May 2016 22:59:54 +0000 (UTC) To: Sergio Demian Lerner , Bitcoin Protocol Discussion , Tier Nolan References: <20160510185728.GA1149@fedora-21-dvm> From: Matt Corallo Message-ID: <573267E8.9050209@mattcorallo.com> Date: Tue, 10 May 2016 22:59:52 +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: 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 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 10 May 2016 22:59:56 -0000 Replies inline. On 05/10/16 21:43, Sergio Demian Lerner via bitcoin-dev wrote: -snip- > But some ASIC companies already have cores that are better (on power, > cost, rate, temperature, etc.) than competing companies ASICs. Why do > you think a 10% improvement from AsicBoost is different from many of > other improvements they already have (secretly) added? Maybe we (?) > should only allow ASICs that have a 100% open source designs? One is patented and requires paying a license fee to a group, or more likely, ends up with it being impossible to import hardware from other jurisdictions into the US/western world. The other requires more investment in R&D, and over the long run, there is no guaranteed advantage to such groups. > If we change the protocol then the message to the ecosystem is that ASIC > optimizations should be kept secret. To some extent, this is the case, but there is a strong difference between a guaranteed advantage enforced by the legal system and one that is true due to intellectual superiority. In the long run, I am confident the second will not remain the case. For example, AsicBoost was independently discovered by at least two companies/individuals within a year or two. > It is fair to change the protocol > because we don't like that certain ASIC manufacturer has better chips, > if the chips are sold in the market and anyone can buy them? And what > about using approximate adders (30% improvement), or dual rail > asynchronous adders (also more than 10% improvement) ? How do we repair > those? As far as I'm aware neither of these are patented. Is this not the case? > Disclaimer: I have stake in AsicBoost, but I'm not sure about this. > > > On Tue, May 10, 2016 at 5:27 PM, 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 > > 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 > > > _______________________________________________ > bitcoin-dev mailing list > 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 > > > > > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev >