This section is based on the book 'Qualifying Copper' by Alan Keene. This section can be used as a reference for anyone who is responsible for the provision of Digital Subscriber Loop services. It is intended for engineers whose background may be in data communications but who now have to understand in some detail how local copper access loops behave and how they can affect the digital services that they are carrying. 

Those transmission engineers who already have a good understanding of copper pair technology may also find some sections of interest.

The module covers aspects of the theory which are relevant to addressing the problems facing DSL provisioning engineers, including an appendix dealing with decibels by way of a refresher for those who need it. It also suggests various approaches to the problem of qualifying the copper, to help the reader to formulate a strategy which suits his particular business.

In the title and text, the term "copper" is used generically and by implication includes cables made from aluminium and other materials.