Determining the optimal configuration for the zone routing protocol

The zone routing protocol (ZRP) is a hybrid routing protocol that proactive ly maintains routes within a local region of the network (which we refer to as the routing zone). Knowledge of this routing zone topology is leveraged by the ZRP to improve the efficiency of a reactive route query/reply mecha nism, The ZRP can be configured for a particular network through adjustment of a single parameter, the routing zone radius. In this paper, we address the issue of configuring the ZRP to provide the best performance for a part icular network at any time. Previous work has demonstrated that an optimall y configured ZRP operates at least as efficiently as traditional reactive f lood-search or proactive distance vector/link state routing protocols (and in many cases, much more efficiently), Adaptation of the ZRP to changing ne twork conditions requires both an understanding of how the ZRP reacts to ch anges in network behavior and a mechanism to allow individual nodes to iden tify these changes given only limited knowledge of the network behavior. In the first half of this paper, we demonstrate the effects of relative node velocity, node density, network span, and user data activity on the perform ance of the ZRP, We then introduce two different schemes ("min searching" a nd "traffic adaptive") that allow individual nodes to identify and appropri ately react to changes in network configuration, based only on information derived from the amount of received ZRP traffic. Through test-bed simulatio n, we demonstrate that these radius estimation techniques can allow the ZRP to operate within 2% of the control traffic resulting-from perfect radius estimation.