The broadband customer service module (B-CSM): an access and switching module serving SONET OC-12 fiber lines

The module is intended for residential applications in a broadband network and can independently provide a variety of video services, including broadcast-like entertainment video service. It is based on a midplane arrangement; two types of cards that each contain SONET OC-12 interfaces and STM fabrics operating at the STS-1 rate; and multiple processors that provide both call processing and packet switching features. The target architecture can serve 288 SONET OC-12 fiber lines, each with signalling based on Q.921 and Q.931. A prototype module has been built to demonstrate feasibility; it is now operating in a technology and service trial where it can serve up to 18 SONET OC-12 fiber lines