{"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:2019-11-24\n📝 Original message:\nGood morning Bastien,\n\n\u003e While I agree with most of your points, I think there are subtleties to explore before\n\u003e completely rejecting the idea.\n\u003e\n\u003e \u003e every use of proof-of-work today (other than to power Bitcoin itself, as Bitcoin cannot support itself) can instead be done by using Bitcoins to impose this economic cost.\n\u003e\n\u003e That is philosophically true, but the complexity of integrating that small PoW into Lightning \n\u003e is much lower than the complexity of integrating *fair, un-gameable* upfront payments.\n\u003e And not all PoW is born equal: there are a lot of PoW schemes that have different trade-offs\n\u003e than Bitcoin mining (think ASIC-resistance such as variants of Cuckoo Cycle).\n\u003e\n\u003e Another key point is that creating ASICs for this PoW is fundamentally different from creating\n\u003e ASICs for mining a crypto-currency. Solving this PoW doesn't earn you any money: it merely\n\u003e allows you to spam to temporarily disrupt the network.\n\u003e Since this PoW isn't used in any consensus, we can change the spam PoW algorithm anytime\n\u003e we want, making all previous ASICs obsolete.\n\u003e So it's not obvious to me that anyone would find it viable to invest in creating such ASICs.\n\nhttps://github.com/libbitcoin/libbitcoin-system/wiki/Proof-of-Work-Fallacy\n\nWhile it is true that we do not need consensus at the Lightning layer, we still require that senders are compatible with intermediate nodes to the extent that they use intermediate nodes.\nThus a PoW change here would require that intermediate nodes reject older PoW (that is the entire point) while senders must be prepared to provide either the old PoW algorithm or the new one (as arbitrary intermediate nodes may not update immediately).\n\nSpecialization will arise to the extent that we design the system to allow it.\nIn this case, specialized PoW-providers will be paid in order to provide PoW that will be presented to intermediate nodes.\nFar better to just pay intermediate nodes directly and remove this additional friction.\n\n\n\u003e\n\u003e \u003e As hardware specialization for the specific Lightning-Network-proof-of-work arises, we will find that to practically limit spam, intermediate nodes will have to increase and increase the threshold for accepting proof-of-work, as spammers are going to switch to the more-specialized hardware.\n\u003e\n\u003e That's where I think it can be more subtle than what you describe (I may be wrong though as\n\u003e predicting future behavior is hard).\n\u003e\n\u003e Since I'm ruling out ASICs, we're only dealing with \"normal\" hardware bottlenecks (cpu/ram).\n\u003e That means attackers are not playing at a completely different scale than normal users.\n\nHow many botnets does a normal user control?\n\n\u003e The cost for attackers to generate an amount of spam mimicking N normal users will then be\n\u003e somewhat linear in N (to be investigated further). \n\u003e That's exactly the same result as upfront payments, where an attacker can still spam like\n\u003e he's N users if he's ready to pay a cost linear in N.\n\nThen just use upfront payments.\n\n\n\u003e \u003e requiring a fee is equivalent to requiring proof-of-work, incentive-wise.\n\u003e\n\u003e Not necessarily, given that\n\u003e 1) there is a finite bitcoin supply but an eventually infinite PoW\n\u003e supply (relevant in the unlikely case fees are burned)\n\u003e 2) sats are transferrable, whereas PoW isn't (relevant in the case fees\n\u003e are paid)\n\nNot actually.\nAgain, let me point out that PoW can be *bought*, that is precisely what Bitcoin blockchain layer does.\nAnd the blockchain layer PoW is bought with two things: fees and subsidies (inflation).\nThus PoW, being purchaseable, is incentive-wise equivalent to paying somebody to spend electricity (possibly with efficiencies at scale).\nJust cut the middleman.\n\nRegards,\nZmnSCPxj"}