There is a correlation between ModelChangeEventsand the NodeVersion Property of Nodes. Every time a ModelChangeEventis issued for a Node, its NodeVersionshall be changed, and every time the NodeVersionis changed, a ModelChangeEventshall be generated. A Servershall support both the ModelChangeEventand the NodeVersion Propertyor neither, but never only one of the two mechanisms.

This relation also implies that only those Nodesof the AddressSpacehaving a NodeVersionshall trigger a ModelChangeEvent. Other Nodesshall not trigger a ModelChangeEvent.