A Lightweight and Secure Authentication Protocol for Space-Ground Integrated Network of Railway

It is one of the important aspects of the future railway dedicated wireless communication system to realize the full wireless coverage when the train passes through different environments. Based on this observation, we introduce low Earth orbit (LEO) satellites into the Long Term Evolution for Railway (LTE-R) to construct a space-ground aggregated network architecture and propose a lightweight and secure authentication key agreement scheme. Specifically, the public key encryption is utilized to solve the problem of plaintext transmission in the standard protocol. Furthermore, the Elliptic Curve Cryptosystem (ECC) is used to design and realize the secure access authentication process of space network. Finally, the Chinese Remainder Theorem is introduced to realize the efficient handover authentication between heterogeneous networks and between different satellites. Security analysis and performance simulation show that the proposed scheme is superior to the existing schemes in terms of security, computation cost, and communication overhead.