Specifications

2-38
Reference Guide
Model No.
Running Head
Frame Relay Access and Concentration Server Applications
2.8.3 IDSL Service Provisioning
This integrated access system with a Frame Relay server can be used for efficient ISDN DSL
(IDSL) provisioning for Internet access at speeds up to 128K. Each BRI card provides up to
eight IDSL ports over single twisted pair wire. There can be up to seven such BRI cards in an
800/900 chassis. This arrangement cost-effectively replaces external DDS CSU/DSU
equipment and offers higher bandwidth.
Each Frame Relay server supports up to 35 NTUs at 128K over 1 T1 (with 3:1 concentration)
or 1 E1 (with 2.5:1 concentration), thereby taking advantage of frame relay’s statistical
multiplexing capabilities.
Up to 64 DS0s are channelized through the Frame Relay Server ports and are concentrated
onto a single port connected to the network. Three concentrator ports bring in additional
NXDS0s channels to be concentrated onto the single outgoing port as shown in Figure 2-24.
Figure 2-24. IDSL Service Provisioning
• Support data rates up to 128 kbps over single twisted
pair over 5Km
• DDS CSU / DSU replacement with BRI-NTU scenarios
.
64/128Kbps
Frame Relay
64/128Kbps
Frame Relay
T1/E1
Ethernet
BRI Cards provide 2B1Q IDSL termination
FRS provides IDSL concentration
NTU
Frame Relay
Network
Ethernet
Router
2B1Q
Router
2B1Q
NTU
Router
2B1Q
NTU
Ethernet
64/128Kbps
Frame Relay