On the performance of a scalable single-tier position based routing protocol for mobile ad-hoc wireless networks

This paper deals with the performance evaluation of a scalable single-tier routing protocol designed for operation in mobile ad hoc networking environments. The protocol under consideration is based on the superposition of link-state and position-based routing, and it employs a simplified way of localizing routing overhead, without having to resort to complex, multiple-tier routing organization schemes. Specifically we study the protocol's scalability measured by routing overhead, by calculating the average number of routing packets per node, as a function of the network size. The obtained results demonstrate that the average number of routing packets transmitted by a node is practically insensitive to the network size. This clearly indicates that our protocol possesses the scalability property which is very critical in mobile ad hoc networking environments, without having to resort to complicated and vulnerable hierarchical approaches. Moreover we compare the performance of our protocol with a non-realistic "ideal routing protocol" where packets are routed assuming continuous and accurate knowledge of the exact node position. Specifically we study the "route distortion" introduced by our protocol due to inaccuracies in the positions of other hosts known by the local host, and compare the number of hops needed to route data under our approach against the corresponding results obtained for the "ideal routing". The results indicate that for various mobility scenarios our protocol has nearly optimum data routing characteristics. Finally we discuss various design parameters related to the protocol's operation and we investigate their impact on the protocol's performance and effectiveness..