What is the architecture used by Modbus?

Modbus primarily uses a Master-Slave architecture, which is characterized by a single master device communicating with one or more slave devices. In this setup, the master initiates requests to the slaves, which respond with the requested information. This architecture is straightforward and enables efficient communication in industrial environments, particularly for monitoring and controlling devices such as sensors, actuators, and controllers.

The reason the Master-Slave architecture is effective is that it allows for centralized control, where the master device orchestrates the data flow and manages operations among multiple slaves. This structure also simplifies the design and implementation of systems that require reliable command and control in industrial settings.

While other architectures like Client-Server may be utilized in different contexts, they do not accurately represent the communication model of Modbus. The Client-Server model involves a request-response mechanism where multiple clients can send requests to a server, which can complicate the communication compared to the direct nature of Master-Slave interactions.