Trusted Industrial Modbus Firewall for Critical Infrastructure Systems

Abstract

Cyber-attacks on critical infrastructure, industrial systems such as SCADA (Supervisory Control and Data Acquisition), have become ambitious over the past years, where a successful execution could lead to dangerous real world consequences such as power outages and expensive pieces of equipment receiving permanent damage. Additionally, the recently popular “Industry 4.0” trend brings Internet connectivity to sensitive industrial machinery, requesting improved cyber security practices to offset the extended attack surface. We present an affordable, realtime hardware firewall solution for securely isolating the cyber-physical devices from the untrusted, Internet facing networks, while still being able to remotely control them from trusted devices. We take on the insecure Modbus protocol and enhance it to ensure an authenticated industrial communication channel while keeping its strict latency requirements satistifed. Our architecture employs the Trusted Execution Technologies available on modern PCs such that operators will able to securely monitor and control their critical equipment from anywhere on the Internet, proposing a careful approach on the new industrial revolution.