A Performance Evaluation of Load Balancing and QoS-aware Gateway Discovery Protocol for VANETs

Recently we have witnessed a growing interest in Vehicular Ad hoc Networks from the ITS community. Several potential applications of Vehicular Networks aiming at integrating service discovery mechanisms and the latest Internet access technologies are envisioned. However, several challenging issues, such as gateway discovery among others, remain to be resolved before VANET technology becomes a commodity. Indeed, in this case, it is very essential to provide clients with gateway services that better suit their requests while balancing the load on the gateways, in order to reduce the gateways congestion problem. In this paper, we propose to evaluate the performance of a load balanced and introduce a new QoS gateway discovery protocol (Collaged) that permits the connection to heterogeneous wireless networks. The protocol guarantees balancing the load at the gateways levels, as well as the routing paths between gateways and gateway requesters. It also permits gateway requesters to choose and connect to the gateways that satisfy the QoS required by the vehicles. We present our protocol, and discuss its performance evaluation using an extensive set of simulation experiments. Our results indicate that significant improvement were achieved using QoSLAGAD protocol when compared to LAGAD while guaranteeing QoS and balancing the gateways' load.