Avaya S8700 Maintenance Manual page 1714

Maintenance-Object Repair Procedures
Maintenance/Far-End (MTC/FE)
This state is reached when the far end does not respond to messages sent
over the signaling link for a particular trunk after a certain amount of time.
This state is different from OOS/FE since the signaling link must have
initially been up and the B channels in service. The switch will periodically
send messages to the far end to try to negotiate the trunk (B channel) into
service. The trunk is unusable for outgoing calls but will service incoming
call requests from the far end. Note that transitions into MTC/FE do not
drop stable calls. Therefore, if the service state changes from in service to
MTC/FE, then stable calls are unaffected.
Maintenance/Near-End (MTC/NE)
The trunk (B channel) is in this state if the signaling channel (ISDN-LNK) is
busied out by system technician. The trunk (B channel) is also temporarily
in this state if the system technician has issued a test trunk
trunk-group/trunk-member long command. This command will execute
the ISDN-PRI test call. This test will change the state of the trunk member
to MTC/NE for the duration of the test unless a call request comes in from
the far end. In that case, the test would abort. Note that transitions into
MTC/NE do not drop stable calls. In this state, the B channel is not usable
for new incoming or outgoing calls.
Pending States
In addition to one of the previous components, the service state may have
a pending component, indicating that the switch is waiting for a reply from
the far end. These service states remain in effect until either a response is
received or the allotted waiting time expires.
— Pending-in-Service
— Pending-Maintenance
Call Activity States
The in-service state also has a call activity component.
— Active
— Idle
8-992 Issue 1 May 2002
The near end is awaiting a far-end response to a B-channel
maintenance message requesting that a B channel be transitioned
to in service.
This state is supported only by systems using country protocol 1
(including US). The near end is awaiting a far-end response to a
maintenance message requesting that a B channel be transitioned
to the maintenance service state.
A call is connected over the B channel (for example, in
serviceactive).
There is no call currently on the B channel (for example, in
serviceidle).
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