- Posted by fedco
- On January 4, 2015
- ics security reference model, iec 62443, security reference model
ICS Reference Model – IEC 62443-1
The term of reference model became popular in IT world since the introduction of Open Systems Interconnection (OSI) model. The OSI model split the layers of communication into 7 layers. A couple period after the introduction of OSI model, the Transport Control Protocol/Internet Protocol (TCP/IP) model also introduced to the public with the more simple layer segregation, it is only consist 4 layers.
Refer to U.S. NASA Office of Standards and Technology (NOST), the “reference model” is defined as:
“A reference model is a framework for understanding significant relationships among the entities of some environment, and for the development of consistent standards or specifications supporting that environment. A reference model is based on a small number of unifying concepts and may be used as a basis for education and explaining standards to a non-specialist.”
From the Industrial Control System point of view, a reference model describes a generic view of an integrated manufacturing or production system, expressed as a series of logical levels. IEC 62443 reference model adopting the segregation layers principle, with 5 layers in total that describe the fundamental categorisation based on the functionality, interconnectivity, nature of operations and integrative approach. Following is the IEC 62443 reference model for the Industrial Control System environment including the correlation with the enterprise network,
The proper layer segregation management as per shown in the above diagram can help the organisation to leverage their operations management performance and security assurance.
A similar reference model for SCADA specific system can also derived from the above diagram, following is the reference model,