OPC-UA is a network-based specification, and is ideal for collecting data from remote locations. Ignition can operate as an OPC I/O server with just the OPC-UA Module and UA drivers installed. Other OPC-UA client software can then access the PLC data through Ignition.

This method only exposes data, however, and the Client must then record it if historical data is desired. If the connection goes down, data will not be available. This method offers the lowest cost, and is suited for situations where the data is not highly critical or historical, for example, remote realtime monitoring.