OutOfServiceEvent
This event is triggered when a SIP phone unregisters and the device is out of service.
OutOfServiceEvent
<OutOfServiceEvent xmlns="http://www.ecma.ch/standards/ecma-323/csta/ed6">
<monitorCrossRefID>u-12345678-200</monitorCrossRefID>
<device>
<deviceIdentifier>200</deviceIdentifier>
</device>
</OutOfServiceEvent>