Strategies for enhancing routing security in protocols for mobile ad hoc networks

Mobile ad hoc network (MANET) is a new emerging field with its potential applications in extremely unpredictable and dynamic environments. These characteristics require the networks to have much harder security requirements than the contemporary networks. While current routing protocols do seem to adjust well to dynamically changing conditions, they offer either no security mechanisms at all or have only partial solutions for ensuring the correct routing. It is hard to simultaneously achieve both security and robustness in the routing protocols. In this paper, we analyze various possible threats to the routing protocols and introduce strategies to address the same. On one hand, routing protocol can be disrupted due to attacks from intruder nodes that do not belong to the network. On the other hand, routing is severely affected by the presence of compromised nodes that inflict unpredictable and undetectable Byzantine failure. We have addressed the issue of attacks from intruders by means of authentication techniques that rely on mutual trust between nodes. We also study the behavioral patterns of the nodes and isolate compromised nodes using a distributed approach. The effectiveness of our schemes is illustrated by means of extensive simulations using ns-2 Simulator. The routing protocol chosen for the study is AODV. We have observed the performance of the network with and without our secured routing scheme. (C) 2003 Elsevier Science (USA). All rights reserved.