Fiber backbone trunking in cable television networks: an evolutionary adoption of new technology

The competitive forces that are motivating the cable industry to change are examined. The prominent sources of competition discussed are direct broadcast satellite, multichannel multiport distribution service, and the telephone companies. The characteristics of the two transmission media offering realistic choices for the delivery of video over a terrestrial network, namely, coaxial cable and optical fiber, are described. Fiber-optic supertrunks used in the cable television industry for point-to-point delivery of video signals and the tree-and-branch architecture used in current cable systems are also described. An evolutionary concept for the integration of fiber into cable systems, called fiber backbone, is presented. It consists of overlaying most of the existing trunk system with optical fiber cables. A direct passive optical fiber path is established from the headend to a number of feed points in the cable television distribution network. At these points, broadband multichannel information is converted from the optical back to the RF broadband domain, and, from that point on, the existing coaxial plant is utilized. The design and implementation of such a hybrid system are discussed.<>