SCADA, or Supervisory Control and Data Acquisition, is a type of industrial control system that centrally manages physical equipment by sending commands and collecting real-time data from sensors and controllers on the floor. Understanding its core components and communication protocols is foundational to securing operational technology environments.
SCADA Systems
One of our industrial control systems possibly is a supervisory control and data acquisition, or SCADA, system.
Let's look at a scenario. Let's look at an assembly line for cars. This car is going through the assembly line and it's getting assembled. At one point in time, just humans did that, right? When Ford created the assembly line for his Ford motor vehicles, what would happen is they would go across this assembly line and different people would put different parts on.
But over time, those got replaced by robots. These robots initially were autonomous. That is, one robot didn't necessarily affect another robot, and there was no overcontrolling aspect of these different robots. Instead, they were just in charge of, for instance, maybe this robot right here was putting on a tire and this robot right here was putting on the top, and they were doing different aspects of creating this vehicle. Maybe there were some sensors associated with these individual robots that were assembling it together, but essentially what they did is they all acted individually.
This created a problem, though, because sometimes what one did or discovered might affect what another one would do. So to a certain degree you want a little more control, that is able to control these different robots, so you want to somehow centralize control of this.
This is where the supervisory control and data acquisition, or SCADA, comes in, because there are two aspects to this. It's supervisory control, so it's control of these robots. That's kind of one direction here, where it sends commands to manipulate and control each one of these robots. But the other part of this is data acquisition. For it to really make decisions, what it needs to do is receive information as well. So there's a two-way street here, where it does data acquisition by acquiring data from these robots and then making decisions, so it can give better instructions down the assembly line.
There are several core components of a SCADA system. You've got the computer or server and the software that's running on it that's doing all the controlling. Of course, it needs to communicate back and forth, so you have some sort of networking or protocols that are being used to carry out this communication. You've got sensors to understand what's going on, and you've got controllers to then deliver whatever instructions need to be delivered to the equipment.
Here we have SCADA. SCADA is going to be this system right here. It's servers that are running, so we've got a hardware component, and software that's running on top of it, so we've got a software component. They're now talking to these devices right here. So we've got the acquisition part of this, where it's receiving information, sensors, making decisions, and then delivering controlling, that's the controlling part of this. So supervisory control is sending the information, and the data acquisition is receiving that information. We've got protocols running to help this communication.
Another part of this system is RTUs or PLCs. What these SCADA systems do is they need to send instructions and receive data from something that's on the floor. Well, one of the things that's on the floor is either an RTU or a PLC. We're not going to get real in depth into that right now, but just know that these are systems that are running on the floor that are delivering instructions to the actual end devices and controlling those.
I thought we could pull up the wiki article and just talk about some of those communication protocols. Here are some of the communication protocols that work with these industrial control systems, some of the protocols that help facilitate this communication. You can see there's a ton of them, depending on what it is that we're trying to do.
So there are quite a few different protocols that are used for this communication that goes back and forth.
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