AT&T MERLIN LEGEND Release 3.1, System Programming Manual

Page: 505 / 887

PRI Facilities
Programming Procedures
4–133
Console Display/Instructions Additional Information PC
9 Save your entry.
Select
Enter Enter
.
0
10 Return to the System Programming menu.
Select
Exit Exit
two times.
55
B-Channel Groups
Use this procedure to perform the following:
■
Assign B-channels to a group.
■
Associate individual ISDN channels (that can place and receive calls) on
the B-channels in each group.
B-channels are partitioned into trunk groups when PRI service is ordered. The
trunk groups defined when service is ordered must match the B-channel groups
defined when MERLIN LEGEND is programmed.
Each B-channel can be assigned to only one group, and each ISDN channel can
be associated with only one group. Up to 80 B-channel groups can be
established.
Each group can contain up to 23 channels; however, all channels assigned must
signal through the same D-channel (that is, must be connected to the same
100D module).
B-channels must be assigned in the order of system search (through the group)
for an available channel. To minimize call attempts on the same line or trunk,
arrange B-channels in the opposite order of the hunting arrangement provided
by the network service provider.
B-channels must be identified by control unit slot and port numbers since they
are not associated with a line/trunk number or a logical ID.
PRI B-channel groups programmed for line routing perform similarly to loop-start
trunks. PRI B-channel groups programmed for dial plan routing perform similarly
to DID trunks.
NOTE:
If more lines than B-channels are assigned to a B-channel group, users may
experience situations where a line that is idle is not able to seize a B-channel.
The user will receive a fast busy tone.