802.11 DCF Denial of Service Vulnerabilities

Abstract

This paper addresses denial of service vulnerabilities (DOS) in 802.11 wireless LANs that arise from the 802.11 distributed coordination function (DCF). We demonstrate that the DCF is vulnerable to equivalent DOS attacks at both the MAC and PHY layers. Denial of service attacks against the DCF are easily staged by a single adversary and affect both infrastructure and mobile ad hoc networks. These attacks are very effective and there are no workable counter-measures when using the standard MAC protocol. When staged by a shrewd adversary these denial of service attacks reveal little information about the attacker and provide almost no forensic evidence. We have demonstrated that 802.11 wireless LANs are particularly vulnerable to denial of service attacks and should not be used where availability is essential.