Blockchain-Based Secure Authentication and Authorization Framework for Robust 5G Network Slicing

The rapid evolution of heterogeneous applications signifies the requirement for network slicing to cater to diverse network requirements. Network Functions (NFs), which are the essential elements of network slices, are required to communicate with each other securely to facilitate network services. Certificates are the established method to authenticate each other. However, dynamic certificate management while allowing NFs to communicate in a multi-operator environment is arduous. Also, sharing NFs between network slices originates authorization-related security challenges such as unauthorized service utilization, deceptive Denial of Service attacks, and data leakages from network slices. In this paper, we develop a novel framework to address the security challenges related to authentication and authorization in 5G network slicing systems. A blockchain-based multi-party distributed certificate management framework with secure communication protocols is developed using elliptic curve cryptography to facilitate certificate services for multi-operator environments. Also, we propose a blockchain-based NF authorization framework to mitigate the security vulnerabilities in NF sharing between network slices. We implement the proposed framework using Hyperledger Fabric blockchain with Java chain codes and perform comprehensive experiments to show the significance of our framework.The Ability to mitigate the single point of failure with respect to state-of-the-art, including traditional certificate authorities and blockchain-based certificate authorities, time analysis for certificate generation, and the potential to eliminate the mentioned authorization attacks are some of the experiments conducted.Also, we have shown that our framework is secure using informal and formal (using Real-Or-Random (ROR) logic and Scyther Validation tool) security verification mechanisms.