Priority based routing protocol with reliability enhancement in Vehicular Ad hoc Network

This paper proposes a reliability enhancement routing protocol in Vehicular Ad hoc Network (VANET) called Priority based Routing Protocol with Reliability Enhancement (PRP-RE). Priority based Routing Protocol (PRP) was previously proposed to provide i) fully distributed routing protocol, ii) different quality of services (QoS) for different types of messages, iii) maximum message dissemination distance per hop of information relay. However, PRP cannot attain high reliability when dissemination distance becomes larger. With the reliability enhancement, implicit acknowledgement and retransmission mechanisms, PRP-RE are able to achieve both higher reliability and further message dissemination distance. PRP-RE is evaluated using network simulation tool named OMNeT++ in terms of average MAC delay as well as percentage of message reception and collision. The results show PRP-RE provides significant improvement in both reception rate and communication distance, with a little impact on MAC delay. In addition, PRP-RE is still able to maintain proportional MAC delay according to priorities of messages in fully distributed environment. Therefore, the PRP-RE presents a good balance of reliability, delay, and dissemination distance.