{"type":"rich","version":"1.0","title":"ZmnSCPxj [ARCHIVE] wrote","author_name":"ZmnSCPxj [ARCHIVE] (npub1g5…3ms3l)","author_url":"https://yabu.me/npub1g5zswf6y48f7fy90jf3tlcuwdmjn8znhzaa4vkmtxaeskca8hpss23ms3l","provider_name":"njump","provider_url":"https://yabu.me","html":"📅 Original date posted:2021-10-08\n📝 Original message:\nGood morning aj,\n\n\u003e     In order to transition from BOLT#3 format to this proposal, an onchain\n\u003e     transaction is required, as the \"revocable signatures\" arrangement cannot\n\u003e     be mimicked via the existing 2-of-2 CHECKMULTISIG output.\n\nA transaction is required, but I believe it is not necessary to put it *onchain* (at the cost of implementation complexity in the drop-onchain case).\n\nAn existing channel can \"simply\" sign a transitioning transaction from the current BOLT3 to your new scheme, and then invalidate the last valid commitment transactions (i.e. exchange revocation secrets) in the BOLT3 scheme.\nThe transitioning transaction can simply be kept offchain and its output used as the funding outpoint of all \"internal\" (to the two counterparties directly in the channel) states.\n\nThis general idea would work for all transitions *from* Poon-Dryja, I believe.\nIt may be possible with Decker-Russell-Osuntokun I think (give the transitioning transaction the next sequence `nLockTime` number), but the `SIGHASH_NOINPUT`ness and (maybe?) the `CSV` infects the mechanism being transitioned to, so this technique may be too complicated for transitioning *from* Decker-Russell-Osuntokun to some hypothetical future offchain updatable cryptocurrency system that does not need (or want) `SIGHASH_NOINPUT`.\n\nThis has the advantage of maintaining the historical longevity of the channel.\nMany pathfinding and autopilot heuristics use channel lifetime as a positive indicator of desirability, thus an *onchain* transitioning transaction is undesirable as that marks a closure of the previous channel.\nAnd the exact scheme of channels between forwarding nodes are not particularly the business of anyone else anyway.\n\n\nRegards,\nZmnSCPxj"}