Date Added: Jan 2010
Hierarchical routing is a common practice in actual Internet networks. This kind of routing allows nodes and routers to get small routing tables and small routing overhead. On the opposite side, routing in MANETs is flat; therefore, nodes have to learn how to reach each node in the network. It means large routing tables, impact in the look up algorithm and large routing overhead. In this paper the authors analyze the advantages of using hierarchical routing in MANETs under specific scenarios, showing the reduction of routing overhead from a factor of N2 to N2/k (being N the number of nodes and k the number of subnets).