Deconstructing the Divide: Extending Broadband xDSL Services to the Periphery

One of the major challenges to providing full-rate digital subscriber line (xDSL) access to residential customers in rural or remote locations is the use of existing copper infrastructure. First, copper is not particularly good for moving high frequencies over extended distances. Second, much of the existing copper in the United States is of diminished quality. Third, digital loop carriers, bridge taps, load coils, and ambient interference negatively impact data transmission. Because of these problems, the geographic reach of xDSL services is limited. To combat this limitation, providers are installing remote digital subscriber line access multiplexers (RDSLAMs). RDSLAMs seek to maximise the amount of demand covered for a peripheral neighborhood and aggregate this data traffic onto a fiber optic connection for transport back to the central office (CO) for switching. Although this is more feasible than constructing a new CO, acquiring the rights of way and installing fiber is expensive. The purpose of this paper is to examine the complexities associated with locating RDSLAMs in a competitive telecommunications market through the use of an integer programming model—the remote access hierarchical assignment problem—and a geographic information system. Pertinent policy and technology related issues in residential broadband deployment and their impacts on high-speed services such as xDSL are highlighted.