A telecommunications system for providing both narrowband and broadband services to subscribers

摘要

An architecture, as well as various components, of an asynchronous transfer mode (ATM) subscriber access multiplexer (ASAM) system can be implemented using an xDSL (x-Digital Subscriber Line) using DMT (Discrete Multitone) or CAP (Carrierless Amplitude Phase Modulation) between a plurality of subscribers and a corresponding plurality of line termination equipment in a shelf that also includes network termination equipment for connection to an ATM network. The line termination and network termination equipment are interconnected by a bus internal to the shelf for providing subscriber access. Separate lowpass filters are provided at each end of a twisted wire pair between the shelf and each subscriber equipment. A shelf can be used as a hub for connecting to a remote shelf that includes the line termination equipment for connection to subscribers. Although the internal bus of the shelf is shown in a non-redundant embodiment, an increased level of equipment protection can be provided by placing one half of a redundant equipment pair in one.shelf and the other half in the other shelf and sharing network termination equipment between such shelves.