From adam at cypherspace.org Tue Jul 7 19:59:28 2015 From: adam at cypherspace.org (Adam Back) Date: Tue, 7 Jul 2015 21:59:28 +0200 Subject: [Lightning-dev] HTLCs using OP_CHECKSEQUENCEVERIFY/OP_LOCKTIMEVERIFY and revocation hashes. In-Reply-To: <1436298714.4352.55.camel@hppg6.kloosterkade> References: <87fv51eqjl.fsf@rustcorp.com.au> <1436298714.4352.55.camel@hppg6.kloosterkade> Message-ID: The use of the private key sending function, is just intended to be a more compact and efficient way of sending the other end of the channel a signed message, it says "well here, have the private key, you can sign it yourself". Now that being the case, and as the transaction has another signature anyway it occurred to me that you should be able to use a chain of hash preimages to do it more efficiently again. Rusty generalised that to have a lower setup by using a short of hypercube multi-dimensional array of preimages. (If you want 1million hash preimages, then you have to actually compute 1 million of them at setup.) I had the idea that Rusty might've written a blog post on this preimage generalisation however I dont seem to be able to find it now. Adam On 7 July 2015 at 21:51, CJP wrote: >> Since we use "revocation preimages" to revoke transactions (rather than >> sending pubkeys as the original draft paper) > > I remember the original paper mentioned sending private keys. I suppose > you mean that the preimages replace the *private* keys, not the pubkeys? > > I was not aware of that design change, but it sounds like an > improvement. > > CJP > > > _______________________________________________ > Lightning-dev mailing list > Lightning-dev at lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/lightning-dev