The PublisherId is a unique identifier for a Publisherwithin a Message Oriented Middleware. It can be included in sent NetworkMessagefor identification or filtering. The value of the PublisherIdis typically shared between PubSubConnectionsbut the assignment of the PublisherIdis vendor specific.

The PublisherIdparameter is only relevant for the Publisherfunctionality inside a PubSubConnection. The filter setting on the Subscriberside is contained in the DataSetReaderparameters.

Valid DataTypesare UIntegerand String. A zero UIntegerand a Null or empty Stringare invalid PublisherIds.

The unique identifier for an OPC UA Applicationis the ApplicationUri. It is recommended to use the ApplicationUri Stringas a default PublisherIdfor broker based transport protocols.

The default PublisherIdfor datagram transport protocols has a DataTypeof UInt64. If the default PublisherIdis created by the OPC UA Application, it is recommended to set the first 6 bytes with the MAC address of one of the network interfaces and to set the two remaining bytes to the OPC UA Serverport of the OPC UA Application.

The default PublisherIdis used if it is not assigned by a configuration tool.