Introduction

Most of us take the high quality and reliability of telecommunications infrastructure for granted. When we pick up the phone, we just expect it to work. Following the California earthquakes in 1989 and 1994, telephone service remained operational even when other basic utilities were interrupted. The performance standards for modem networks keep increasing. ¹ Meanwhile, the deployment of digital technology, high capacity fiber optics, and software control promise a wealth of new services ranging from relatively mundane enhanced calling options such as voice mail, call forwarding, and automatic number identification to more advanced services such as virtual private networks, integrated multimedia, and value-added information services. Few of the products or services we experience in our daily lives have offered such a history of steadily improving quality and reliability. However, few services are as critical to the smooth operation of modem economies as a communications infrastructure.