Enhancing Security in Multi-Controller SDMN Environments: A Novel 5G Access Authentication Protocol

In recent years, mobility has become one of the most important aspects of all networks, including multi-controller SDMNs. Once authenticated, mobile users must be able to move freely between domains without losing access to the provided network services. To this aim, once authenticated, mobile users must be able to re-authenticate every time they move from their original domains. In this study, we present a novel 5G access authentication protocol designed specifically for multi-controller SDMN environments. The paper elaborates on the initial authentication procedure as well as the re-authentication process inherent to this protocol. In our proposed protocol the mobile user will not need to reach the authentication server for the re-authentication process. It provides the controller with its MSK token allowing him to approve the re-authentication request if the MSK token is valid. This will generate low latency improvement in terms of handover time. A comprehensive analysis is conducted to assess the robustness of the proposed authentication mechanism against diverse cyber attacks. Furthermore, an analytical equation for quantifying the communication costs involved in both the initial authentication and subsequent re-authentication processes is provided. In addition, to validate the security robustness of the proposed 5G access authentication protocol, we utilize the Automated Validation of Internet Security Protocols and Applications (AVISPA) tool.