ISDN Compatibility
372 ◆Features Aspire Software Manual
Primary Rate Interface (PRI)
The system is compatible with ISDN Primary Rate Interface (PRI) services. PRI services currently
supported include:
●Basic PRI Call Control (BCC)
●Display of incoming caller’s name and number when allowed by telco
●Routing in the system based on the number the caller dialed
●ISDN maintenance functions (such as In Service/Out of Service Messaging)
●Speech and 3.1 KHz audio
PRI capability requires the installation of T1/PRI Interface PCBs (0891009). Each PCB (also called a
PRI circuit) provides 24 PRI channels (23B + D) 1 with 64K Clear Channel response. The T1/PRI Inter-
face PCB uses a single slot.
When installed, the T1/PRI Interface PCB uses the first block of 24 consecutive trunks. For example, if
you have an 8COIU PCB installed for trunks 1-8, the T1/PRI Interface PCB will automatically use
trunks 9-32. If you have 8COIU PCBs installed for trunks 1-8 and 17-24, the T1/PRI PCB will use
trunks 25-48. The T1/PRI Interface cannot use trunks 9-16 (even if available) since they are not part of a
consecutive block of 24 trunks.
Trunk Number Translation for Channel ID Based on Trunk Group Number
The Channel ID of an incoming SETUP message on a PRI line is related to the trunk group number. The
system will create the trunk line number as the lowest trunk port number in the range of the same trunk
group related to the channel number of the Channel ID information element of an incoming call’s
SETUP message.
For example, referring to the chart below, the system translates the call as being trunk port 4.
Notes:
●In addition to T1/PRI Interface PCBs, PRI also requires a CSU/DSU Unit and interconnecting
cables to interface with the telco.
●Each T1/PRI Interface PCB is switch selectable between T1 and PRI operation. For more on
T1 Trunking, go to “T1 Trunking (with ANI/DNIS Compatibility)”.
1. Each T1/PRI Interface PCB provides 23 voice (B) and 1 data (D) channel.
Trunk
Number
Trunk
Group
Channel
Number
111
212
313
424
525
6 2 6 <--- Incoming Call
727
858
959
. . . 23 . . . 5 . . . 23