Abstract Mobile ad-hoc network is a network without infrastructure where every node has its own protocols and services for powerful cooperation in the network. Every node also has the ability to handle the congestion in its queues during traffic overflow. Traditionally, this was done through Drop-Tail policy where the node drops the incoming packets to its queues during overflow condition. Many studies showed that early dropping of incoming packet is an effective technique to avoid congestion and to minimize the packet latency. Such approach is known as Active Queue Management (AQM). In this paper, an enhanced algorithm, called Fuzzy-AQM, is suggested using fuzzy logic system to achieve the benefits of AQM. Uncertainty associated with queue congestion estimation and lack of mathematical model for estimating the time to start dropping incoming packets makes the Fuzzy-AQM algorithm the best choice. Extensive performance analysis via simulation showed the effectiveness of the proposed method for congestion detection and avoidance improving overall network performance.

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[32] Yanfei F., Fengyuan R., and Chuang L., Design an Active Queue Management Algorithm based on Fuzzy Logic Decision, in Proceedings of IEEE International Conference on Communication Technology (ICCT'03) , vol. 1, pp. 286-289, April 2003. Essam Natsheh obtained his MSc in computer engineering from the Arab Academy for Science and Technology in Egypt, in 1999. He subsequently worked as a lecturer at Al-Alamiah Institute for Computer and Technology, SA, in 2002. He worked as a lecturer also at the Information Systems Department of the King Faisal University, SA, from 2002 to 2003. Since 2003, Natsheh has been a member of a research group headed by Dr. Jantan A. at the University Putra Malaysia, which investigates issues related to the design and analysis of ad-hoc wireless networks. Adznan B. Jantan obtained his MSc in digital systems from Cranfield Institute of Technology, UK, in 1982 and his PhD in speech recognition systems from the University College of Swansea, UK, in 1988. Since 2002, he is an associate professor at the Department of Computer and Communication System at the University Putra Malaysia, where he has been conducting research in computer networking, pattern recognition, and digital systems design. Sabira Khatunreceived her BSc (Hons.), MSc in applied mathematics and PhD on hydromagnetic stability from the University of Rajshahi, Bangladesh in 1988, 1990, and 1994, respectively. She received her second PhD in communications and networking from University Putra Malaysia in 2003. She became a lecturer at the Department of Computer Science and Engineering, University Khulna, Bangladesh in 1991, and promoted to assistant professor in 1994. She joined the Department of Computer & Communication Systems Engineering, University Putra Malaysia in 1998. She is an active researcher of Teman project and MyREN Research Community. She is a member of IEEE. Her research interest spans broadband and wireless communications, and network management, including software defined radio and IPv6. Shamala Subramaniam completed her PhD from University Putra Malaysia in 2002. Currently, she is a lecturer at the Department of Communication Technology and Networks, Faculty of Computer Science and Information Technology, University Putra Malaysia. Her research interest includes scheduling algorithms, congestion control, real-time systems, modeling, and simulation.