Cisco NM-1CT1 Quick start guide

1
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1-Port and 2-Port ISDN-PRI Network Module
Configuration Note
Product Numbers:
NM-1CT1, NM-1CT1-CSU, NM-2CT1, NM-2CT1-CSU, NM-1CE1-B, NM-2CE1-B,
NM-1CE1-U, NM-2CE1-U
CPANM-1CT1, CPANM-1CT1-CSU, CPANM-2CT1, CPANM-2CT1-CSU,
CPANM-1CE1-B, CPANM-2CE1-B, CPANM-1CE1-U, CPANM-2CE1-U
This document provides information about the following network modules for the Cisco 3600 series
of modular access routers:
•1-port channelized T1/ISDN-PRI network module, Cisco product number NM-1CT1 or
CPANM-1CT1. (See Figure 1.) This module will also be referred to as the 1-port CT1/PRI
network module.
•2-port channelized T1/ISDN-PRI network module, Cisco product number NM-2CT1 or
CPANM-2CT1. (See Figure 2.) This module will also be referred to as the 2-port CT1/PRI
network module.
•1-port channelized T1/ISDN-PRI with CSU network module, Cisco product number
NM-1CT1-CSU or CPANM-1CT1-CSU. (See Figure 3.) This module will also be referred to as
the 1-port CT1/PRI-CSU network module.
•2-port channelized T1/ISDN-PRI with CSU network module, Cisco product number
NM-2CT1-CSU or CPANM-2CT1-CSU. (See Figure 4.) This module will also be referred to as
the 2-port CT1/PRI-CSU network module.
•1-port channelized E1/ISDN-PRI balanced (120-ohm) network module, Cisco product number
NM-1CE1BorCPANM-1CE1B. (See Figure 5.) This module will also be referred to as the 1-port
CE1/PRI-B network module.
78-3052-01

21-Port and 2-Port ISDN-PRI Network Module Configuration Note
•2-port channelized E1/ISDN-PRI balanced (120-ohm) network module, Cisco product number
NM-2CE1B or CPANM-2CE1B. (See Figure 6.) This module will also be referred to as the
2-port CE1/PRI-B network module.
•1-port channelized E1/ISDN-PRI unbalanced (75-ohm) network module, Cisco product number
NM-1CE1U or CPANM-1CE1U. (See Figure 5.) This module will also be referred to as the
1-port CE1/PRI-U network module.
•2-port channelized E1/ISDN-PRI unbalanced (75-ohm) network module, Cisco product number
NM-2CE1U or CPANM-2CE1U. (See Figure 6.) This module will also be referred to as the
2-port CE1/PRI-U network module.
Unless specifically identified, references to PRI modules in this configuration note include all these
network modules.
Figure 1 1-Port Channelized T1/ISDN-PRI Network Module
Figure 2 2-Port Channelized T1/ISDN-PRI Network Module
Figure 3 1-Port Channelized T1/ISDN-PRI with CSU Network Module
LOOPBACK
CTRLR 0 EN
cT1
PRI
H7462
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CT1/PRI LEDs Enable LED
LOOPBACK
CTRLR 0 EN
cT1
PRI
H7463
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
LOOPBACK
CTRLR 1
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CT1/PRI LEDs Enable LED
CT1/PRI LEDs
LOOPBACK
EN
cT1
CSU
H7467
LOCAL ALARM
REMOTE ALARM
CARRIER DETECT
RX
OUT RX MON
CTRLR 0
TX
IN
CT1/PRI-CSU LEDs

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 3
Figure 4 2-Port Channelized T1/ISDN-PRI with CSU Network Module
Figure 5 1-Port Channelized E1/ISDN-PRI Network Module (Balanced or Unbalanced)
Figure 6 2-Port Channelized E1/ISDN-PRI Network Module (Balanced or Unbalanced)
Use this document in conjunction with your router installation and configuration guide and the
Regulatory Compliance and Safety Information publication.Ifyouhavequestionsorneedhelp,refer
to the section “Obtaining Service and Support” later in this document for further information.
This document contains the following sections:
•Safety Recommendations, page 4
•Required Tools and Equipment, page 6
•Installing PRI Network Modules in a Chassis Slot, page 7
•Connecting the PRI Module to the Network, page 8
•PRI Module Pinouts, page 11
LOOPBACK
EN
cT1
CSU
H7466
LOCAL ALARM
REMOTE ALARM
CARRIER DETECT
RX
OUT RX MON
CTRLR 1
CTRLR 0
TX
IN
LOOPBACK LOCAL ALARM
REMOTE ALARM
CARRIER DETECT
CT1/PRI-CSU LEDs
CT1/PRI-CSU LEDs
LOOPBACK
CTRLR 0 EN
cE1
PRI
H7262
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CE1/PRI LEDs Enable LED
LOOPBACK
CTRLR 0 EN
cE1
PRI
H7263
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
LOOPBACK
CTRLR 1
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CE1/PRI LEDs Enable LED
CE1/PRI LEDs

