The Vehicular ad hoc network (VANET) is an emerging new technology. Developing multi-hop routing protocols for urban VANETs is a challenging task. VANET is one of the influencing areas for the improvement of Intelligent Transportation System (ITS) in order to provide safety and comfort to the road users. Besides safety applications VANET also provide comfort applications to the road users. Automated highway systems and intelligent transportation systems (ITS) are introduced to accelerate the development, in order to increase road safety and reduce the number of accidents , as mobile wireless devices became an essential part of our lives, and the ‘anywhere, anytime’ connectivity concept is gaining attraction, Internet access from vehicles is in great demand. This paper presents a comprehensive study and comparisons of various routing protocols.

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Vehicular adhoc network (VANET) ITS Routing protocols.