SAWAN: a survivable architecture for wireless LANs

This paper describes survivability schemes against access point (AP) failures in wireless LANs. It particularly aims for resiliency and survivability against multistage attacks where the adversary is successful in compromising the AP, and then targets the survived but more vulnerable network. This is true in real life where the adversary knows that survivability is a design consideration built into the network. It then performs a multistage targeted attack that is aimed at compromising the survived network that may have vulnerabilities. We first present a unique infrastructure for an ad-hoc migration scheme (IAMS) where the nodes under a failed AP form an ad-hoc network and reconnect to the network using available neighboring APs. We then present a scheme for isolating and removing any malicious nodes from the ad-hoc network routes in a transparent manner once the malicious nodes have been identified. This will minimize the chances of further attacks in the survived network, and the removal is done in a distributed fashion without the nodes exchanging any information between them. We report the results of our simulations performed using the network simulation tool GloMoSim.