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 > <bitcoin-dev@lists.linuxfoundation.org > <mailto:bitcoin-dev@lists.linuxfoundation.org>> 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 > <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 > _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
