5. Conclusion and future work
In this paper, a novel clustering algorithm, a CH election algorithm and a game theory based IDS framework for VANETs have been proposed. The proposed clustering algorithm ensures the stability of the IDS framework by generating stable vehicular clusters with enhanced connectivity among member vehicles. CH and agent nodes election algorithms are then executed to elect the CH and a set of agent nodes for each cluster. The proposed IDS framework uses the the agent nodes, the CHs and the RSUs operating at three different levels of the vehicular network to carry out the intrusion detection operation in a distributed manner. The framework uses a set of specification rules based on the Packet Drop Rate (PDR), Packet Forwarding Rate (PFR), Receive Signal Strength Indicator (RSSI) and Duplicate Packet Rate (DPR) values of the vehicles, along with a lightweight neural network based classifier module for detecting malicious vehicles. In addition, the proposed framework minimizes the volume of IDS traffic introduced into the vehicular network by modeling the interaction between the IDS and the malicious vehicle as a two player non-cooperative game, and by adopting a probabilistic IDS monitoring strategy based on the Nash Equilibrium of the game.
The clustering algorithm proposed in the paper only considers the vehicles that stopped at the traffic signal and vehicles approaching the road intersection point with relatively low speed. For our future work, we envisage to formulate a dynamic clustering algorithm, which takes into account the vehicles in motion for generating stable vehicular cluster. We also aim to improve the DR and minimize the FAR rate of the proposed IDS framework by analyzing the performances of various other classifiers using Support Vector Machine (SVM), Decision Tree, Logistic Regression, Multilayer Perceptron (MLP) etc. Additionally, we also aim to extend and implement the proposed IDS framework to various other networks like Software Defined Network (SDN), Delay Tolerant Network etc., in future.