Teaching reliable, secure and survivable Distributed Control System design

Abstract

Distributed Control Systems (DCS) are deployed in power utilities as well as communication, transportation, and financial infrastructures. As demonstrated by power distribution grid failures, most recently in August of 2003, designing for reliability is an important need. In addition to inherent design weaknesses, critical infrastructures are potential targets of cyber-terrorism and protecting critical infrastructures against terrorist attacks is a national priority. DCS security and survivability need increased attention. One of the Norwich University Electrical and Computer Engineering courses that address these issues is EE411 Microcomputer Based Applications. EE411 is designed to give computer and electrical engineering students a capstone DCS design experience applying concepts covered in earlier courses. They are introduced to "SCAD A ville", a municipal water system emulator modeled after a typical municipal water distribution system. The concepts of safety instrumentation and networking are introduced using Allen Bradley Programmable Logic Controllers (PLCs). Students come to understand the advantages and disadvantages of ladder logic code for digital controller reliability. In designing Distributed Control Systems that make any connection to the outside world, the system must withstand attack from disgruntled employees, hackers or cyber terrorists. The system must function well even when the attacker breaks through the security barrier. In the EE411 course, the concepts of redundancy, robustness, and resilience are developed and reinforced in the laboratories.