Traffic-aware hybrid routing algorithm for mobile ad-hoc networks

Wireless ad-hoc networks have many different characteristics from previous centralized networks. While the infrastructure based networks usually employ the simple routing protocol because every node can reach the coordinator in a single hop, some specific situations, i.e., unplanned dynamic links and multi hop environment, were required in ad-hoc networks. All nodes engaging in communication under the ad-hoc networks should be operated as a router. For this, two routing approaches are previously designed for ad-hoc networks; proactive and reactive routing, and they differently have pros and cons from each other. Moreover, to integrate their advantages in case by case, hybrid approach is consistently researched, and Zone Routing Protocol (ZRP) was motivating many recent hybrid protocols. ZRP uses proactive routing to the node located within the zone defined by the specific number of hops, while it uses reactive routing to other nodes. However, proactive routing is applied only within the zone defined by the number of hops. In this, the zone is formed regardless of whether real data communication occurred frequently or not. In this paper, we propose a new routing scheme called Traffic Aware Dynamic Zone Routing (TA-DZR) protocol which employs the zone method but forms customized zone using traffic load, by a new decision method named Dynamic Zone Decision (DZD). The DZD selects nodes that are good to use proactive routing based on the traffic load. The customized proactive routing zone is formed around the route path from source to the selected destination. By considering traffic awareness, TA-DZR can decrease the number of transmissions and can reduce the total energy consumption. After the description of TA-DZR, the performance is demonstrated with simulation results which show that the number of transmissions decreases in overall network, and that the energy consumption is also reduced. Additionally, we validate that the end-to-end delivery delay is reduced and that the packet delivery ratio (PDR) is improved. These enhancements are caused by reducing overall network congestion.