A New Deployment Schema Using Dynamic Relay Vehicle to Improve VANETs Connectivity in Urban Environment

Abstract

Vehicular ad-hoc network (VANETs) have emerged as promising technology to support traffic safety applications of intelligent transportation system (ITS). One of the most important challenges facing VANET is the connectivity, due to obstacles, high mobility, dynamic topology which leads to disconnection problem. Deploying road Sid unite (RSU) to improves VANET connectivity is considered as a highly cost solution. Previous researches suggested diverse RSU deployment schemes and algorithms to solve the RSU deployment issue in order to achieve better network connectivity with minimum number of RSU. In this paper we propose dynamic relay node as replacement to RSU with zero infrastructure. It's Using key metrics of interest (such as connection duration, re-healing time, receiving time) we provide thorough visualization for network connectivity of urban VANETs with dynamic relay node. It is not only a low-cost solution, but it is practical solution since it does not require RSU installation or maintenance. Simulations are carried out in ns2 to evaluate the performance of dynamic relay node in urban environment. The proposed scheme proves its efficiency through increasing the vehicle density in the road and by increasing relay vehicle velocity. The result shows that the proposed scheme improve the network connectivity as the number of relays increased up to four dynamic relay nodes.