Zhone Technologies 800 ユーザーズマニュアル

5-1

The ISDN-PRI server card (884060) offers users the ability to effectively terminate and 
manage both dedicated and switched carrier services in a single system. This capability allows 
users to pick the most cost-effective services for both permanent connections (e.g., 
LAN-to-WAN) and periodic connections (e.g., video conferencing).

Three specific features enable the system to use ISDN-PRI services, and are therefore covered 
in this chapter. These features are:

ISDN PRI server card

Call profiles (accessed from the Interface Card)

HSU-AD 530/35 switched services data card

The switched services HSU card information is repeated in the chapter on HSU cards, and the 
call profile information is repeated in the Interface Card chapter.

Each T1 or E1 WAN link accessed by the system is subdivided into individual 64 kbps 
channels called timeslots (T1 has 24 timeslots, E1 has 32). A timeslot is sometimes also called 
a DS0 or a B (bearer) channel. While all three terms refer to the same concept, this manual 
will assign arbitrary definitions to distinguish timeslots controlled by ISDN from those that 
are not.

A DS0 is a timeslot on any WAN link that is not controlled by an ISDN signaling channel 
(the D channel). Thus, DS0s are controlled via assigning user ports to WAN timeslots (see 
individual user card chapters) via setting up cross-connect circuits (see Chapter 4, System 
Configuration and Operation, in the System Reference Guide).