Chapter 1. Introduction
1-2 ATLAS 550 User Manual 61200305L1-1
Access Router
As an Access Router, the ATLAS 550 combines the functions of a T1 CSU/
DSU, an intelligent channel bank, a T1 Multiplexer, and DACS into a single
platform. The ATLAS 550 is ideal for point-to-point configurations or access
to public networks. For optimization of existing equipment and network re-
sources, the ATLAS 550 can support a variety of data and analog voice ap-
plications (see Figure 1-1 ). The Access Router also supports a wide range of
data applications including T1 “drop and insert,” channel grooming, and
wide area data transport.
Figure 1-1. Point-to-Point Circuit with External Routers
Frame Relay/Router
The Frame Relay/Router features enable the Access Router to act as a voice/
data FRAD, a frame relay switch, and an IP router in addition toacting as an
available bandwidth manager and a switch application.
Frame Relay
Frame relay is a packet-switched service that allows efficient transfer of
bursty traffic in a WAN environment. It offers lower-cost data transfer
when compared to typical point-to-point applications. Using virtual con-
nections within the frame relay network and combining those into a single
physical connection at each location result in lower cost. Frame relay pro-
vidersuseaframerelayswitchtoroutethedataoneachvirtualcircuitto
the appropriate destination. Figures 1-1 and 1-2 illustrate a conversion from
a typical point-to-point application to a frame relay application.
Router
Router
Router
Router
PBX
PBX
PBX
Frac T1
Frac T1
Frac T1
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ATLAS 550 using
an external router.
TSU 100e
TSU 100e
TSU 100e
