The even configuration object are defined and associated with an Object in the Server AddressSpace, this assumes the server is the source of the event. Additional section or text should be added to describe how a historian that is subscribing for events from some external source should indicate the configuration associated with that external source. this may require defining an object that represents the external event source.

This section might also want to describe a historian that exposes an object tree with historical event, where the tree is mirrored from an underlining system that actually generate the events (received via OPC UA).
[note: if the event are received from an underlying system, but the corresponding object are also in the AddressSpace no special configuration would be required]