{"type":"rich","version":"1.0","author_name":"npub1g6vxlp4e0nyhs2dqxxcryztyf5f5hyuaq93nw4r87zcnv0sdsa0qqsl5wd","author_url":"https://nostr.ae/npub1g6vxlp4e0nyhs2dqxxcryztyf5f5hyuaq93nw4r87zcnv0sdsa0qqsl5wd","provider_name":"njump","provider_url":"https://nostr.ae","html":"📅 Original date posted:2016-05-10\n📝 Original message:The various chunks in the double SHA256 are\n\nChunk 1: 64 bytes\nversion\nprevious_block_digest\nmerkle_root[31:4]\n\nChunk 2: 64 bytes\nmerkle_root[3:0]\nnonce\ntimestamp\ntarget\n\nChunk 3: 64 bytes\ndigest from first sha pass\n\nTheir improvement requires that all data in Chunk 2 is identical except for\nthe nonce.  With 4 bytes, the birthday paradox means collisions can be\nfound reasonable easily.\n\nIf hard forks are allowed, then moving more of the merkle root into the 2nd\nchunk would make things harder.  The timestamp and target could be moved\ninto chunk 1.  This increases the merkle root to 12 bytes in the 2nd\nchunk.  Finding collisions would be made much more difficult.\n\nIf ASIC limitations mean that the nonce must stay where it is, this would\nmean that the merkle root would be split into two pieces.\n\nOn Tue, May 10, 2016 at 7:57 PM, Peter Todd via bitcoin-dev \u003c\nbitcoin-dev at lists.linuxfoundation.org\u003e wrote:\n\n\u003e As part of the hard-fork proposed in the HK agreement(1) we'd like to make\n\u003e the\n\u003e patented AsicBoost optimisation useless, and hopefully make further similar\n\u003e optimizations useless as well.\n\u003e\n\u003e What's the best way to do this? Ideally this would be SPV compatible, but\n\u003e if it\n\u003e requires changes from SPV clients that's ok too. Also the fix this should\n\u003e be\n\u003e compatible with existing mining hardware.\n\u003e\n\u003e\n\u003e 1)\n\u003e https://medium.com/@bitcoinroundtable/bitcoin-roundtable-consensus-266d475a61ff\n\u003e\n\u003e 2)\n\u003e http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-April/012596.html\n\u003e\n\u003e --\n\u003e https://petertodd.org 'peter'[:-1]@petertodd.org\n\u003e\n\u003e _______________________________________________\n\u003e bitcoin-dev mailing list\n\u003e bitcoin-dev at lists.linuxfoundation.org\n\u003e https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev\n\u003e\n\u003e\n-------------- next part --------------\nAn HTML attachment was scrubbed...\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20160510/cb6a2690/attachment.html\u003e"}