So how does all this tie together? What makes for a solid ICS architecture? To answer this question, we should first discuss the Purdue reference model, or Purdue model for short. As shown in the following figure, Purdue model was adopted from the Purdue Enterprise Reference Architecture (PERA) model by ISA-99 and used as a concept model for ICS network segmentation. It is an industry adopted reference model that shows the interconnections and interdependencies of all the main components of a typical ICS.
The model is a great resource to start the process of figuring out a typical modern ICS architecture:
The Purdue model will be discussed in more detail in a later chapter, but for now, to ...
