Byzantine-resilient distributed consensus for autonomous satellite constellation via optical inter-satellite links

• First practical integration of Byzantine fault tolerance into satellite precision orbit control , achieving sub-10 m ground track accuracy despite 30% compromised nodes. • Novel thrust-level consensus mechanism directly votes on control inputs rather than state estimates, automatically compensating for heterogeneous satellite characteristics while suppressing malicious attacks. • Discovery of "consensus drag" phenomenon : moderate communication degradation (10% link loss) paradoxically improves tracking accuracy by 27% compared to full connectivity. • Monte Carlo validation (N=100 trials) demonstrates uniform robustness across Byzantine ratios with statistical stability (CV<20%, p=0.43) and >95% consensus success. Large-scale satellite constellations require autonomous distributed control to maintain precise orbital geometry while withstanding Byzantine faults, yet traditional centralized architectures fail beyond 50 satellites due to O ( N 3 ) complexity, single-point vulnerabilities, and communication delays. This paper introduces a Byzantine-resilient distributed thrust consensus framework integrating PBFT principles with high-fidelity optical inter-satellite link modeling for RGT-Walker constellations. The algorithm employs direct thrust-level consensus, where satellites vote on control inputs rather than state estimates, combined with three-layer validation (physics checks, GPS cross-verification, virtual partitioning) to suppress malicious proposals. Evaluation across seven scenarios (nominal, 10%/20%/30% Byzantine faults, 1%/5%/10% link loss) demonstrates uniform robustness: ground track errors below 10 m and consensus success >95% even at the PBFT limit (30% Byzantine ratio). Monte Carlo validation ( N =100 trials) confirms statistical stability (CV<20%, ANOVA p=0.43). High-fidelity optical ISL modeling reveals a counterintuitive "consensus drag" phenomenon where 10% link loss improves tracking accuracy by 27% compared to full connectivity. The algorithm achieves O ( N log N ) complexity, 73% fuel savings versus centralized control, and scales to 100+ satellites, establishing the first practical Byzantine fault tolerance for precision orbit control.