Reliability analysis of heterogeneous sensor-cloud systems against targeted attacks

Based on the wide application of cloud computing and wireless sensor networks in various fields, the Sensor-Cloud System (SCS) plays an indispensable role between the physical world and the network world. However, due to the close connection and interdependence between the physical resource network and computing resource network, there are security problems such as cascading failures between systems in the SCS. In this paper, we propose a model with two interdependent networks to represent a sensor-cloud system. Besides, based on the percolation theory, we have carried out a formulaic theoretical analysis of the whole process of cascading failure. When the system's subnetwork presents a steady state where there is no further collapse, we can obtain the largest remaining connected subgroup components and the penetration threshold. Theoretically, this result is the critical maximum that the coupled SCS can withstand. To verify the correctness of the theoretical results, we further carried out actual simulation experiments. The results show that a scale-free network priority attack's percolation threshold is always less than that of ER network which is priority attacked. Similarly, when the scale-free network is attacked first, adding the power law exponent λ can be more intuitive and more effective to improve the network's reliability.