Secure node misbehaviors in mobile ad hoc networks

Node misbehaviors are serious attacks for routing protocols in Mobile Ad Hoc Networks (MANET). In this paper, two types of node misbehaviors, single intermediate node packet dropping and group nodes wormhole attacks, are exclusively identified for the Secure Ad Hoc On-demand Distance Vector Routing protocol (SAODV). The countermeasures are proposed to protect against these node misbehaviors, and therefore further enhance the security of SAODV, such that a near perfect secure routing protocol is achieved. To protect SAODV against any form of single insider attacks, we assign the task of single malicious intermediate nodes detection and isolation to a group of nodes since there is no centralized authority in ad hoc networks. These nodes lie around active paths in MANET. Nodes use the same digital signatures that are used for routing in SAODV to provide authentication and integrity protection for routing information. For wormhole attack, in which more than one malicious nodes work in group, a novel mechanism without time synchronization or location information techniques to detect this attack is proposed. Our simulation results show the network performance degradation after incorporating the above two mechanisms in SAODV is negligible.