From ben at mord.io Tue Jan 30 16:26:36 2018 From: ben at mord.io (Benjamin Mord) Date: Tue, 30 Jan 2018 11:26:36 -0500 Subject: [Lightning-dev] lightning operation during / following a chain fork (e.g. BIP 50) In-Reply-To: <6Q40l0m3BQ68EQcQ26nDVz-NeQcA-ycp5N-GdO6CPCcWkESMR-ZRM86365AgRwBEieRrAzgDX8-cTfSkWxYP9RqGP6zxoWNn0naEAAD0iUo=@protonmail.com> References: <6Q40l0m3BQ68EQcQ26nDVz-NeQcA-ycp5N-GdO6CPCcWkESMR-ZRM86365AgRwBEieRrAzgDX8-cTfSkWxYP9RqGP6zxoWNn0naEAAD0iUo=@protonmail.com> Message-ID: Thank you, ZmnSCPxj. BCH is a warmup question for several reasons, I believe they don't even support segwit (!) so lightning would be unsafe due to their txid mutability bug. I agree altcoin support should be lower priority, whenever it is obvious which is the altcoin (as indeed, is abundantly clear wrt BTC vs BCH). But it might one day become unclear. I remain concerned about safety despite BIP 50 scenarios, forks with more legitimate contention than so far seen, and also system stability in face of increasingly unsophisticated / gullible user base. As a cryptocurrency is little more than a trustless consensus mechanism, it seems circular to assume consensus in its design, especially if there are entities financially motivated to fracture that consensus. Resilience against forks would seem core to safety. If I think of a concrete solution, I'll send it first to this list for discussion - as I believe that is the preferred process? Thanks, Ben On Tue, Jan 30, 2018 at 1:16 AM, ZmnSCPxj wrote: > Good morning Ben, > > Hi, > > One topic I can't seem to find in the BOLTs is how lightning nodes > maintain consensus during or after a fork of the underlying blockchain(s). > For example, channel_announcement messages use a chain_hash, defined as > hash of underlying block chain's genesis block, to identify the currency in > use. Today, one might ask which hash identifies BTC as opposed to BCH? > > > I believe the rough consensus among most Lightning developers is that BTC > is "the real BTC" and gets the Satoshi genesis hash, while BCH is an > altcoin that was forked off BTC and gets as hash the branching-off point. > You could try to convince people developing and using Lightning software to > do the reverse, but I think it is unlikely that many people would agree to > that. > > > A more difficult question arises in how existing channels handle > intentional forks which arise after funding of a payment channel. > > An even more difficult question arises in the handling of unintentional > forks, as documented for example in BIP 50. > > Have these scenarios been analyzed / designed yet, or does that work > remain? > > > The work remains. For the most part, the priority is to get > implementations to a state, where we can safely deploy on Bitcoin Mainnet. > Then optimize further by adding RBF and multi-channel funding, then > integrate Burchert-Decker-Wattenhofer channel factories, splicing, and so > on. Greater support for altcoins can be done later. > > For forked altcoins, short channel IDs contain the block height at which > the funding transaction confirmed. This might be used to judge if a > channel contains forked coins or not. > > Regards, > ZmnSCPxj > > > Thanks! > Ben > > > -------------- next part -------------- An HTML attachment was scrubbed... URL: