- Paradyne Network Device Product Manual

Zhone Technologies, Inc. IMACS Product Book, Version 4
March 2001 Page 72
Applications
The ISDN PRI Server card can be used in a variety of applications:
Fractional ISDN PRI provisioning
Video conferencing
Integrated ISDN access with SINA
Video Broadcast
Router with redundant trunk routing via ISDN
Router adding incremental bandwidth
PRI to FXS
Fractional PRI Provisioning
An IMACS equipped with a 8840C PRI Server card is used to groom multiple fractional PRI circuits into one or
more PRI circuits for backhaul to an ISDN switch. Perhaps a customer may not need the entire bandwidth delivered
by a PRI circuit. The optimal alternative would be to purchase a fractional PRI service delivered over a regular T1
or E1 circuit. When a service provider has multiple fractional PRI customers, the service provider can deploy the
IMACS to groom the multiple fractional PRI circuits into one fully utilized PRI T1/E1 circuit, which is back hauled
to the switch. This concentration of PRI circuits reduced back haul costs for the service provider, and conserves
T1/E1 ports and D-channels on the ISDN switch itself.
Figure 23 shows that three customers are subscribing to ISDN services. Each customer is using a fractional PRI
service. Each customer could be directly connected to the ISDN switch, which would consume three fractional
T1/E1 circuits, and three D channels. Instead, the 3 fractional ISDN circuits are connected to a PRI Server equipped
IMACS. The PRI server grooms the B channels in the three fractional ISDN circuits into one circuit. It also grooms
the three D-channel circuits into a single D channel that is routed to the switch. The IMACS benefits in this
application include saving on back haul costs, switch port costs and switch system resources.
23B+D on T1
30B+D on E1
Customer 1
10B+D
ISDN
Switch
IMACS
Customer 2
7B+D
Customer 3
5B+D
Figure 23—Fractional PRI Provisioning Using IMACS
ISDN Video Conferencing and Video Broadcast
The IMACS is used to connect video-conferencing equipment to an ISDN PRI line. In Figure 24, a video CODEC
is sharing a PRI line with an ISDN PBX. The IMACS is simultaneously routing calls on a call by call basis to either
the PBX, the CODEC, or out to the network. The video-conferencing equipment can be connected via an RS-449
connection with an RS-366 dialer or directly to the IMACS via an ISDN PRI interface. A connection to the
IMACS via the RS-449/RS-366 combination would require the use of a switched HSU card in the IMACS.