{"type":"rich","version":"1.0","title":"Nadav Ivgi [ARCHIVE] wrote","author_name":"Nadav Ivgi [ARCHIVE] (npub1f2…ydpll)","author_url":"https://yabu.me/npub1f2w9pm06c4k9ay8rst7757thahg2tfrtd0n645zxrtsqwhvaysrswydpll","provider_name":"njump","provider_url":"https://yabu.me","html":"📅 Original date posted:2022-04-25\n📝 Original message:darosior via bitcoin-dev wrote:\n\u003e i doubt CTV is necessary nor sufficient for this\n\nI would be interested to hear more on this.\n\nIs it not necessary because you can exchange and store pre-signed\ntransactions instead?\n\nWhat purpose is it not sufficient for? There are some vault designs out\nthere that are able to achieve interesting properties with CTV, like James\nO'Beirne's simple-ctv-vault:\n\nhttps://github.com/jamesob/simple-ctv-vault\n(the basic design expressed in Minsc:\nhttps://min.sc/nextc/#gist=001cf1fcb0e24ca9f3614c4db9bfe57d:4)\n\nOn Fri, Apr 22, 2022 at 2:23 PM darosior via bitcoin-dev \u003c\nbitcoin-dev at lists.linuxfoundation.org\u003e wrote:\n\n\u003e I would like to know people's sentiment about doing (a very slightly\n\u003e tweaked version of) BIP118 in place of\n\u003e (or before doing) BIP119.\n\u003e\n\u003e SIGHASH_ANYPREVOUT and its precedent iterations have been discussed for\n\u003e over 6 years. It presents proven and\n\u003e implemented usecases, that are demanded and (please someone correct me if\n\u003e i'm wrong) more widely accepted than\n\u003e CTV's.\n\u003e\n\u003e SIGHASH_ANYPREVOUTANYSCRIPT, if its \"ANYONECANPAY\" behaviour is made\n\u003e optional [0], can emulate CTV just fine.\n\u003e Sure then you can't have bare or Segwit v0 CTV, and it's a bit more\n\u003e expensive to use. But we can consider CTV\n\u003e an optimization of APO-AS covenants.\n\u003e\n\u003e CTV advocates have been presenting vaults as the flagship usecase.\n\u003e Although as someone who've been trying to\n\u003e implement practical vaults for the past 2 years i doubt CTV is necessary\n\u003e nor sufficient for this (but still\n\u003e useful!), using APO-AS covers it. And it's not a couple dozen more virtual\n\u003e bytes that are going to matter for\n\u003e a potential vault user.\n\u003e\n\u003e If after some time all of us who are currently dubious about CTV's stated\n\u003e usecases are proven wrong by onchain\n\u003e usage of a less efficient construction to achieve the same goal, we could\n\u003e roll-out CTV as an optimization.  In\n\u003e the meantime others will have been able to deploy new applications\n\u003e leveraging ANYPREVOUT (Eltoo, blind\n\u003e statechains, etc..[1]).\n\u003e\n\u003e\n\u003e Given the interest in, and demand for, both simple covenants and better\n\u003e offchain protocols it seems to me that\n\u003e BIP118 is a soft fork candidate that could benefit more (if not most of)\n\u003e Bitcoin users.\n\u003e Actually i'd also be interested in knowing if people would oppose the\n\u003e APO-AS part of BIP118, since it enables\n\u003e CTV's features, for the same reason they'd oppose BIP119.\n\u003e\n\u003e\n\u003e [0] That is, to not commit to the other inputs of the transaction (via\n\u003e `sha_sequences` and maybe also\n\u003e `sha_amounts`). Cf\n\u003e https://github.com/bitcoin/bips/blob/master/bip-0118.mediawiki#signature-message\n\u003e .\n\u003e\n\u003e [1] https://anyprevout.xyz/ \"Use Cases\" section\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-------------- next part --------------\nAn HTML attachment was scrubbed...\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20220425/cd6fa22e/attachment-0001.html\u003e"}