Meaning
Messaging protocols allow for the distribution of industrial data from a single source to multiple subscribers without direct point-to-point connections. Implementing opc ua pubsub facilitates the integration of large scale sensor networks into cloud based analytics platforms. This architecture decouples the data producer from the consumer to improve network efficiency.
It is used in systems where the traditional client-server model would create too much overhead.
Messaging Architecture
Data is published to a common broker or a multicast address rather than being sent to each recipient individually. Each subscriber listens for the specific topics or data sets they require for their function. This reduces the load on the controller because it only needs to send the message once regardless of how many systems are reading it.
Scalability Benefit
Adding a new dashboard or an archive service does not require any changes to the original data source. The new system simply subscribes to the existing stream of information coming from the opc ua pubsub publisher. This makes it easier to expand the monitoring capabilities of a factory without risking the stability of the control network.
Transport Layer
Real time performance is achieved by using low overhead protocols like mqtt or udp for the actual data transfer. The standard defines how the data is formatted so that any compliant device can understand it. This interoperability is necessary for building heterogeneous systems that include equipment from multiple vendors.
