Economic Considerations of Fiber in the Loop Plant

Subject to the current business, market and regulatory climate in the U.S., some telephone companies are basing initial residential fiber projects on basic telephone service[1]. The objective of this paper is to determine when fiber in the distribution network will be at economic parity with copper, what the sensitivities are, and how the prospect of fiber distribution will impact near-term planning of fiber versus copper in the feeder network. 

This study indicated economic crossover ranging from late 1989 to 1995 with the nominal occurring in 1992. Technology cost trend assumptions were found to have the largest impact on the crossover range. In feeder planning, it was found that digital loop carrier on fiber is the economic choice over copper for feeder lengths greater than approximately 8 kft, if the distribution area is to be converted to fiber in the early 1990s.