ISDN-TRK (DS1 ISDN Trunk)
Issue 5 October 2002
1303
555-233-119
ISDN-TRK (DS1 ISDN Trunk)
A DS1 ISDN Trunk is known as a B-channel. It is a 64 kbps Bearer channel that
can be used to transmit digital traffic, be it voice or data. These trunks use a
separate channel for signaling (for example, for call setup); this mode of operation
is known as out-of-band signaling, as opposed to in-band, robbed-bit signaling,
where the signaling traffic flows over the same channel as the voice or data traffic.
The separate signaling channel is called a D-channel in ISDN terminology, and it
carries all the call control signaling messages for the DS1 ISDN Trunk
B-channels. The D-channel for these B-channels is an ISDN-PRI (Primary Rate
Interface) Signaling Link Port (ISDN-LNK/ISDN-PLK).
On 24-channel interfaces, any of the first 23 ports on the DS1/UDS1 interface
circuit pack can be a B-channel. The 24th port may be used as a B-channel or as
a D-channel depending on the type of ISDN-PRI Signaling Group (ISDN-SGR) to
which it belongs.
MO Name (in
Alarm Log)
Alarm Level
Initial Command to
Run
Full Name of MO
ISDN-TRK
1
1.
For additional repair information, refer to the “DS1-BD (DS1 Interface Circuit Pack)”
maintenance object.
MAJOR
2
2.
A MAJOR alarm on a trunk indicates that alarms on these trunks are not downgraded
by the set options command and that at least 75 percent of the trunks in this trunk
group are alarmed.
test port PCSSpp l
DS1 ISDN Trunk
ISDN-TRK
MINOR
test port PCSSpp l
DS1 ISDN Trunk
ISDN-TRK
WARNING
test port PCSSpp sh
DS1 ISDN Trunk