A Framework for Scalable Hierarchical Routing in Mobile Ad Hoc Networks

Abstract

The theoretical performance advantages of dividing a network into independent routing domains is well known; however, the actual benefits are hard to quantify and are often not sufficient to outweigh the added complexity. Justification of domains is especially hard in mobile ad hoc networks (MANETS), because reconfiguration overhead increases and use of single interface routers. Nevertheless, we believe that with the right domain configuration and inter-domain routing protocol we can get better performance using hierarchy than flat routing, especially in heterogeneous and dynamic networks. This paper proposes a framework for scalable routing in MANETs based on auto-configured optimized routing domains and an enhanced inter-domain routing scheme. To minimize overall overhead, the inter-domain routing protocol exploits existing messages needed for domain maintenance. The framework allows different routing protocols to run in each domain. OPNET simulations show the benefits of the proposed approach using OLSR for intra-domain routing. Results show significant reduction in protocol overhead, increased route stability and increased route availability in a dynamic heterogeneous network.