Cisco 2600 Series Operation Manual page 81

Connecting ISDN PRI Network
Modules to a Network
This chapter describes how to connect Integrated Services Digital Network (ISDN)
Primary Rate Interface (PRI) network modules used in Cisco modular routers, and
describes the following modules:
•
1-Port and 2-Port Channelized T1/ISDN PRI Network Modules on page 8-2
•
1-Port and 2-Port Channelized T1/ISDN PRI with CSU Network Modules on page 8-5
•
1-Port and 2-Port Channelized E1/ISDN PRI Balanced (120-ohm) Network Modules on
page 8-9
•
1-Port and 2-Port Channelized E1/ISDN PRI Unbalanced (75-ohm) Network Modules
on page 8-14
Unless specifically identified, references to PRI modules in this chapter include all these
network modules.
Do not install an ISDN Basic Rate Interface (BRI) network module in the same
Note
chassis as an ISDN PRI network module, unless you are using Cisco IOS Release 11.3(3)T
or later. Earlier Cisco IOS releases do not support this configuration.
CT1/PRI modules are available with or without a built-in channel service unit (CSU) and
with one or two ports. The CT1/PRI modules connect to an external CSU, whereas the
CT1/PRI-CSU modules connect directly to the network. Each T1 module provides up to 24
virtual channels per T1 port, and each virtual channel is presented to the system as a serial
interface that can be configured individually. The T1 interface is the physical medium that
supports ISDN PRI.
Connecting ISDN PRI Network Modules to a Network 8-1
C H A P T E R 8