With this option, OPC UA PubSub relies on the network infrastructure to deliver NetworkMessages to one or more receivers. Network devices – like network routers, switches, or bridges – are typically used for this purpose.

One example is a switched network and the use of UDP with unicast or multicast messages shown in Figure 13.

Figure 13 – PubSub using network infrastructure

Advantages of this model include:

• Only requires standard network equipment and no additional software components like a Broker.
• Message delivery is assumed to be direct without software intermediaries and therefore provides reduced latency and overhead.
• UDP protocol supports multiple subscribers using multicast addressing.