EP-SeaAKA: Enhanced Privacy-Preserving Quantum-Resistant Authentication and Key Agreement for RIS-assisted 6G Networks

The adoption of 6G networks introduces unprecedented security challenges that extend beyond the capabilities of current authentication protocols. EP-SeaAKA extends SeaAKA authentication for 6G networks by addressing critical vulnerabilities while maintaining backward compatibility. The protocol introduces three key innovations: (1) privacy-preservation using zero-knowledge proofs and homomorphic encryption, protecting identities during re-authentication while enabling service provisioning; (2) quantum-resistant primitives based on R-LWE problem with formal security reduction; (3) RIS-aware authentication leveraging synchronized reflection patterns as spatiotemporal factors. Security analysis provides R-LWE hardness reduction with parameters (<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">n</i> = 2048, <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">q</i> = 12289, σ = 3.2) and differential privacy guarantees (ϵ = 0.1, δ < 10<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−6</sup>). Performance evaluation shows EP-SeaAKA adds only 8.7% computational overhead during initialization while achieving 36% re-authentication latency reduction and maintaining strong scalability.