Biblio

This paper proposes a new strategy, named resident strategy, for defending IoT networks from repeated infection of malicious botnets in the Botnet Defense System (BDS). The resident strategy aims to make a small-scale white-hat botnet resident in the network respond immediately to invading malicious botnets. The BDS controls the resident white-hat botnet with two parameters: upper and lower number of its bots. The lower limit prevents the white-hat botnet from disappearing, while the upper limit prevents it from filling up the network. The BDS with the strategy was modeled with agent-oriented Petri nets and was evaluated through the simulation. The result showed that the proposed strategy was able to deal with repeatedly invading malicious botnets with about half the scale of the conventional white-hat botnet.

Cyber-Physical Systems (CPS) is mostly deployed in security-critical applications where their failures can cause serious consequences, and therefore it is critical to evaluate its availability. In this paper, an architecture model of CPS is established from the perspective of object-oriented system. The system is a unified whole formed by various independent objects (including sensors, controllers and actuators) through communication connection. Then the paper presents the Object-oriented Timed Petri Net to model the system. The modeling method can be used to describe the whole system and the characteristics of the object. At the same time, the availability analysis of the system is carried out by using the mathematical analysis method and simulation tool of Petri net. Finally, a concrete case is given to verify the feasibility of the modeling method in CPS availability analysis.

The authors have proposed the Fallback Control System (FCS) as a countermeasure after cyber-attacks happen in Industrial Control Systems (ICSs). For increased robustness against cyber-attacks, introducing multiple countermeasures is desirable. Then, an appropriate collaboration is essential. This paper introduces two FCSs in ICS: field network signal is driven FCS and analog signal driven FCS. This paper also implements a collaborative FCS by a collaboration function of the two FCSs. The collaboration function is that the analog signal driven FCS estimates the state of the other FCS. The collaborative FCS decides the countermeasure based on the result of the estimation after cyber-attacks happen. Finally, we show practical experiment results to analyze the effectiveness of the proposed method.