Specifications

2-40

Reference Guide

Model No.

Running Head

Frame Relay Access and Concentration Server Applications

2.8.5 Frame Relay Concentration at Hub Sites

In the application shown in Figure 2-26, a corporation which serves a wide geographical area

through multiple branch offices is able to utilize the Frame Relay server’s ability to

consolidate and multiplex multiple NX56/64K circuits into a single high-speed facility. This

significantly reduces its access charges from its service provider for its corporate Frame Relay

network. Typical examples include banks, health care providers, technology parks, etc.

The branch offices typically subscribe to a Frame Relay service with a Committed

Information Rate (CIR) of 56/64K. At the Head Office/Data Center the traffic is typically from

a “farm” of front end processors, routers and servers. Without an IAD+FRS at the Head

Office/Data Center, multiple circuits would occupy multiple ports in the service provider’s

switch and would be tariffed for lower individual speeds. With an IAD+FRS, the multiple

lower speed circuits are consolidated and groomed into a single/few high-speed (Nx64K)

circuit. Since the marginal access charge of Frame Relay is lower at higher speeds, due to

economies of scale, this could reduce costs.

Figure 2-26. Frame Relay Concentration at Corporate Headquarters

56/64K

FRAD

Data Proc

Application

FEP

HEAD OFFICE/DATA ENTER

IAD

Router

T1 Frame

Relay

Frame Relay

Network

FRAD

FEP

56/64K

BRANCH OFFICES