Artifact 464b82c888084e65fec7bea9864e4abaa8f68acaac73c13da4904d2e91876547:
The sync sweep proved convergence only once the network fully healed (every fault probability to zero), so a protocol that converges on a perfect wire but livelocks under sustained loss would still pass.
Phase 2b runs a fresh session over a wire held at a fixed drop/dup rate that is never healed, and asserts the same convergence and termination oracles within a window scaled from the loss rate: expected rounds are the clean window over (1 - p_loss) squared per direction, times a safety factor, recomputed in a comment rather than left a magic number. No corruption is injected -- a corrupted body is already a modeled lost round.
The protocol converges comfortably. Over 200 seeds the worst run took 7, 13, and 18 rounds at 10, 25, and 40 percent loss, against windows of 160, 228, and 356 -- no livelock surfaced. The gate joins at 10 percent so it stays fast and deterministic; the deeper soak sweeps the wider rate set. Pinning the window below the real convergence need trips the liveness oracle, so the check is not vacuous.
The liveness-under-faults discipline follows TigerBeetle's VOPR. by dmestas on 2026-07-20 04:37:48.
C Prove\ssync\sliveness\sunder\sa\sdegraded,\snever-healed\swire\n\nThe\ssync\ssweep\sproved\sconvergence\sonly\sonce\sthe\snetwork\sfully\shealed\n(every\sfault\sprobability\sto\szero),\sso\sa\sprotocol\sthat\sconverges\son\sa\nperfect\swire\sbut\slivelocks\sunder\ssustained\sloss\swould\sstill\spass.\n\nPhase\s2b\sruns\sa\sfresh\ssession\sover\sa\swire\sheld\sat\sa\sfixed\sdrop/dup\srate\nthat\sis\snever\shealed,\sand\sasserts\sthe\ssame\sconvergence\sand\stermination\noracles\swithin\sa\swindow\sscaled\sfrom\sthe\sloss\srate:\sexpected\srounds\sare\nthe\sclean\swindow\sover\s(1\s-\sp_loss)\ssquared\sper\sdirection,\stimes\sa\nsafety\sfactor,\srecomputed\sin\sa\scomment\srather\sthan\sleft\sa\smagic\snumber.\nNo\scorruption\sis\sinjected\s--\sa\scorrupted\sbody\sis\salready\sa\smodeled\slost\nround.\n\nThe\sprotocol\sconverges\scomfortably.\sOver\s200\sseeds\sthe\sworst\srun\stook\n7,\s13,\sand\s18\srounds\sat\s10,\s25,\sand\s40\spercent\sloss,\sagainst\swindows\sof\n160,\s228,\sand\s356\s--\sno\slivelock\ssurfaced.\sThe\sgate\sjoins\sat\s10\spercent\nso\sit\sstays\sfast\sand\sdeterministic;\sthe\sdeeper\ssoak\ssweeps\sthe\swider\nrate\sset.\sPinning\sthe\swindow\sbelow\sthe\sreal\sconvergence\sneed\strips\sthe\nliveness\soracle,\sso\sthe\scheck\sis\snot\svacuous.\n\nThe\sliveness-under-faults\sdiscipline\sfollows\sTigerBeetle's\sVOPR.\n 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