{"type":"rich","version":"1.0","title":"Antoine Riard [ARCHIVE] wrote","author_name":"Antoine Riard [ARCHIVE] (npub1vj…4x8dd)","author_url":"https://njump.me/npub1vjzmc45k8dgujppapp2ue20h3l9apnsntgv4c0ukncvv549q64gsz4x8dd","provider_name":"njump","provider_url":"https://njump.me","html":"📅 Original date posted:2020-05-13\n📝 Original message:Hi Chris,\n\nWhile approaching this question, I think you should consider economic\nweight of nodes in evaluating miner consensus-hijack success. Even if you\nexpect a disproportionate ratio of full-nodes-vs-SPV, they may not have the\nsame  economic weight at all, therefore even if miners are able to lure a\nmajority of SPV clients they may not be able to stir economic nodes. SPV\nclients users will now have an incentive to cancel their hijacked history\nto stay on the most economic meaningful chain. And it's already assumed,\nthat if you run a bitcoin business or LN routing node, you do want to run\nyour own full-node.\n\nI agree it may be hard to evaluate economic-weight-to-chain-backend\nsegments, specially with offchain you disentangle an onchain output value\nfrom its real payment traffic. To strengthen SPV, you may implement forks\ndetection and fallback to some backup node(s) which would serve as an\nauthoritative source to arbiter between branches. Such backup node(s) must\nbe picked up manually at client initialization, before any risk of conflict\nto avoid Reddit-style of hijack during contentious period or other massive\nsocial engineering. You don't want autopilot-style of recommendations for\npicking up a backup nodes and avoid cenralization of backups, but somehow a\nuniform distribution. A backup node may be a private one, it won't serve\nyou any data beyond headers, and therefore you preserve public nodes\nbandwidth, which IMO is the real bottleneck. I concede it won't work well\nif you have a ratio of 1000-SPV for 1-full-node and people are not\neffectively able to pickup a backup among their social environment.\n\nWhat do you think about this model ?\n\nCheers,\n\nAntoine\n\nLe mar. 12 mai 2020 à 17:06, Chris Belcher \u003cbelcher at riseup.net\u003e a écrit :\n\n\u003e On 05/05/2020 16:16, Lloyd Fournier via bitcoin-dev wrote:\n\u003e \u003e On Tue, May 5, 2020 at 9:01 PM Luke Dashjr via bitcoin-dev \u003c\n\u003e \u003e bitcoin-dev at lists.linuxfoundation.org\u003e wrote:\n\u003e \u003e\n\u003e \u003e\u003e On Tuesday 05 May 2020 10:17:37 Antoine Riard via bitcoin-dev wrote:\n\u003e \u003e\u003e\u003e Trust-minimization of Bitcoin security model has always relied first\n\u003e and\n\u003e \u003e\u003e\u003e above on running a full-node. This current paradigm may be shifted by\n\u003e LN\n\u003e \u003e\u003e\u003e where fast, affordable, confidential, censorship-resistant payment\n\u003e \u003e\u003e services\n\u003e \u003e\u003e\u003e may attract a lot of adoption without users running a full-node.\n\u003e \u003e\u003e\n\u003e \u003e\u003e No, it cannot be shifted. This would compromise Bitcoin itself, which\n\u003e for\n\u003e \u003e\u003e security depends on the assumption that a supermajority of the economy\n\u003e is\n\u003e \u003e\u003e verifying their incoming transactions using their own full node.\n\u003e \u003e\u003e\n\u003e \u003e\n\u003e \u003e Hi Luke,\n\u003e \u003e\n\u003e \u003e I have heard this claim made several times but have never understood the\n\u003e \u003e argument behind it. The question I always have is: If I get scammed by\n\u003e not\n\u003e \u003e verifying my incoming transactions properly how can this affect anyone\n\u003e \u003e else? It's very unintuative.  I've been scammed several times in my life\n\u003e in\n\u003e \u003e fiat currency transactions but as far as I could tell it never negatively\n\u003e \u003e affected the currency overall!\n\u003e \u003e\n\u003e \u003e The links you point and from what I've seen you say before refer to\n\u003e \"miner\n\u003e \u003e control\" as the culprit. My only thought is that this is because a light\n\u003e \u003e client could follow a dishonest majority of hash power chain. But this\n\u003e just\n\u003e \u003e brings me back to the question. If, instead of BTC, I get a payment in\n\u003e some\n\u003e \u003e miner scamcoin on their dishonest fork (but I think it's BTC because I'm\n\u003e \u003e running a light client) that still seems to only to damage me. Where does\n\u003e \u003e the side effect onto others on the network come from?\n\u003e \u003e\n\u003e \u003e Cheers,\n\u003e \u003e\n\u003e \u003e LL\n\u003e \u003e\n\u003e\n\u003e Hello Lloyd,\n\u003e\n\u003e The problem comes when a large part of the ecosystem gets scammed at\n\u003e once, which is how such an attack would happen in practice.\n\u003e\n\u003e For example, consider if bitcoin had 10000 users. 10 of them use a full\n\u003e node wallet while the other 9990 use an SPV wallet. If a miner attacked\n\u003e the system by printing infinite bitcoins and spending coins without a\n\u003e valid signature, then the 9990 SPV wallets would accept those fake coins\n\u003e as payment, and trade the coins amongst themselves. After a time those\n\u003e coins would likely be the ancestors of most active coins in the\n\u003e 9990-SPV-wallet ecosystem. Bitcoin would split into two currencies:\n\u003e full-node-coin and SPV-coin.\n\u003e\n\u003e Now the fraud miners may become well known, perhaps being published on\n\u003e bitcoin news portals, but the 9990-SPV-wallet ecosystem has a strong\n\u003e incentive to be against any rollback. Their recent transactions would\n\u003e disappear and they'd lose money. They would argue that they've already\n\u003e been using the coin for a while, and it works perfectly fine, and anyway\n\u003e a coin that can be spent in 9990 places is more useful than one that can\n\u003e be spent in just 10 places. The SPV-wallet community might even decide\n\u003e to use something like `invalidateblock` to make sure their SPV-coin\n\u003e doesn't get reorg'd out of existence. There'd also likely be a social\n\u003e attack, with every bitcoin community portal being flooded with bots and\n\u003e shills advocating the merits of SPV-coin. This is not a hypothetical\n\u003e because we already saw the same thing during the scalability conflict\n\u003e 2015-2017.\n\u003e\n\u003e Before you know it, \"Bitcoin\" would become SPV-coin with inflation and\n\u003e arbitrary seizure. Any normal user could download software called\n\u003e \"Bitcoin wallet\" which they trust and have used before, but instead of\n\u003e using Bitcoin they'd be using SPV-coin. You may be one of the 10 wallets\n\u003e backed by a full node, but that won't do much good to you when 9990\n\u003e users happily use another coin as their medium of exchange.\n\u003e\n\u003e Regards\n\u003e CB\n\u003e _______________________________________________\n\u003e Lightning-dev mailing list\n\u003e Lightning-dev at lists.linuxfoundation.org\n\u003e https://lists.linuxfoundation.org/mailman/listinfo/lightning-dev\n\u003e\n-------------- next part --------------\nAn HTML attachment was scrubbed...\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20200513/91739e5e/attachment.html\u003e"}