Issues of Routing in VANET

In this study we try to figure out the problems and challanges that became hurdle for the reliable routing in Vehicular Adhoc Network.We selected topology and position based ad hoc routing protocols and compare their performance in VANET.We carried out different simulations of several topology and postion based routing protocols against each other.From the simualtion results we realize that postion based routing protocols have more promising results than topology based protocols.Furthermore in this study we conclude that position based routing should be adopt in order to provide more reliable routing in highly dynamic nature of VANET.