Zhone Technologies 600, 900, 800 manual Selecting D Channels, B Channels, and DS0s, Trunks

ISDN-PRI Card Introduction

5.1.1.8Trunks

An ISDN trunk is a logical division of B channels pertaining to a D channel. It consists of one or more contiguous or non-contiguous B channels. All B channels in a trunk must belong to the same D channel. However, a trunk may be assigned across different physical interfaces when NFAS is used.

5.1.2Selecting D Channels, B Channels, and DS0s

The D channel configuration screens described later in this chapter show how to configure D channels, assign B channels to one or more D channels, and how to identify dedicated DS0s that cannot be used as B channels. This section will give a few examples of applications that would require various combinations of D channel(s), B channels, and DS0s.

Figure 5-1shows an application where a single D channel performs ISDN signaling for 8 T1’s worth of B channels (191 B+D). There are actually 8 separate T1 facilities: seven with 24 B channels each, and one with 23 B channels and one D channel.

Carrier

ISDN Switch

7 Facilities With	1 Facility With 23B+D
24B Each

IAD

Figure 5-1. ISDN Channels: 191B+D

Server Cards 5-3