IEC 62443-4-2:2019 provides detailed technical control system component requirements (CRs) associated with the seven foundational requirements (FRs) described in IEC TS 62443-1-1 including defining the requirements for control system capability security levels and their components, SL-C(component).
As defined in IEC TS 62443-1-1 there are a total of seven foundational requirements (FRs):
a) identification and authentication control (IAC),
b) use control (UC),