While evaluating the practical applicability of IT-based authentication and authorization techniques for IIoT use cases, it is important that we keep in perspective the unique demands of the cyber-physical world (discussed in the Distinguishing features of IAM for IIoT section).
Note: This section and all subsequent sections of this chapter assume that the reader has a basic familiarity with modern cryptography.
Figure 3.2 summarizes the three main approaches of authentication:
Figure 3.2: Examples of authentication factors
