  This paper deals with the design of scheduling policies for networked control
systems whose shared networks have limited communication capacity and the
controller to plant channels are vulnerable to jamming attacks. We assume that
among N plants, only M (< N) plants can communicate with their controllers at
any time instant, and the attack sequences follow an (m,k)-firm model, i.e., in
any k consecutive time instants, the control inputs sent to some or all of the
plants accessing the communication network, are deactivated at most at m (< k)
time instants. We devise a new algorithm to allocate the network to the plants
periodically such that stability of each plant is preserved under the
admissible attack signals. The main apparatus for our analysis is a switched
systems representation of the individual plants in an NCS. We rely on matrix
commutators (Lie brackets) between the stable and unstable modes of operation
of the plants to guarantee stability under our scheduling policies.
