Blockchain-based Secure Key Management model for High-speed Railway

Zikai Zhang, Jingyi Li, Yifei Sun, Yidong Li, Haifeng Song, Hairong Dong

Abstract: Key management is an essential component for providing security in high-speed railway wireless networks. However, due to a large number of trackside devices, the security and efficiency of wireless communications are hard to guarantee for the high-speed train with the real-time constraint of train control information transmission. In this article, we first propose a blockchain-based key management system for the high-speed railway with cloud computing to protect communication security, improve computing capability and meet the communication delay constraint. The proposed scheme consists of four main security mechanisms: a graph-based blockchain with blockchain slices to store public keys of entities, a two-layer key encryption authentication to defend against attacks, a pre-generated group encryption scheme to improve efficiency, and a new authentication method of the high-speed train to further improve the security. The performance simulations show that our scheme is superior to existing methods in terms of security and communication costs.