Flexi-DNP3: Flexible distributed network protocol version 3 (DNP3) for SCADA security

Legacy SCADA systems are inherently insecure. They were built using specialized and proprietary protocols and used serial link, radio or leased line for communication. As these protocols were little known and specific to the industry they catered to, security was not important for them. But, recently because of increased terrorist attacks and migration of these protocols to TCP/IP, they have become susceptible to foreign attacks. We propose a mechanism to secure existing and future DNP3 networks. We built a BITW (bump - in - the - wire) prototype which exchanges keys and uses those keys to encrypt the data flowing on the network. We used DNPSec as our framework for BITW.

I. SCADA Systems

Supervisory Control and Data Acquisition (SCADA) systems are industrial control systems. Remote Terminal Units (RTUs) are connected to the Programmable Logic Controllers (PLCs). They are employed in many process industries including those of production, manufacturing, power generation, refining, fabrication etc. and infrastructure industries like water management, pipelines, power transmission and distribution, large communication systems etc.