AiVibeOPC UA PubSub
OPC UA PubSub is the publish-subscribe communication model defined in Part 14 of the OPC UA specification, letting publishers send OPC UA data to many subscribers through brokers or directly over the network without client-server sessions.
In PubSub, a publisher groups selected variables into data sets and sends them as network messages at configured intervals. Two families of transport are defined: broker-less communication over UDP multicast or Ethernet, suited to fast, deterministic exchange on local networks, and broker-based communication over MQTT or AMQP, suited to cloud and enterprise integration. Messages can be encoded in the compact binary UADP format or in JSON, and the same information models as client-server OPC UA describe the data.
PubSub addresses scenarios that client-server OPC UA handles less efficiently: one-to-many distribution, controller-to-controller communication and sending data to cloud services through message brokers. Combined with Time-Sensitive Networking, it forms the basis of the OPC Foundation's field level communications work, which aims at deterministic, vendor-independent communication down to field devices.
Security for PubSub uses message signing and encryption with keys distributed by a security key service, while broker-based transports also rely on the broker's TLS and access controls. Engineers must configure publishing intervals, data set metadata and how subscribers learn message layouts. Support differs between products, so interoperability should be checked for the specific transports and encodings in use.
Key points
- Defined in Part 14 of the OPC UA specification
- Broker-less transports: UDP multicast and Ethernet
- Broker-based transports: MQTT and AMQP
- Encodings include binary UADP and JSON
- Combined with TSN for deterministic field-level communication
Where AiVibe comes in
AiAmbA IoT is AiVibe's edge protocol layer: it discovers devices and normalises industrial signals, with supported protocols including Siemens S7, Mitsubishi MC, Delta Modbus, OPC UA and MQTT, and driver availability confirmed per installation. Writes to machines are deny-by-default.
Related terms
- OPC Unified Architecture (OPC UA)Industrial IoT & Edge
- MQTTIndustrial IoT & Edge
- Time-Sensitive Networking (TSN)Industrial IoT & Edge
- MQTT BrokerIndustrial IoT & Edge
- Unified Namespace (UNS)Industrial IoT & Edge