Search-Based Stress Testing of Wireless Network Protocol Stacks

The operation of wireless network protocol stacks is heavily dependent on the actual deployment of the system and especially on the corresponding network topology, e.g. due to channel contention. The nature of wireless communication does not allow for a-priori determination of network topology, network-defining metrics such as neighbor density and routing span may drastically differ for various deployments. Therefore, it is a difficult problem to foresee and consider the large number of possible topologies that a system may run on during protocol stack development. We propose to use an automated approach for searching topologies for which a protocol stack exhibits particularly poor quantitative performance. We formulate stress testing of protocol stacks on specific topologies as a multi-objective optimization problem and use an evolutionary algorithm for finding a set of small topologies that particularly stress the protocol stack of a wireless network. For searching the topology space, we present novel problem-specific variation operators and show their improvements on search performance in case studies. We showcase our results on stress testing using two protocol stacks for wireless sensor networks.