An effective intrusion detection approach for OLSR MANET protocol

The optimized link state routing (OLSR) protocol is a proactive mobile ad hoc network (MANET) routing protocol. Security aspects have not been designed into the OLSR protocol and therefore make it vulnerable to various kinds of attacks. Recent research efforts have focused on providing authentication and encryption techniques to secure the OLSR protocol against attacks from outside intruders. A second line of defense is required to provide intrusion detection and response techniques in protecting the OLSR protocol against attacks from inside intruders. In this paper, we describe security threats to the OLSR MANET routing protocol and present an intrusion detection solution based on protocol semantics checking. Our approach is based on semantic properties that are implied in the protocol definition and specify the correct OLSR routing update behavior. Conflict checking based on semantic properties is applied in every MANET node. Any abnormal protocol semantics triggers an intrusion alarm. While we use OLSR as an example, we argue that the presented approach can be applied to any multi-point relay (MPR) proactive MANET protocol.