**3.2 Vehicular specific communication technologies**

This category includes communication technologies which are dedicated to vehicular applications and actually were the result of additional communication requirements posed by ITS applications. Dedicated communication standards are in development for cooperative systems. At the access layer, a convergence towards the IEEE 802.11p standard can be observed, while standardisation on the network and transport layer is still in progress. Several prototype implementations exist and are used in demonstrations and pilots. IP communication (focus is on IPv6) can be used on top of 802.11p, but due to the highly dynamic character of the network (i.e. movement of vehicles, relatively short communication distances) dedicated standards have been developed and are being standardised by ISO and ETSI. The most important of them, namely DSRC, WAVE and CALM, are illustrated below.
