Architecture For Delivery Of Broadband Services To The Residence

Abstract

This paper presents a technology and architecture perspective on the cost of evolving today's copper access network, optimized for POTS, to a fibre access network providing both narrowband and broadband services. Architectures are assessed using application studies based on cost models for actual routes in North America. This study identifies three architectures as serious candidates (i.e. close to copper in cost) for providing POTS service in 1992: the double star, the active pedestal and the star-bus.The active pedestal and the star-bus architectures were similar in first costs and were the least expensive, costing between 5 and 15 per cent more than the copper reference depending on the number of subscribers subtending a given optical fibre. The double star is 20 per cent more expensive than the copper reference. All three architectures are potentially attractive for broadband service upgrade depending on the bandwidth required per subscriber. The star-bus is most bandwidth sensitive. Moderate video bandwidths, nominally 150 Mblslsubscriber, favour the active pedestal architecture. Conversely, service environments requiring much greater than 150 Mblslsubscriber favour the double star architecture. KEY WORDS Fibre architectures Installed first costs Star and double star Star-bus Active pedestal Narrowband Broadband upgrade