What Is PROFINET?
PROFINET — short for Process Field Network — is an open Industrial Ethernet protocol for exchanging data between controllers and field devices in automation environments. Developed by PROFIBUS & PROFINET International (PI) and launched in 2001, it integrates real-time communication, distributed I/O, and seamless integration with existing fieldbus systems.
Controllers are typically PLCs, DCSs, or PACs, while devices can include I/O blocks, vision systems, RFID readers, drives, and process instruments. Profinet It is the most widely adopted industrial Ethernet protocol in use today.
How Does It Work?
PROFINET sits at Layer 7 of the OSI model and uses standard Ethernet cabling Profinet, but offers multiple communication channels depending on how time-sensitive the data is:
- Non-Real-Time (TCP/IP) — for configuration, parameterisation, and diagnostics.
- RT (Real-Time) — bypasses the TCP/IP stack using a dedicated EtherType for deterministic, low-latency control data.
- IRT (Isochronous Real-Time) — achieves cycle times as low as 31.25 µs with jitter of just 1 µs Profinet, used in motion control and high-speed machinery.
- Over TSN — combines PROFINET with Time-Sensitive Networking for convergence of multiple protocols on a single infrastructure.
Because it runs on standard Ethernet, other protocols such as OPC UA, MQTT, and HTTP can coexist on the same network.
Why It Matters for Industrial Connectivity
PROFINET handles real-time communication at the machine level, but connecting those systems remotely — for monitoring, SCADA access, or cloud integration — requires reliable WAN connectivity. Industrial routers, managed switches with PROFINET support (such as the Teltonika TSW range available from Millbeck), and IoT SIM cards bridge that gap, keeping your automation infrastructure accessible and secure from anywhere.