Specifications

Reference Guide
2-15
Applications Data Modules and Applications
All three remote loop backs are latching loop backs. These latching loop backs are:
•
loop back of the analog interface of the remote OCU-DP device back towards the
network
•
loop back of the 4-wire interface of the remote CSU device back towards the network
•
loop backs of the 4-wire interface of the local CSU device towards the network.
An OCU-DP port may be programmed to detect and respond to both latching and non-latching
(i.e., alternating) DDS-format OCU loop back codes that are initiated from the remote end of
the circuit. A time-out option authorizes the OCU-DP port to automatically release the loop
back after ten minutes.
2.4.6 BRI Card
The 826x line of BRI Cards offers industry standard ISDN BRI “U” or “S/T” Interfaces. Each
BRI Card supports eight BRI “U” Interfaces for long line circuit provisioning, or “S/T”
Interface for local provisioning. The BRI Interface provides two bearer and one data channel
over two wires (1 pair). The S/T interface provides the same functionality over 4 wires (2
pair). In addition to this, each BRI “U” Interface supports 256x NTUs, providing remote NTU
management.
The Basic Rate Interface “U” Interface card offers connectivity to sites located up to 18,000
feet from the integrated access system. This distance is influenced by factors such as wire
gauge, bridge tap and loading patterns as described in ANSI T1.601-1992 specifications. The
BRI cards are equipped with eight “U” interfaces that can carry one BRI, 2B+D channel. This
will give users either two 64 Kbps or one 128 Kbps bearer channels per interface. The “U”
Interface is also provides optional sealing current for maintaining wire pair performance.
When used with WAN and Server Card options, the BRI card facilitates BRITE (BRI Terminal
Extension), leased line or IDSL (2B1Q) Provisioning, BRI to PRI operation and BRI (data) to
Frame Relay Operation.
BRITE allows the Integrated Access System to extend the reach of an ISDN PBX hundred of
miles away from the location of the PBX switch as shown in Figure 2-7. All services are
passed to the remote location with no restrictions, enabling the end user or agent to use all
PBX functionality as if they were locally attached to the switch. Management of this solution
is transparent to the PBX programmer. All remote extensions are treated as if they are local
connections. No special programming or management is necessary. For example, if there was
an ISDN switch located in Los Angeles, ISDN capabilities could be transparently transported
across the network to a remote call center in New York.