PDF user manual for CopperEdge 150

In general, the netmodels behave quite differently and requirevery different configuration. Later in this appendix we will discusseach netmodel separately. But first we describe some commonprinciples used in the CE150.The CE150 is a DSLAM, or Digital Subscriber Line Access Multiplexor.Therefore, it is primarily a data forwarding and multiplexingdevice that connects DSL subscribers to NetworkService Providers (NSPs). An NSP may be a third-party serviceprovider, such as an Internet Service Provider (ISP), or it maybe a private company providing data services to its employeesor branch offices. The CE150 forwards the vast majority of userdata between subscribers and their NSPs. As part of the forwardingprocess, the CE150 often modifies the data in someway, but very little user data actually terminates in the CE150.Although the CE150 can forward data between any two interfaces,most applications involve the CE150 aggregating upstreamtraffic from many DSL subscribers into one (or a few)multiplexed WAN interfaces, and demultiplexing downstreamtraffic from the multiplexed WAN interface to many DSL subscribers.A multiplexed WAN interface is typically a high-speedFrame Relay or ATM interface, with many independent virtualcircuits (VCs) on it. Each virtual circuit is a logical point-topointlink to an NSP. Note that in some configurations, the WANinterface can be a CE150 Ethernet port, or even another DSLport.CopperEdge DSLAMCopperEdge DSLAMDSLWANDSLWANUpstreamDownstreamCE150 with Upstream and Downstream TrafficDSL subscribers are usually connected, at subscription time, toa single NSP, and therefore, to a single VC on the WAN interface.Thus, you can often think of CE150 configuration as connectingCE150 DSL ports to CE150 WAN VCs.&RSSHU(GJH,QVWDOODWLRQDQG2SHUDWLQJ*XLGH