What was that Purdue Model stuff, anyway?

The Purdue Enterprise Reference Architecture (commonly known as the Purdue Model) for control systems is old. People have forgotten what it originally was about. When it was first introduced, the big concern behind the Purdue Model was keeping computing and networks deterministic so that they wouldn’t fault. Toward that end, it introduced network segmentation as […]

Complex control systems used by ships at sea are subject to the same kinds of accidents and challenges.

“This is where you talk about fleets coming to a stop. Our ships are floating SCADA systems” – Capt. Mark Hagerott (ret.), Deputy director of cybersecurity for the U.S.N. Academy (1) Many years ago I had the good fortune to have two good friends who both owned wooden (African Mahogany) sailing boats. One was a […]

Security Breach Detection

When I see most OT staff discuss ICS security, they usually begin with some networking gewgaws and tweaks. This sort of stuff is interesting the first few times going through this exercise. However, it doesn’t take long to realize that network security alone is a multi-headed hydra of a problem. The more we try and […]

Assigning Responsibility for ICS Security

Once the pain of a risk assessment is over, a few managers look at each other and decide on what changes they would like to make. Usually an IT expert comes in to install new network security hardware or someone is tasked with revising documentation; but rarely does anyone tinker with assigning responsibility. Nobody wants […]

How A Process Works

Understanding Industrial Process Control Buried among the design blue prints and volumes of handbooks, there are two documents of great significance to anyone who cares about ICS security. The names may be slightly different than what I’m calling them here, but the concept is the same. First is the Process Description. It is an overview […]