Applying a Verified Trusted Computing Base to Cyber Protect a Vulnerable Traffic Control Cyber-Physical System

Abstract

Traffic control systems were developed with operational performance, reliability, and safety in mind. Traffic control systems were designed well before the heavy integration of advanced communications including radio frequency (RF), the Internet and cellular transmissions. These technologies were integrated to provide more control and enable the traffic systems to become adaptive to real-time traffic flow and environmental conditions. These advances increase the opportunity for attackers to affect traffic system operations, sometimes creating a congestion which essentially halts traffic. The Secure SCADA Framework presents eight objectives which would increase the cyber resilience of an existing vulnerable cyber physical system, such as a traffic control system [1]. This approach retains the current operational performance, reliability, and safety. The concept of using a Trusted Computing Base (TCB) in a cyber-physical system is one goal of the eight presented for the Secure SCADA Framework. The SCADA TCB (STCB) project designs, develops, and verifies a core set of hardware, software, and firmware which operate in conjunction to establish a high level of security protecting a traffic control system. This research defines the requirements of a traffic control system, establishes a security policy, develops a trusted computing base, identifies and designs attacks on the system, and meets the development life-cycle requirements to proceed with implementation, verification, and testing.