Response Time Analysis for Nonperiodic CAN Message Based on GI/G/1 Queue Model

Controller area network (CAN) has wide applications in modern industrial control systems. Automobile manufacturers use this communication protocol for vehicle control, which is subject to real-time and high-reliability performance. However, with the increasing actuators gathered in the vehicle, time delay will lead to a serious problem for the vehicle safety and performance control. Thus, the information transmission stability of the CAN message needs to be investigated. In order to find out the delay response time of nonperiodic CAN message in the vehicle bus area, the response of the message transmitted in the CAN bus is modeled based on the GI/G/1 queue theory. The test platform is developed to verify the methodology. In the experimental test, some conditions with different IDs, load ratios, and priorities are investigated. Experimental results are compared with the theoretical results, and the simulation results show that the method is valid and verify the real response delay time of nonperiodic CAN message.

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Detection and Blocking of Replay, False Command, and False Access Injection Commands in SCADA Systems with Modbus Protocol

Security and Communication Networks ◽

10.1155/2021/8887666 ◽

2021 ◽

Vol 2021 ◽

pp. 1-15

Author(s):

Rajesh L ◽

Penke Satyanarayana

Keyword(s):

Control Systems ◽

Area Network ◽

Core Component ◽

Industrial Control ◽

Industrial Control Systems ◽

Modbus Protocol ◽

Replay Attacks ◽

Scada Systems ◽

Process Plants ◽

The Impact

Industrial control systems (ICS) are being used for surveillance and controlling numerous industrial process plants in national critical infrastructures. Supervisory control and data acquisition (SCADA) system is a core component in ICS systems for continuous monitoring and controlling these process plants. Legacy SCADA systems are working in isolated networks and using proprietary communication protocols which made them less exposed to cyber threats. In recent times, these ICS systems have been connected to Internet and corporate networks for data sharing and remote monitoring. They are also using open protocols and operating systems. This leads to vulnerabilities of the system to cyberattacks. Cybersecurity threats are more prevalent than ever in ICS systems. These attacks may be external or internal. Modbus is a widely deployed communication protocol for SCADA communications. There is no security in design of Modbus protocol, and it is vulnerable to numerous cyberattacks. In this paper, we worked for False Command Injection attack, False Access Injection attack, and replay attacks on Modbus protocol. Initially, a real-time SCADA testbed was set up, and we envisaged the impact of these attacks on Modbus protocol data using the testbed. In this work, we used local area network (LAN) environment only for simulating the attacks. We assumed that the attacks penetrated the LAN network. We proposed and developed (a) a method to detect replay attacks by incorporating time stamp and sequence number in Modbus communications and (b) a frame filtering module which will block unauthorized attacks like False Command Injection and False Access Injection attacks to reach programmable logic controller (PLC). Numbers of attacks were simulated and the performance of the method was measured using attack block rate (ABR). It blocked 97% of malicious Modbus transactions or attacks to reach the PLC. It protects SCADA systems from attackers, which is a core component of industrial control systems. The solution enhanced the security of SCADA systems with Modbus protocol.

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Virtualization of Industrial Real-Time Networks for Containerized Controllers

Sensors ◽

10.3390/s19204405 ◽

2019 ◽

Vol 19 (20) ◽

pp. 4405 ◽

Cited By ~ 1

Author(s):

Sang-Hun Lee ◽

Jong-Seo Kim ◽

Jong-Soo Seok ◽

Hyun-Wook Jin

Keyword(s):

Control Systems ◽

Real Time ◽

Device Driver ◽

Area Network ◽

Industrial Control ◽

Worst Case ◽

Industrial Control Systems ◽

Virtualization Technology ◽

Limited Scope

The virtualization technology has a great potential to improve the manageability and scalability of industrial control systems, as it can host and consolidate computing resources very efficiently. There accordingly have been efforts to utilize the virtualization technology for industrial control systems, but the research for virtualization of traditional industrial real-time networks, such as Controller Area Network (CAN), has been done in a very limited scope. Those traditional fieldbuses have distinguished characteristics from well-studied Ethernet-based networks; thus, it is necessary to study how to support their inherent functions transparently and how to guarantee Quality-of-Service (QoS) in virtualized environments. In this paper, we suggest a lightweight CAN virtualization technology for virtual controllers to tackle both functionality and QoS issues. We particularly target the virtual controllers that are containerized with an operating-system(OS)-based virtualization technology. In the functionality aspect, our virtualization technology provides virtual CAN interfaces and virtual CAN buses at the device driver level. In the QoS perspective, we provide a hierarchical real-time scheduler and a simulator, which enable the adjustment of phase offsets of virtual controllers and tasks. The experiment results show that our CAN virtualization has lower overheads than an existing approach up to 20%. Moreover, we show that the worst-case end-to-end delay could be reduced up to 78.7% by adjusting the phase offsets of virtual controllers and tasks.

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