The concept of the wired city is based upon the facility and capacity of the CATV network. The original concept envisioned "everything for everybody"~but progress has been retarded by the lack of economically viable services. Over the years individual stand alone services have been developed as income producers with some degree of success. Addressable control of premium television has been the most successful and Profitable and is now being augmented by home security, utility meter reading and pay-per-event TV. The future promises the addition of more sophisticated services including videotex,~ interactive home shopping and personal computer interfacing plus banking. These business ventures are being fine tuned to be good revenue producers so that indeed the wired city concept is coming into much sharper focus.
With the economic driving forces building, and in some cases firmly in place, it is well to review the technical approach for delivery of these services on the CATV network. Typically, services of this sort are implemented on a stand-alone basis. Manufacturers and program suppliers, experts in their areas, have devised and configured transmission systems including headend subscriber equipment to provide efficient and economical delivery of each individual service. This has resulted in optimization of stand-alone services which in turn has resulted in deficiencies and complexities when multiple interactive services are implemented on a single cable system. The following discussion cites the need for and proposes a multiple service system for CATV carriage of subscriber services.