Testing of Security Enhanced DNP3 on Operational SCADA System

This paper presents results of testing and evaluation of security enhancements for SCADA communications applied to the SCADA protocol DNP3 on an actual SCADA system. Through collaboration with the Chemical Engineering Department, a functioning SCADA system that is used by the Unit Operations Laboratory course (CHE486) was made available during the 2007 spring semester. The test plan was to replace the current SCADA communication used by part of Unit Operations SCADA system with software modules that use security enhanced DNP3 protocols and observe potential impacts on system operation that may result from the modified protocols. Testing was carried out in conjunction with three Unit Operation labs. As part of each test actual SCADA network traffic was captured for offline analysis and evaluation. An important outcome was the collection of real network data for process control operations, as well as validation of the developed security enhancements, and experience with actual SCADA hardware and software controlling and monitoring a real process. Initial results indicate only a 14 % increase in the average bandwidth requirements using the challenge response mechanism, which would be acceptable for most SCADA installations. More importantly, no performance degradation was observed in the application, even at higher challenge frequencies.