Smartphone Authentication Technology Enhancement for Advanced Smart Contract Application Security

Smartphone apps frequently use smart contracts which are based on blockchain sharded databases. The rapidly increasing cyber-attack rate is threatening the safety and security of smartphone users. In addition, Sybil attacks are commonly used in these cyber-attacks, which cause serious problems in smartphone authentication. To solve these problems, this paper proposes a Certificate based Trust Blockchain for Sharded Databases (CTBSD) scheme, which was designed to prevent Sybil nodes from having a dominant influence on blockchain systems through a trust-based shard clustering mechanism. The CTBSD scheme works with the Diameter authentication protocol, which is used in mobile smartphone networks. The authentication procedures of the Diameter digital certificates (which are based on unique information of each node) are combined with the blockchain consensus process of each shard. In this scheme, the trust authority (TA) collects trust information after the practical Byzantine fault tolerant (PBFT) consensus process, where honest nodes are assigned rewards and suspected Sybil nodes are assigned penalties with commit results. The simulation results show that the proposed scheme improves the security and scalability performance compared to existing schemes.