Year
2023
File Attachment
finalpaper_260_0512074841.pdf668.77 KB
Abstract
With the increasing adoption of digital instrument and control systems in nuclear facilities,
cyber-attacks pose serious threats and bring a new issue to nuclear security. In response,
authorities have published relevant criteria for preventing cyber-attacks in security culture and
recommended to adopt Defense in Depth (DiD) strategy to cyber-security of nuclear facilities.
To this end, we introduce deep learning-based time series analysis to detect cyber-attacks on
nuclear facilities. Given the difficulty of deep learning models training due to the lack of cyberattacks data on nuclear facilities, we design a virtual cyber physical system (CPS) to simulate
cyber-attacks and generate cyber-attack datasets. The virtual CPS deploys the human machine
interface (HMI), programmable logic controller (PLC) and controlled devices connected via
Modbus/TCP protocol to simulate the control processes in nuclear facilities. The simulation of
cyber-attacks consists of two steps carried out separately on two independent Local Area
Networks (LANs), i.e., site LAN #1, site LAN #2. In cyber-attacks, hackers obtain access to
office computers in NPPs through site LAN #1 by buffer overflow attack and collect network
traffic data on the attacked host. Then, we simulate hackers using the attacked host to attack the
PLC through site LAN #2 to cause confusions collect network traffic data on the attacked PLC
device to generate the first part of the dataset. This simulation imitates a real cyber-attack
activity that could happen in nuclear facilities. And we also collect the data of the device status
simultaneously to monitor the physical layer condition. To demonstrate the practicality of the
generated datasets, verification experiments are performed on the proposed deep learning
model. Moreover, the design of virtual CPS allows flexible generation of extensive cyberattacks datasets, which has significant benefits for further evaluation of the design of cyber
security systems for nuclear facilities and the implementation of DiD.