User manual
DEFINITY ECS Release 8.2 Maintenance for R8.2csi 
555-233-119  Issue 1
April 2000
Maintenance Objects 
3-737ISDN-TRK (DS1 ISDN Trunk) 
3
The trunk is unusable for outgoing calls. On US interfaces, the trunk is 
unusable for incoming calls, but on non-US interfaces, incoming calls will 
be accepted.
■ Out-of-Service/Near-end (OOS/NE)
This is the state of the trunk when a hardware failure exists on the link, the 
NPE Crosstalk Test fails, or when the trunk is busied out by system 
technician. In this state, the trunk is unusable for incoming or outgoing 
calls. No messages are sent to the far-end until the signaling link comes 
back into service or the trunk is released by system technician.
■ 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 link (PKT-INT) is 
busied out by system technician. The trunk (B-channel) is also temporarily 
in this state if 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. Therefore, a system technician- 
demanded 
busyout link lnk-no
 command will not drop stable trunk calls. 
In this state, the B-channel is not usable for new outgoing calls, but is 
available for incoming calls and outgoing test calls.
■ Pending States 
If the near-end is expecting a timed response from the far-end for a 
request to change the service state of a trunk, then the state of the trunk 
reflects a Pending State.
— Pending-in-service (PINS)
The near-end has sent a B-channel maintenance message to the 
far-end, requesting that the B-channel service state be transitioned 
to in-service. The far-end has a certain amount of time to respond to 
the message. The service state will be PINS until either a response 
is received or the timer expires.










