Disabling misbehavior with traffic constraints in WLANs

In this paper, we deal with vulnerabilities in IEEE 802.11 DCF protocol itself and its interaction with transmission control protocol (TCP) protocol. Selfish configurations at medium access control or TCP layer give an increased bandwidth share for selfish stations, and malicious operations disturb overall network operations. We first analyzed the bandwidth allocation for each station under the assumption that all the stations behave well by obeying the protocol. We then expressed the bandwidth allocation with the traffic constraints in network calculus theory in order to guarantee the fair access for well-behaving stations in the presence of misbehaving stations. Based on the network calculus model, we constructed the framework of protecting well-behaving stations from malicious or selfish behaviors, called NetPro. We then built up the proposed NetPro framework in a simulation environment and an empirical test-bed, and we carried out a performance evaluation study. The results indicate that the proposed network calculus-based protection framework successfully secures well-behaving stations from selfish or malicious misbehaviors.