{"type":"rich","version":"1.0","author_name":"npub16dt55fpq3a8r6zpphd9xngxr46zzqs75gna9cj5vf8pknyv2d7equx4wrd","author_url":"https://nostr.ae/npub16dt55fpq3a8r6zpphd9xngxr46zzqs75gna9cj5vf8pknyv2d7equx4wrd","provider_name":"njump","provider_url":"https://nostr.ae","html":"📅 Original date posted:2018-06-02\n📝 Original message:On Fri, Jun 01, 2018 at 07:02:38PM -0700, Jim Posen via bitcoin-dev wrote:\n\u003e Without the ability to verify filter validity, a client would have to stop\n\u003e syncing altogether in the presence of just one malicious peer, which is\n\u003e unacceptable.\n\nI'm confused about why this would be the case.  If Alice's node\ngenerates filters accurately and Mallory's node generates filters\ninaccurately, and they both send their filters to Bob, won't Bob be able\nto download any blocks either filter indicates are relevant to his\nwallet?\n\nIf Bob downloads a block that contains one of his transactions based on\nAlice's filter indicating a possible match at a time when Mallory's\nfilter said there was no match, then this false negative is perfect\nevidence of deceit on Mallory's part[1] and Bob can ban her.\n\nIf Bob downloads a block that doesn't contain any of his transactions\nbased on Mallory's filter indicating a match at a time when Alice's\nfilter said there was no match, then this false positive can be recorded\nand Bob can eventually ban Mallory should the false positive rate\nexceeds some threshold.\n\nUntil Mallory is eventually banned, it seems to me that the worst she\ncan do is waste Bob's bandwidth and that of any nodes serving him\naccurate information, such as Alice's filters and the blocks Bob\nis misled into downloading to check for matches.  The amount of\nattacker:defender asymetry in the bandwidth wasted increases if\nMallory's filters become less accurate, but this also increases her\nfalse positive rate and reduces the number of filters that need to be\nseen before Bob bans her, so it seems to me (possibly naively) that this\nis not a significant DoS vector.\n\n-Dave\n\n[1] Per BIP158 saying, \"a Golomb-coded set (GCS), which matches all\nitems in the set with probability 1\"\n-------------- next part --------------\nA non-text attachment was scrubbed...\nName: signature.asc\nType: application/pgp-signature\nSize: 833 bytes\nDesc: not available\nURL: \u003chttp://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20180602/9556f60f/attachment.sig\u003e"}