Partial Deafness: A Novel Denial-of-Service Attack in 802.11 Networks

We present a new denial-of-service attack against 802.11 wireless networks. Our attack exploits previously discovered performance degradation in networks with substantial rate diversity. In our attack, the attacker artificially reduces his link quality by not acknowledging receptions (which we call “partial deafness” because an attacker pretends to have not heard some of the transmission), thereby exploiting the retransmission and rate adaptation mechanisms to reduce Medium Access Control (MAC)-layer performance. As compared to previously proposed attacks, the partial deafness attack is particularly strong because the attacker does not necessarily need any advantage over normal users in terms of transmission power, computation resources, or channel condition. Previous work has shown that time fairness in sharing the wireless medium can improve network throughput. We show that time-based regulation at the data queue of the access point can similarly mitigate the negative impact of a partial deafness attacker.