Broadband video switch that performs program merging and method therefor

Abstract

A network (,) includes a broadband customer service module (B-CSM) (,). The B-CSM (,) includes a plurality of feeder interface cards (FICs) (,) and optical line cards (OLCs) (,) which are coupled together through a midplane assembly (,) so that each FIC (,) couples to all OLCs (,) and each OLC (,) couples to all FICs (,) through junctor groups (,). Within the B-CSM (,) circuit switching is performed electrically at an STS-1 rate. A reference clock which oscillates at a frequency slower than the data rate is routed with payload data so that it receives delays similar to those imposed on the payload data due to processing. At second stage switching fabrics (,) where data need to be extracted from signals flowing within the B-CSM (,), a clock regeneration circuit (,) generates a master clock signal oscillating at twice the data rate and phase synchronized to a delayed reference clock. A geometric compensation scheme corrects for timing skew which occurs when clocks and data are distributed to points or small areas from widely dispersed locations, and when clocks and data are distributed from points or small areas to widely dispersed locations. A variation of the Q.931 signaling protocol is implemented to enable the B-CSM (,) to respond to a request from a second subscriber interface unit (SIU) (,) to view a video program currently being delivered to a first SIU (,). The second SIU (,) need not have access to the identity of the video program before sending the switching request.