Zhone Technologies Network Device manual Fractional PRI Provisioning, Customer 1 10B+D 7B+D

Zhone Technologies, Inc. IMACS Product Book, Version 4

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.

Customer 1 10B+D

Customer 2
7B+D	IMACS

ISDN

Switch

23B+D on T1

30B+D on E1

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.

March 2001 Page 72