Optimization of hierarchical routing protocols

This paper concentrates on hierarchical routing protocols and their optimization. In a hierarchical routing protocol the network is divided into independent routing areas so that a node has complete routing information on its partition, but only reduced routing information of the “outside world” (i.e. the other partitions). Such routing protocols have been introduced in the early 1980s in order to decrease the overhead of dynamic routing protocols in large networks. However, such an approach may degrade the network performance. m of this work is to understand and quantify some aspects of the influence of this clustering process on network performance, and to determine how a given network (of a given topology) should be clustered under some optimization criteria. roblem has been already considered in the past, using a deterministic worst-case approach, for different optimization criteria. We generalize and refine the known results using a random geometric approach. This framework allows us to calculate explicitly the averages of various relevant variables (such as the size of the routing table and connection set-up latency) as a function of the topological parameters (such as the number of hierarchical levels). Optimum structures are then easily deduced.