Table of Contents:

Definition and Overview

1. History of Subscriber Carriers

2. Early Next-Generation Digital Loop Carriers

3. Next-Generation Digital Loop Carriers for Rural and Suburban Applications

4. NGDLC Applications

5. Future Directions

6. Economics

7. The Multiservice DLC

Self-Test

Glossary

PDF of this tutorial

Definition
The local loop is the physical connection between the main distribution frame in the user's premises to the telecommunications network provider. Digital loop carrier (DLC) technology makes use of digital techniques to bring a wide range of services to users via twisted-pair copper phone lines

Overview
The telecommunications infrastructure has undergone a great deal of change recently, and it seems that the rate of change increases exponentially as time passes. For example, DLC technology and the local loop will become more important in the future in delivering the new services that customers will require. This tutorial first addresses the history of subscriber carriers because it is important in providing clues to the future. It will then discuss some of the early next-generation digital loop carriers (NGDLC) that began to appear in the 1980s, as well as the NGDLC as a cost-effective solution for suburban and rural applications. Finally, it will explore the likely direction that loop technology will take in the future and how to enable the market for some of the more advanced services that are expected.