As we work to define the cybersecurity of things, power demands its own security models, outside of SCADA security and distributed controls. Power is both a resource and a vector, and each of these offers vulnerabilities to cyberattack. This article describes cybersecurity of the resource. A later article will discuss cybersecurity of the vector.
Distributed cybersecurity is a model that distributes responsibility across autonomous nodes or systems. These nodes may send or receive cybersecurity directives. They may request or share situation awareness. Each node is responsible for securing itself and reporting when it is under attack.
The developing OASIS OpenC2 (Open Command & Control) specification defines cybersecurity as a service. The sender of a command requests what it wants accomplished without using step-by-step instructions. If the receiver accepts the command it must determine and execute its own procedure to fulfill that request.
As a resource, a power system must defend certain characteristics. These characteristics include frequency, voltage, and the shape of the waveform itself. Cyberattacks on the power resource can interfere with proper system operation or they can escalate into direct cyberphysical effects. The well-known Aurora demonstration by DHS used repeated subtle waveform manipulation, to cause a large dynamo to rip itself out of its concrete moorings. Any cyberprocess that is able to manipulate the fundamental power signal can be an effective attack on the Internet of Things.
When a distributed cybersecurity language such as OpenC2 shares information about an attack through the power vector, it may act as a warning, or it may describe what the requestor wants reported back. Because Power is likely shared between many nodes on the same circuit, anything that has a strong effect on one node, perhaps low-value and poorly defended, can be a means to attack other nodes on the same circuit. I know of substations in the Midwest, supplying a limited number of industrial customers, wherein the operating margin is so small that activity in one factory can cause and has caused significant damage to equipment in another factory. Situation awareness coming back from one node may be useful to gain a broader understanding of attacks on other nodes.
Attacks on power through a nearby un-protected node can cause damage to all nodes on the same circuit. A large user can cause changes to voltage, to power factor, or to other power attributes even without the subtle wave harmonics demonstrated in Aurora. They may even cause delayed effects, as a sustained reduction in power factor may prevent power storage systems from re-charging properly over several days. As tomorrow’s grid incorporates a growing number of renewables, this offers a growing vulnerability.
Because they are working sharing a resource, a cyber-response may help defend nearby nodes. If a node is able to actively manage frequency or power factor, it may defend nearby resources.
I will write soon on Power Distribution as a Cybersecurity Vector.