Digital twin
A DT is a virtual copy of an IoT device that’s deployed in the field. The concept is very similar to the process of creating a model (simulation) of a physical entity or process to understand its exhibited behavior. The notation for DT used in this book is shown in the following figure:
Figure 2.3 – Notation for the DT pattern
DT is an important pattern in the context of IoT as data may be transferred between the central server and field devices over unreliable communication channels (intermittent connectivity). Also, field devices may choose to sleep and only wake up during specific times to conserve energy. So, DT is also used to abstract users from the current state of field devices (wake up, sleep, and so on) and the communication channel’s nuances.
DT also provides an encapsulation mechanism whereby users can view and set the state without being concerned with the actual state of the field devices and/or connectivity...