By Thomas E. O'Brien Jr., Jerrold Division General Instrument Corporation
Pay TV has now emerged as a primary driving force for the rapid expansion of CATV subscriber growth. Effective control of subscriber access to premium programs can be realized through the availability of low cost subscriber terminals, capable of remote authorization of multi-tier subscription and eventually pay per view services. Providing reliable terminal equipment with increased capability at low cost, represents both a challenge and an opportunity for CATV manufacturers. The limitations of the traditional approach to data distribution are examined and compared to the emerging trends in newer system designs. The trade-offs and specific solutions to the problems of authorization speed and data format are presented. A headend distributed computer architecture is also discussed which results in lower initial oo•t and overhead while permitting the multiple system operator to exploit the advantages of simplified on-site upgradability and reduced spare part inventory. Techniques which permit simplified, cost effective solutions to the problems associated with cable system growth, are also discussdr