Analysis techniques for loop qualification and spectrum management

The telecommunications industry has worked for over a decade to develop digital subscriber line (DSL) technologies to revitalize the embedded copper plant. Now the industry is on the threshold of reaping the benefits of this effort, bringing megabit-per-second connectivity to offices and homes. However, network providers must properly manage the introduction and application of these systems to the local network. Accurate engineering is critical to avoid incompatibilities and failed provisioning that would otherwise create customer disappointment, delay and higher costs. An understanding of subscriber loop make-ups, including length, wire gauge and location of bridged taps, is key to the proper engineering of DSL systems. While some loop records exist, they may be inaccurate or out of date. Knowing the types of systems that are transmitting in a given cable is also critical, because of the resultant crosstalk and the potential need for spectrum management. In this paper, we describe techniques for obtaining precise loop make-ups, and for determining the current crosstalk profile in the loop plant. 1. Achieving the Full Potential o