OPC-UA is the right answer for IT/OT integration in 2026. Here is how we actually bridge Siemens S7 and Beckhoff PLCs to a cloud stack.
Hungarian manufacturing is full of Siemens S7, Beckhoff TwinCAT, and Mitsubishi Q-series PLCs. Most of them still talk Modbus or a vendor protocol, but OPC-UA (IEC 62541) is the answer for modern IT/OT integration. This is the bridge architecture we actually ship.
One OPC-UA client runs on a gateway (x86 Linux or industrial Debian on Raspberry Pi 5), subscribes to the relevant nodes on each PLC, and forwards changes to a cloud MQTT broker. On the cloud, an ingest worker pulls from MQTT and writes into TimescaleDB continuous aggregates.
OPC-UA security is certificate-based. The default server config rejects unknown certificates. Provision the gateway client cert into the PLC's trusted store before connecting · otherwise you chase a silent 'connection refused' loop.
Not every integration needs cloud. A factory-floor SCADA with 500 tags runs fine on a small x86 NUC with TimescaleDB locally. Cloud becomes worthwhile when you cross sites or add ML on the data.
Founder, DField Solutions
I'm a full-stack engineer and I build across the whole stack myself · AI agents, web and mobile apps, blockchain, backends, security, right down to the OS layer. If it's software, I've probably built it and broken it.
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