Book

Description

Mobile Ad Hoc Networks (MANETs) are infrastructure-less, self-organizing networks where all nodes act as routers and participate in route discovery and maintenance. This decentralized and dynamic nature, while highly flexible, introduces significant challenges including node mobility, limited bandwidth and power, and security vulnerabilities. Routing protocols are the backbone of MANETs, but they are frequently targeted by malicious nodes, making secure communication a critical concern. The widely used Ad-hoc On-Demand Distance Vector (AODV) routing protocol efficiently establishes routes on demand using sequence numbers and hop counts, but it was originally designed without security in mind. Its control packets, transmitted in clear text, can be manipulated by attackers, enabling unauthorized nodes to advertise false routes and disrupt network operations. To address these vulnerabilities, this research focuses on enhancing the security of AODV using lightweight cryptographic mechanisms. Two novel schemes are proposed: a Message Digest Mechanism and a Message Digest with Secret Key Mechanism, designed to ensure integrity and authenticity of routing messages while maintaining low computational overhead and minimal power consumption. Existing secure protocols, such as SAODV, provide partial solutions but often introduce higher complexity or fail under high traffic conditions. The proposed schemes integrate message digest techniques to protect against malicious attacks, offering a practical and efficient security solution for dynamic MANET environments. The performance of these mechanisms is evaluated using NS2 simulations under varying network scenarios and traffic loads, including Constant Bit Rate (CBR) traffic. Results demonstrate that under low traffic, AODV with the proposed mechanisms performs comparably to SAODV in terms of packet delivery and routing load. As traffic increases, the proposed solutions outperform SAODV, achieving higher packet delivery ratios, reduced routing overhead, and improved routing efficiency. These findings indicate that the proposed mechanisms are scalable, energy-efficient, and effective in securing MANET routing protocols.