IEEE 802.11 Denial of Service attack detection in MANET

Denial of Service (DoS) attack is a simple form of attack that has significant impact on the legitimate network users in terms of available bandwidth. The purpose of this paper is to detect and identify the attacker who is employing Denial of Service attack to disrupt the network in Mobile Ad-hoc Networks (MANET) using IEEE 802.11 DCF protocols [1][2][3]. The detection process will be examined in a mobile environment with multiple PHY layer techniques (FHSS, DSSS, and OFDM) employing different MAC layer protocols (IEEE 802.11, IEEE 802.11b, and IEEE 802.11g) Attackers manipulate the IEEE 802.11 DCF standards on their machines to illegally increase the probability of successful packet transmission on the expense of the legitimate node´s bandwidth. The DoS attacker does not have valid information in the transmitted packets but the attacker´s goal is to capture the channel to prevent legitimate users from communicating. DoS attack can be performed and targeted to affect any layer of the OSI layers, in this paper we only deal with attacks on the MAC layer. The theoretical network throughput in terms of maximum number of packets transmitted per second will be derived using two dimensional Markov Chain [4] to determine the network capacity. Solutions of the Markov Chain model will be validated by network simulation [5] to determine the baseline for the maximum achievable throughput in the network under normal conditions where the standards are followed properly.