Mobile Ad-hoc Networks (MANETs) are decentralized, self-organizing wireless networks that operate without fixed infrastructure. Despite their flexibility, they are highly susceptible to congestion and black hole attacks, which significantly degrade throughput, packet delivery ratio (PDR), and overall Quality of Service (QoS). This paper introduces an enhanced hybrid routing protocol Black Hole and Congestion Overcome AOMDV (IH-AOMDV) as an optimized extension of the Ad-hoc On-Demand Multipath Distance Vector (AOMDV) protocol. The proposed approach integrates congestion awareness and security mechanisms by combining throughput-based congestion detection with sequence-number-based route validation to identify and isolate congested and malicious nodes in real time. Simulation experiments conducted in NS2.35 across a 1000×1000 m network with 15–35 nodes demonstrate that IH-AOMDV achieves up to 90–100% throughput, improves the packet delivery ratio by 35%, reduces end-to-end delay by 45%, and decreases packet loss by approximately 40% compared to standard AOMDV. The results confirm the robustness, scalability, and adaptability of IH-AOMDV, establishing it as a reliable routing framework for secure and congestion-free MANET communication in dynamic environments such as military, vehicular, and disaster response networks.
Iticha et al. (Tue,) studied this question.