A Model to Prevent Gray Hole Attack in Mobile Ad-Hoc Networks

—Over the past few years, Mobile Ad-hoc Networks (MANET) has been playing an important role in ubiquitous networks based on its ability to support mobility without depending on infrastructure-based design, dynamic topology, and thus, are known as decentralized environment. One of the advantages of MANET is that its nodes can act both as routers and hosts. This, therefore, implies that its nodes can transmit packets between source to destination nodes. As a result of such and many more advantages, these networks are more vulnerable to different types of network attacks. In the recent past, several secured routing protocols were proposed and implemented for MANET. However, those protocols cannot fully guarantee security within these networks in terms of Denial of Services (DoS) attacks such as black hole and gray hole attacks. The review of the literature showed that existing solutions cannot always ensure true node classification. This is because MANET’s cooperative existence sometimes leads to the false exclusion of innocent nodes and/or proper classification of malicious nodes. A new Gray Hole Prevention (GRAY-HP) algorithm for the detection of malicious nodes with the actual high accuracy ratio of node classification is proposed in this paper. The proposed algorithm employs and modifies the gray-attack prevention technique known as Secure Detection Prevention and Elimination Gray Hole (SDPEGH), and the proactive scheme. It has been confirmed by Network Simulator 2 (NS2) computer simulation that the proposed algorithm outperforms the Genetic Algorithm to Bacterial Foraging Optimization (GA-BFO) and Rough Set Theory (RSetTheory) algorithms in terms of throughput, routing overhead and delivery ratio. The proposed GRAY-HP algorithm guarantees the successful elimination of Gray hole nodes, while it also ensures that no legitimate nodes are excluded