An enhanced hybrid wireless mesh protocol (E-HWMP) protocol for multihop vehicular communications

Integration of Vehicular Ad-hoc Network (VANET) and Universal Mobile Telecommunication System (UMTS) is a promising architecture for future machine-to-machine applications. This integration helps the vehicles have steady Internet connection through UMTS network and at the same time can communicate with other vehicles. However, the dead spot areas and unsuccessfully handoff processes due to the high speed of the vehicles can disrupt the implementation of this kind of architecture. In this paper, a new Simplified Gateway Selection (SGS) scheme for multihop relay in VANET-UMTS integration network is proposed. The main aim of this research is to enhance the integration between VANET and UMTS network, and extend the coverage in the area where there is no coverage, and reduce the amount of overhead, and reduce delay metrics, and increasing the packet delivery ratio, and also to reduce the dead spot in VANET-UMTS network. An enhanced version of HWMP is a combination of IEEE802.11p and IEEE802.11s for multihop vehicular communications is proposed. An integrated simulation environment combined of VanetMobiSim and NS2 is used to simulate and evaluate the proposed scheme. The simulations results show that, E-HWMP protocol performed better than Ad-hoc on demand Distance Vector (AODV) routing protocol. Furthermore, E-HWMP is compared with other cluster-based gateway selection that used in the previous works; the result shows that our E-HWMP protocol outperforms the other cluster based gateway selections schemes in terms of connection delay, control packet overhead, packet delivery ratio and overall throughput.