DAG-Based Attack and Defense Modeling: Don't Miss the Forest for the Attack Trees
IEEE 802.11s is an emerging standard for wireless mesh networks. Networks based on IEEE 802.11s directly benefit from existing security mechanisms in IEEE 802.11. This limits the attack surface of IEEE 802.11s significantly for adversaries that cannot authenticate with the network. Mesh networks are, however, often conceived for community network scenarios, which are inherently more open than managed infrastructure networks. This openness entails an increased risk of insider attacks, i.e., attacks by compromised stations that can authenticate with the network. Currently, IEEE 802.11s is lacking adequate protection against such insider attacks. In this paper, we hence derive an attack model for insider attacks and present two insider attack strategies to which IEEE 802.11s networks are prone, namely impairing the network performance and preventing communication between a pair of nodes. We design countermeasures that allow to defend the wireless network against both types of attacks. Our implementations only incur marginal computational and memory overheads, while the network security is measurably strengthened.