Chapter 9: Planning for and Installing ISDN

Wiring For ISDN

In more than 80 percent of existing locations, the copper twisted-pair lines that currently serve analog telephones can be successfully used for ISDN. Nonetheless, depending on the usage of the ISDN line, and the number of existing handsets or other devices currently installed, those who plan to order ISDN may want to consider the costs and advantages of several alternatives.

ISDN as the only line.
This requires that all equipment (telephones, terminal adapters and the like) be ISDN-compatible. Several variations of equipment can be used to configure the line, depending on needs and projected customer applications.

ISDN as a second line.
This alternative can also be configured in several ways, and lets existing analog lines serve analog phones and faxes. A drawback: it may not be possible to "roll over" calls between equipment on the various lines. An advantage: analog lines can function through a power outage, while ISDN lines can not without adequate battery or other power backup.

Other Sections Of This Chapter:

Beginning Of Chapter 9
The Movement Towards Unity
NYNEX ISDN Services
ISDN Basic Service
ISDN Intellipath
ISDN Primary Service
ISDN Equipment
Wiring For ISDN
Getting Started Now