Avaya Nortel Communication Server 1000 Reference page 448

NT8D15 E and M Trunk card
Duplex signaling
Duplex (DX) signaling makes use of the voice transmission leads for signaling as well as for
voice transmission.
For descriptive purposes, the lead pair Tip B/Ring B is designated the signaling pair. The other
pair Tip A/Ring A conducts current in the opposite direction to balance the overall current flow
between the near and far ends. During signaling, current flows through both Tip B and Ring B
leads in the same direction.
Table 183: DX signaling - outgoing calls with originating party release
184: DX signaling - incoming calls with originating party release
connection and take-down sequencing for DX signaling.
calls with originating party release on tandem connections
signaling - incoming calls with originating party release on tandem connections
show sequencing where the E and M Trunk card is used in a tandem PBX.
Table 183: DX signaling - outgoing calls with originating party release
Idle
Seizure (dial tone from far-end: far-end ready
for digits)
Digits
Far-end answers
Far-end on hook first
Network taken down and trunk idled when
near-end goes on hook
Near-end on hook first, network taken down Current flow
Far-end on hook, trunk idled
Table 184: DX signaling - incoming calls with originating party release
Idle
Seizure (dial tone to far-end: near-end ready
for digits)
448 Circuit Card Reference
Condition
Condition
Comments? infodev@avaya.com
Table 185: DX signaling - outgoing
on page 449 and
Current in signaling
lead
No current flow High
Current flow High
Current flow High
interrupted for each
pulse
No current flow Low
Current flow High
No current flow High
Low
No current flow High
Current in signaling
lead
No current flow High
Current flow Low
on page 448 and
on page 448 show call-
Table 186: DX
on page 450
State of trunk
detector
State of trunk
detector
July 2011
Table