bridge: each node draws its own receiver noise - #23
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The chip model's noise seed was never set, so every native node ran the same receiver-noise stream from the same counter. That stream is what a node seeds its RNG from - fast_rng.begin(radio.getRngSeed()) reads it - so every node's CSMA backoff and advert jitter were correlated across the whole mesh, and any result that depends on two nodes not choosing the same slot was optimistic or pessimistic in a way nothing measured. The chip's noise seed now defaults to the node's identity seed, which the simulator already makes distinct per node, XORed so it is not literally the number the keypair is also derived from. --noise-seed overrides it for a caller that wants to set it directly. This is the native half of the per-node noise the emulated backend already had (MeshBench/meshbench#556). MeshBench/meshbench#720 Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01Q9HbD44EKWWTRYgxbFGxf6
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Every native node ran the chip model's noise stream from the same seed (0) and the same counter, so every node's
fast_rng(fast_rng.begin(radio.getRngSeed()), which reads the chip's random register) was seeded identically. CSMA backoff and advert jitter were correlated across the whole mesh (MeshBench/meshbench#720).The chip's noise seed now defaults to the node's identity seed - which the simulator already makes distinct per node via
--seed- XORed with a constant so it is not literally the number the keypair is derived from.--noise-seed Noverrides it. This is the native equivalent of the per-node noise the emulated chip got in MeshBench/meshbench#556 (vsx_set_noise_seed); the vendoredvirtual-sx1262already exposessetNoiseSeed, it was simply never called.Unknown args are ignored by the parser, so an older simulator that does not send
--noise-seedstill gets per-node noise from the identity-seed default.🤖 Generated with Claude Code
https://claude.ai/code/session_01Q9HbD44EKWWTRYgxbFGxf6