Call States (Trunk)

State	Trunk
Idle	There is no call or call attempt on this port or channel.
Out of Service	The port has been set out of service or the digital circuit (that this channel is on) is down.
Connected	The port has a connected call.
Connected WAN	This time slot in use to deliver WAN interface - digital trunks only.
Parked	The system or a user has parked the call.
Seized	The system has seized the line in preparation to make a call.
Dialling	The system has seized the line and dialed out digits but the call is not yet connected.
Clearing	The call is in the process of terminating or is in post call wrap-up.
Pre-Alert	The system has received an incoming on the trunk. The system is waiting for Caller ID.
Outgoing Alerting	The system has made an outgoing call on the trunk, The far end is alerting.
Incoming Alerting	The system has presented the incoming to a target at which it is alerting or queued.
Paging	Indicates one or more output points of a paging call.
Recording	The system is using the call record another call.
Held at Central Office	For European ISDN lines, the central office has the call on hold. It frees the B-channel which returns to idle in System Status.
Holding	Indicates that the other party on the call is in one of the Held states: Held, Held for Transfer, Held for Conference, Held at Central Office, Hold Reminder.
Connected Blind	Indicates that this end of the call is connected and that the other party on the call is alerting with either a blind transferred call or a transfer return.
Queuing	Indicates that the system has queued the call for a hunt group. While queued, the call does not alert at any extension.
Alerting Announcement	Indicates that the call is alerting at one or more extensions or trunks and also currently connected to voicemail for a queuing announcement.
Queuing Announcement	Indicates a queued call connected to voicemail for a queuing announcement.
Connected Announcement	Indicates a connected call listening to a queuing announcement.

When a call is alerting, one end is in the alerting state while the other is in the ringback state. From the view of the system, Ringback and Incoming Alerting are equivalent states. Similarly, Alerting and Outgoing Alerting are equivalent states.

The Trunk Summary and Extension Status screens show the direction of each call. Trunks show the as outgoing if the system initiated the call and incoming if the central office or network initiated the call. Extensions show the call as outgoing if the extension initiated the call and incoming if another party initiated the call.