Media Connection Preservation maintains calls that experience end-to-end signalling loss or refresh failures but that still have an active media path.
IP Phones
With IP Office 9.1 and higher, the following Avaya IP phones attempt to maintain calls when the signal from the host IP Office is lost.
9608
9611
9621
9641
J100 Series
When preserving a call, the phone does not attempt to reregister with their call server or attempt to failover to a standby call server, until the call has ended. Softkey call actions and feature menus do not work during this time due to the loss of signalling path. The phone display is not updated and the only permitted action is to terminate the call.
IP Office
When enabled for a particular IP endpoint type that supports Media Connection Preservation, the call is put into a Preserved state and a Preservation Interval timer is started for that call at the point the signalling loss is detected. The maximum duration of a preserved call on IP Office is two hours. Once put into the Preserved state, a call can only transition to the Terminated state. Call restoration is not supported.
Only the following call types are preserved:
Connected active calls
Two party calls where the other end is a phone, trunk, or voicemail
Conference calls
Calls on hold and calls to hunt groups are not preserved.
Phone Display
When a call is in a preserved state but the phone's local signalling connection with its host IP Office is still present, the phone call state display is prefixed with a warning icon. Hold, transfer, and conference actions are not available.
