Clustered Multicast Protocols for Warning Message Transmissions in a VANET

The VANET architecture is evolving to support safety messaging services in vehicular networks using different wireless networking standards. The VANET architecture was predominantly developed using the IEEE 802.11p architecture. However, with the arrival of 5G technologies, the LTE standard is actively considered to support vehicular networking requirements. This paper proposes an LTE-based multi-hop multicast communication network architecture to support Warning Message (WM) transmissions in a vehicular network by sharing the network resources with other type messages such as the Cooperative Awareness Message (CAM). We propose a multicast communication architecture to distribute the warning messages using two communication protocols to all vehicles and infrastructure nodes in an Area of Relevance (AOR). The proposed message distribution protocols are referred to as the Clustered Multi-hop Multicast Protocol (CMMP) and the Clustered Multi-hop Broadcast and Multicast Protocol (CMBMP). Both protocols use distributed resource allocation techniques in a LTE network. Performance of these protocols is analyzed using an OMNET++/SimuLTE/Veins/SUMO based simulation model which shows that the performance of the proposed protocols is significantly better than other recently published protocols which support the warning message transmission in hybrid LTE networks. Simulation results show that the proposed protocols introduce low WM delivery delay as well as maintaining high WM delivery ratio.