This specification provides the possibility to indicate changes in the AddressSpace to a client. Most often this concept is used in list representations, to add or delete Nodesfrom the list. OPC 10000-3defines the property NodeVersionand the GeneralModelChangeEventTypeto indicate such changes. Whenever the address space in this specification is changing, the NodeVersionand the GeneralModelChangeEventshall be used in the way defined in OPC 10000-3.

As content for the NodeVersion Property, a timestamp of the moment the node structure was changed converted to a string with the format yyyy-MM-ddTHH:mm:ss.sZ (using UTC time for display) shall be used.