This text string names the node or entity that an OpenView event is about, which may differ from the machine that actually transmitted the trap. It is used by OpenView software to tell the receiving management station which managed node the alert concerns, even when the trap itself is sent by a central management station rather than the node directly. For example, this field might read "router-core1.example.com" even though the trap was actually emitted by the OpenView management server monitoring that router.