Formal verification of secondary authentication protocol for 5G secondary authentication

The Fifth-Generation mobile network (5G) will enable interconnectivity between the Home Network (HN) and Data Network (DN) whereby mobile users with their User Equipment (UE) will be able to access services provided by external Service Providers (SP) seamlessly. The mobile user and SP will rely on security assurances provided by authentication protocols used. For 5G, primary authentication between the UE and the HN has been defined and specified by the Third Generation Partnership Project (3GPP) while the secondary authentication has also been defined but not specified. 3GPP recommends the Extensible Authentication Protocol (EAP) framework for secondary authentication between the UE and the SP. However, the secondary authentication methods have not been formally verified, so this paper proposes a Secondary Authentication Protocol (SAP) for service authentication and provides a comprehensive formal analysis using ProVerif a security protocol verifier. Finally, it conducts a security analysis on the protocol's security properties