Chapter 1. Introduction1-2 ATLAS 550 User Manual 61200305L1-1Access RouterAs 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 singleplatform. The ATLAS 550 is ideal for point-to-point configurations or accessto 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 ofdata applications including T1 “drop and insert,” channel grooming, andwide area data transport.Figure 1-1. Point-to-Point Circuit with External RoutersFrame Relay/RouterThe 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 to acting as anavailable bandwidth manager and a switch application.Frame RelayFrame relay is a packet-switched service that allows efficient transfer ofbursty traffic in a WAN environment. It offers lower-cost data transferwhen compared to typical point-to-point applications. Using virtual con-nections within the frame relay network and combining those into a singlephysical connection at each location result in lower cost. Frame relay pro-viders use a frame relay switch to route the data on each virtual circuit tothe appropriate destination. Figures 1-1 and 1-2 illustrate a conversion froma typical point-to-point application to a frame relay application.RouterRouterRouterRouterPBXPBXPBXFrac T1Frac T1Frac T1POWERREMOTEERRORTESTOKTESTONLINESTATUSERRORTESTOKCRAFTACOALARM ALARM1 2NETWORK1 2 3 4MODULESSYSTEMETHERNETATLAS 550ATLAS 550 usingan external router.TSU 100eTSU 100eTSU 100e
