Wireless Industrial Control Networks Research Articles

Stability analysis of token-based wireless networked control systems under deception attacks

Currently cyber-security has attracted a lot of attention, in particular in wireless industrial control networks (WICNs). In this paper, the stability of wireless networked control systems (WNCSs) under deception attacks is studied with a token-based protocol applied to the data link layer (DLL) of WICNS. Since deception attacks cause the stability problem of WNCSs by changing the data transmitted over wireless network, it is important to detect deception attacks, discard the injected false data and compensate for the missing data (i.e., the discarded original data with the injected false data). The main contributions of this paper are: (1) With respect to the character of the token-based protocol, a switched system model is developed. Different from the traditional switched system where the number of subsystems is fixed, in our new model this number will be changed under deception attacks. (2) For this model, a new Kalman filter (KF) is developed for the purpose of attack detection and the missing data reconstruction. (3) For the given linear feedback WNCSs, when the noise level is below a threshold derived in this paper, the maximum allowable duration of deception attacks is obtained to maintain the exponential stability of the system. Finally, a numerical example based on a linearized model of an inverted pendulum is provided to demonstrate the proposed design.

Design of Hybrid Wired/Wireless Fieldbus Network for Turbine Power Generation System

Hybrid fieldbus network integrating wireless networks with existing wired fieldbuses has become new a research direction in industrial automation systems. In comparison to wired fieldbuses, the hybrid wired/wireless fieldbus network has a different system architecture, data transmission mechanism, communication protocol, etc. This leads to different challenges that need to be addressed. This paper proposes a hybrid wired/wireless fieldbus network which consists of a wireless industrial control network (WICN), a wired PROFIBUS-DP (Process Field Bus-Decentralized Periphery) fieldbus network, and a wired MODBUS/TCP (Mod Bus/Transmission Control Protocol) fieldbus network. They are connected by a new gateway which uses a shared data model to solve data exchange in different network protocols. In this paper, we describe the architecture of the proposed hybrid wired/wireless fieldbus network and data transmission mechanisms in detail, and then evaluate the performance of hybrid fieldbus network via a set of experiments. The experiment results confirm that the proposed hybrid wired/wireless fieldbus network can satisfy the performance requirement of industrial network control systems. Furthermore, in order to further investigate feasibility of the proposed hybrid wired/wireless fieldbus network, it is deployed at a steam turbine power generation system, and the performance figures obtained further verify its feasibility and effectiveness.

Integration Infrastructure of Token-Based Industrial WSN and TCP

As some prevalent wired networks in industrial field are based on TCP, we proposed a novel integration infrastructure of token-based industrial WSN protocol and TCP, so as to make the application of wireless communication technologies more flexible. In the paper, a protocol conversion infrastructure is presented, which is based on data mapping mechanism. The protocol converter includes two modules: Wireless Industrial Control Network(WICN) master module and TCP host module. WICN master module owns an exclusive data buffer called WICN data buffer. TCP host module also has its own data buffer which is named TCP data buffer. A public data area is used for realizing the data mapping between WICN data buffer and TCP data buffer. By the data mapping mechanism, a station in wired network segment could get the data from WICN by accessing TCP data buffer, and WICN slave station could get the data from wired network via WICN data buffer. By the protocol conversion mechanism based on data mapping, flexible data exchange of heterogeneous networks could be realized.