{"type":"rich","version":"1.0","author_name":"npub1m230cem2yh3mtdzkg32qhj73uytgkyg5ylxsu083n3tpjnajxx4qqa2np2","author_url":"https://nostr.ae/npub1m230cem2yh3mtdzkg32qhj73uytgkyg5ylxsu083n3tpjnajxx4qqa2np2","provider_name":"njump","provider_url":"https://nostr.ae","html":"📅 Original date posted:2015-12-19\n📝 Original message:At the recent Scaling Bitcoin conference in Hong Kong we had a chatham\nhouse rules workshop session attending by representitives of a super\nmajority of the Bitcoin hashing power.\n\nOne of the issues raised by the pools present was block withholding\nattacks, which they said are a real issue for them. In particular, pools\nare receiving legitimate threats by bad actors threatening to use block\nwithholding attacks against them. Pools offering their services to the\ngeneral public without anti-privacy Know-Your-Customer have little\ndefense against such attacks, which in turn is a threat to the\ndecentralization of hashing power: without pools only fairly large\nhashing power installations are profitable as variance is a very real\nbusiness expense. P2Pool is often brought up as a replacement for pools,\nbut it itself is still relatively vulnerable to block withholding, and\nin any case has many other vulnerabilities and technical issues that has\nprevented widespread adoption of P2Pool.\n\nFixing block withholding is relatively simple, but (so far) requires a\nSPV-visible hardfork. (Luke-Jr's two-stage target mechanism) We should\ndo this hard-fork in conjunction with any blocksize increase, which will\nhave the desirable side effect of clearly show consent by the entire\necosystem, SPV clients included.\n\n\nNote that Ittay Eyal and Emin Gun Sirer have argued(1) that block\nwitholding attacks are a good thing, as in their model they can be used\nby small pools against larger pools, disincentivising large pools.\nHowever this argument is academic and not applicable to the real world,\nas a much simpler defense against block withholding attacks is to use\nanti-privacy KYC and the legal system combined with the variety of\nwithholding detection mechanisms only practical for large pools.\nEqually, large hashing power installations - a dangerous thing for\ndecentralization - have no block withholding attack vulnerabilities.\n\n1) http://hackingdistributed.com/2014/12/03/the-miners-dilemma/\n\n-- \n'peter'[:-1]@petertodd.org\n00000000000000000188b6321da7feae60d74c7b0becbdab3b1a0bd57f10947d\n-------------- next part --------------\nA non-text attachment was scrubbed...\nName: signature.asc\nType: application/pgp-signature\nSize: 650 bytes\nDesc: Digital signature\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20151219/8c0d100a/attachment.sig\u003e"}