The Internet of Things architecture can be viewed as a collection of various levels of abstraction. A layer covers up a subsystem's details of the implementation, enabling the separation of concerns. To rephrase it in another way, a layer is only aware of its sub-layer. In an IoT system, information is passed from one layer to the next.
The functional requirement for each IoT system may differ depending on the challenge or task assigned to it. Many attempts have been made to use layers to model an IoT architecture.
3 Layer Architecture
5 Layer Architecture
7 Layer Architecture