**3.3. Clustering in layers**

Clustering can simplify essential functions like bandwidth utilization, routing, and channel access. In MAC layer, it can provide a fairer and reliable channel access to all vehicles in network. This can lead to increase in the reliability of packets and scalability of the network. In network layer, clustering for routing can find the closest vehicles to intended destination. Furthermore, it reduces the number of broadcast and flooding messages in the network. In addition, the overhead for clustering is reduced if the same scheme is used for MAC and routing.
