Zero trust-based authentication for Inter-Satellite Links in NextGen Low Earth Orbit networks

Next Generation (NextGen) Low Earth Orbit satellite networks are rapidly expanding to support global communication and 6G technology transition. This growth exposes networks to new security challenges due to wide coverage in hostile areas and increased access points in space and on Earth. Traditional static authentication methods prove inadequate in this dynamic environment. We address these challenges by developing a Zero Trust Authentication Protocol for Inter-Satellite Link (ISL) communication. Our protocol implements a novel verification process that leverages orbital signals to authenticate ISLs. This approach ensures secure data access and transmission exclusively among verified satellites, mitigating threats from eavesdropping, signal spoofing, impersonation, and replay attacks. To optimize security and resource efficiency, we integrate Hyperelliptic Curve Cryptography (HECC) into our protocol. We validate our approach through MATLAB and Systems Tool Kit (STK) simulations, complemented by BAN Logic and Scyther analyses. Our findings demonstrate that our protocol enhances the security framework of NextGen LEO networks without compromising their performance or operational capabilities. • Enables direct authentication and key agreement via ISLs using orbital vectors. • Supports adaptive, continuous security without full reliance on ground stations. • Aligns with key tenets of Zero Trust: – Continuous Authentication: Recalculates tokens to limit key exposure. – Multi-Factor Authentication: Uses orbital vectors and crypto keys. – Encryption Everywhere: HECC ensures 80-bit security with shorter keys. – Network Segmentation: Forms isolated ISL-based satellite domains. • Resists eavesdropping, spoofing, impersonation, replay, and MitM attacks. • Ensures mutual authentication, key secrecy, unforgeability, and anonymity. • Validated through formal verification and simulation: – Proved security using Scyther tool and BAN Logic analysis. – Simulated in MATLAB and STK to demonstrate practical feasibility. – Achieves 98.15% lower communication and 87.21% lower computation than existing schemes.