{"type":"rich","version":"1.0","author_name":"npub17w8rw3wtcr03zdsdjhmcj37w0g6l79gsspleltsznexdktv0qw0qd3nc05","author_url":"https://nostr.ae/npub17w8rw3wtcr03zdsdjhmcj37w0g6l79gsspleltsznexdktv0qw0qd3nc05","provider_name":"njump","provider_url":"https://nostr.ae","html":"📅 Original date posted:2017-04-07\n📝 Original message:Hey everyone, This is an idea that I had about Segwit and Gregory's\nproposal from yesterday that I wanted to run by everyone on this list. I'm\nnot at all sure what this would mean for non-upgraded nodes on the network\nand would like feedback on that. This is not a formal BIP as it's a\nmodification to a previously submitted one, but I'm happy to formalize it\nif it would help.\n----------------------------------------\nMotivationOne of the interesting aspects of Gregory Maxwell’s proposal is\nthat it only precludes the covert version of ASICBoost. He specifically\nleft the overt version alone.\n\nOvert ASICBoost requires grinding on the version bits of the Block header\ninstead of the Merkle Root. This is likely more efficient than the Merkle\nRoot grinding (aka covert ASICBoost) and requires way less resources (much\nless RAM, SHA256 calculations, no tx shuffling, etc).\n\nIf we combine Gregory Maxwell’s proposal with BIP-141 (Segwit) and add a\nslight modification, this should, in theory, make ASICBoost a lot more\nuseful to miners and appeal to their financial interests.\nThe Modification\n\nCurrently, the version bits (currently 4 bytes, or 32 bits) in the header\nare used for BIP9 signaling. We change the version bits to a nonce-space so\nthe miners can use it for overt ASICBoost. The 32-bits are now moved over\nto the Coinbase transaction as part of the witness commitment. The witness\ncommitment goes from 38 bytes to 42 bytes, with the last 4 bytes being used\nas the version bits in the block header previously. The witness commitment\nbecomes required as per Gregory Maxwell’s proposal.\nReasoning\n\nFirst, this brings ASICBoost out into the open. Covert ASICBoost becomes\nmuch more costly and overt ASICBoost is now encouraged.\n\nSecond, we can make this change relatively quickly. Most of the Segwit\ntesting stays valid and this change can be deployed relatively quickly.\n\nNote on SPV clients\n\nCurrently Segwit stores the witness commitment in the Coinbase tx, so\nlightweight clients will need to get the Coinbase tx + Merkle proof to\nvalidate segwit transactions anyway. Putting block version information in\nthe Coinbase tx will not impose an extra burden on upgraded light clients.\n-------------- next part --------------\nAn HTML attachment was scrubbed...\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20170407/93c88127/attachment.html\u003e"}