A capacity and utilization study of mobile ad hoc networks

We develop an empirical technique to determine the capacity of a mobile ad hoc network. We assume that the network runs on-demand routing and carrier sense-based medium access protocols. The technique, however, is general and should apply to other types of protocols. We develop a tool that determines the network capacity given session-level traffic and node mobility traces. We compare the network capacity so determined with the actual network utilization from output statistics generated by a comprehensive simulator. It is observed that network capacity increases with node mobility; but the routing and medium access protocols fail to take advantage of the increased capacity. Even with high loads, a significant portion of the network capacity is not utilized, while the routing performance remains poor. This study indicates that there is a significant scope for designing aggressive routing protocols that utilize the network capacity better to improve routing performance.