What Is EtherNet/IP? Industrial Ethernet Protocol Explained

What Is EtherNet/IP?

EtherNet/IP (Ethernet Industrial Protocol) is an industrial communication protocol developed by Allen-Bradley (now Rockwell Automation) and managed by ODVA. It uses standard 100 Mbps or 1 Gbps Ethernet hardware and the TCP/IP stack to carry CIP (Common Industrial Protocol) messages — the same application layer used by DeviceNet and ControlNet — over an Ethernet network.

How EtherNet/IP Works

EtherNet/IP uses two communication classes. Explicit Messaging uses TCP/IP for configuration, diagnostics, and non-time-critical data exchange. Implicit Messaging (I/O messaging) uses UDP/IP for real-time, cyclic data exchange between PLCs and field devices — similar to a cyclic I/O scan.

EtherNet/IP vs PROFINET vs Modbus TCP

Protocol	Developer	PLC Ecosystem
EtherNet/IP	Rockwell/ODVA	Allen-Bradley, Omron
PROFINET	Siemens/PI	Siemens S7, S1500
Modbus TCP	Modicon/Schneider	Universal, all vendors

EtherNet/IP and HMI Panels

Many industrial HMI panels, including selected Cermate models, support EtherNet/IP for direct connectivity to Allen-Bradley PLC systems without a protocol converter. Contact TSL Automation to confirm EtherNet/IP driver availability for your specific Cermate HMI model and Allen-Bradley PLC series.