A Group-Based Multicast Service Authentication and Data Transmission Scheme for 5G-V2X

5G Vehicular to everything (5G-V2X) has grown more vigorously than ever before, and services massive vehicles can obtain provided by content providers via the network in all fields are widely acknowledged, such as listening to news channels and traffic channels. In the 5G-V2X network, content providers can provide service messages to a group of vehicles belonging to a specific area in point-to-multipoint transmission mode. However, various challenges are in front of the way when vehicles obtain multicast services due to the unique features of 5G-V2X, such as massive vehicles and strong mobility. In this paper, we present a typical vehicle multicast service model in 5G-V2X and propose a group-based multicast service authentication and data transmission scheme based on this model. In the scheme, massive vehicles within the same RAN coverage are constructed into a group and connected to the content provider to gain access to a multicast service using the distributed keys securely by the 5G home network. Subsequently, the multicast service key for protecting the multicast service data is distributed to each vehicle so that the multicast service data can be securely transmitted to vehicles in point-to-multipoint mode. The security analysis results using the formal verification tool and informal security analysis show that the proposed scheme supports the multicast services authentication and authorization, multicast service data protection, key distribution protection, anonymity, unlinkability, and protocol attack resistance. The performance analysis results regarding signaling, computational and communication overheads show that the proposed scheme outperforms other related schemes.