A Blockchain-based Lightweight Privacy-Preserving Authentication Protocol for Access and Handover in Space-Ground Integrated Networks

Space-Ground Integrated Network (SGIN) aims to provide global broadband, especially in underserved areas. However, existing authentication schemes face challenges like high computational overhead, reliance on Network Control Centers (NCCs), user identity leakage, and repetitive authentication. We propose a lightweight, blockchain-based privacy-preserving authentication protocol using chameleon hash functions for mutual authentication between users and LEO satellites. This reduces computational overhead and reliance on NCCs. Blockchain establishes trust among satellites, enabling seamless handovers through information exchange. Security and performance analysis confirm the feasibility of the proposed scheme.