OPC UA is one of several protocols used in industrial communication, and it’s often deployed alongside, or compared to, others. This section outlines the most common alternative and complementary protocols you’re likely to encounter.
| Term | Definition |
|---|---|
| Modbus | A serial and Ethernet-based communications protocol originally developed for programmable logic controllers, now widely supported across industrial devices. |
| EtherNet/IP | An industrial Ethernet network protocol that adapts the Common Industrial Protocol (CIP) for use over standard Ethernet. |
| PROFIBUS | A fieldbus communication standard widely used in process and factory automation for connecting controllers to field devices. |
| PROFINET | An industrial Ethernet standard, the successor to PROFIBUS, designed for real-time communication between controllers and field devices. |
| BACnet | A data communication protocol developed for building automation and control systems, such as HVAC, lighting, and access control. |
| DNP3 (Distributed Network Protocol) | A communications protocol widely used in SCADA systems, particularly in the electric and water utility sectors. |
| MQTT (Message Queuing Telemetry Transport) | A lightweight publish-subscribe messaging protocol designed for constrained devices and low-bandwidth, high-latency networks. |
| AMQP (Advanced Message Queuing Protocol) | An open messaging protocol that supports message queuing, routing, and reliable delivery between applications. |
| SNMP (Simple Network Management Protocol) | A protocol used to monitor and manage network devices, commonly used to oversee IT infrastructure health in industrial networks. |
| GPRS (General Packet Radio Service) | A packet-based wireless data service used to transmit data over cellular networks, often used for remote RTU telemetry. |
| LonWorks | A networking platform designed for control applications, historically popular for building automation functions such as lighting and HVAC. |