CCIE Practical Studies: Security (CCIE Self-Study)

ISDN Overview

ISDN was developed to provide integrated access to the widest range of services such as voice, video, and, of course, data. Its ability to effectively connect small offices, home offices, and telecommuters to the central site allows companies specializing in different industrial and service fields to use several new voice and data services that were not available over the traditional network while maintaining their investment in existing technology. Such services could not have been economically accessed in the old basic telephone service/Public Switched Telephone Network (PSTN) environment.

ISDN Standards Support

To communicate from the local terminal equipment to the ISDN switch in the central office, ISDN uses a unique collection ...