  The emerging Internet of Things (IoT) applications that leverage ubiquitous
connectivity and big data are facilitating the realization of smart everything
initiatives. IoT-enabled infrastructures have naturally a multi-layer system
architecture with an overlaid or underlaid device network and its coexisting
infrastructure network. The connectivity between different components in these
two heterogeneous interdependent networks plays an important role in delivering
real-time information and ensuring a high-level situational awareness. However,
IoT-enabled infrastructures face cyber threats due to the wireless nature of
communications. Therefore, maintaining network connectivity in the presence of
adversaries is a critical task for infrastructure network operators. In this
paper, we establish a three-player three-stage dynamic game-theoretic framework
including two network operators and one attacker to capture the secure design
of multi-layer interdependent infrastructure networks by allocating limited
resources. We use subgame perfect Nash equilibrium (SPE) to characterize the
strategies of players with sequential moves. In addition, we assess the
efficiency of the equilibrium network by comparing with its team optimal
solution counterparts in which two network operators can coordinate. We further
design a scalable algorithm to guide the construction of the equilibrium
IoT-enabled infrastructure networks. Finally, we use case studies on the
emerging paradigm of the Internet of Battlefield Things (IoBT) to corroborate
the obtained results.