41-Port and 2-Port ISDN-PRI Network Module Configuration Note
Safety Recommendations
•PRI Module LEDs, page 14
•Configuring the PRI Interfaces, page 17
•Obtaining Service and Support, page 22
•Cisco Connection Online, page 22
Warning Only trained and qualified personnel should be allowed to install or replace this
equipment. (To see translated versions of this warning, refer to the Regulatory Compliance and
Safety Information document that accompanied the router.)
Warning Before working on a chassis or working near power supplies, unplug the power cord on
AC units; disconnect the power at the circuit breaker on DC units. (To see translated versions of this
warning,refertotheRegulatoryComplianceandSafetyInformationdocumentthataccompaniedthe
router.)
Warning Ultimate disposal of this product should be handled according to all national laws and
regulations. (To see translated versions of this warning, refer to the Regulatory Compliance and
Safety Information document that accompanied the router.)
Caution To avoid damaging electrostatic discharge (ESD)-sensitive components, ensure that you
have discharged all static electricity from your body before opening the chassis. Before performing
procedures described in this document, review the next section, “Safety Recommendations.”
Safety Recommendations
Follow these guidelines to ensure general safety:
•Keep the chassis area clear and dust-free during and after installation.
•Put the removed chassis cover in a safe place.
•Keep tools away from walk areas where you or others could fall over them.
•Do not wear loose clothing that could get caught in the chassis. Fasten your tie or scarf and roll
up your sleeves.
•Wear safety glasses when working under any conditions that might be hazardous to your eyes.
•Do not perform any action that creates a potential hazard to people or makes the equipment
unsafe.
Warning The ISDN connection is regarded as a source of voltage that should be inaccessible to
user contact. Do not attempt to tamper with or open any public telephone operator (PTO)-provided
equipment or connection hardware. Any hardwired connection (other than by a nonremovable,
connect-one-time-only plug) must be made only by PTO staff or suitably trained engineers. (To see
translated versions of this warning, refer to the Regulatory Compliance and Safety Information
document that accompanied the router.)

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 5
Safety Recommendations
Warning Network hazardous voltages are present in the BRI cable. If you detach the BRI cable,
detach the end away from the router first to avoid possible electric shock. Network hazardous
voltages also are present on the system card in the area of the BRI port (RJ-45 connector), regardless
of when power is turned off. (To see translated versions of this warning, refer to the Regulatory
Compliance and Safety Information document that accompanied the router.)
Warning The Ethernet 10BaseT, Token Ring, serial, console, and auxiliary ports contain safety
extra-low voltage (SELV) circuits. BRI circuits are treated like telephone-network voltage (TNV)
circuits. Avoid connecting SELV circuits to TNV circuits. (To see translated versions of this
warning,refertotheRegulatoryComplianceandSafetyInformationdocumentthataccompaniedthe
router.)
Safety with Electricity
Warning Before workingonequipmentthatisconnected to powerlines,removejewelry(including
rings, necklaces, and watches). Metal objects will heat up when connected to power and ground and
can cause serious burns or weld the metal object to the terminals. (To see translated versions of this
warning,refertotheRegulatoryComplianceandSafetyInformationdocumentthataccompaniedthe
router.)
Follow these guidelines when working on equipment powered by electricity:
•Locate the emergency power-OFF switch in the room in which you are working. Then, if an
electrical accident occurs, you can quickly shut the power OFF.
•Before working on the router, turn OFF the power and unplug the power cord.
•Disconnect all power before doing the following:
—Installing or removing a router chassis
—Working near power supplies
—Performing a software upgrade
•Do not work alone if potentially hazardous conditions exist.
Warning Before opening the chassis, disconnect the telephone-network cables to avoid contact
with telephone-network voltages. (To see translated versions of this warning, refer to the Regulatory
Compliance and Safety Information document that accompanied the router.)
Warning Do not work on the system or connect or disconnect cables during periods of lightning
activity. (To see translated versions of this warning, refer to the Regulatory Compliance and Safety
Information document that accompanied the router.)
•Never assume that power is disconnected from a circuit. Always check.

61-Port and 2-Port ISDN-PRI Network Module Configuration Note
Required Tools and Equipment
Warning Do not touch the power supply when the power cord is connected. For systems with a
power switch, line voltages are present within the power supply even when the power switch is OFF
and the power cord is connected. For systems without a power switch, line voltages are present
within the power supply when the power cord is connected. (To see translated versions of this
warning,refertotheRegulatoryComplianceandSafetyInformationdocumentthataccompaniedthe
router.)
•Look carefully for possible hazards in your work area, such as moist floors, ungrounded power
extension cables, and missing safety grounds.
•If an electrical accident occurs, proceed as follows:
—Use caution; do not become a victim yourself.
—Turn OFF power to the router.
—If possible, send another person to get medical aid. Otherwise, determine the condition of the
victim and then call for help.
—Determine if the person needs rescue breathing or external cardiac compressions; then take
appropriate action.
Preventing Electrostatic Discharge Damage
Electrostatic discharge (ESD) can damage equipment and impair electrical circuitry. It occurs when
electronic printed circuit cards are improperly handled and can result in complete or intermittent
failures. Always follow ESD prevention procedures when removing and replacing cards. Ensure that
the router chassis is electrically connected to earth ground. Wear an ESD-preventive wrist strap,
ensuring that it makes good skin contact. Connect the clip to an unpainted surface of the chassis
frame to safely channel unwanted ESD voltages to ground. To properly guard against ESD damage
and shocks, the wrist strap and cord must operate effectively. If no wrist strap is available, ground
yourself by touching the metal part of the chassis.
Caution For safety, periodically check the resistance value of the antistatic strap, which should be
between 1 and 10 megohms (Mohm).
Required Tools and Equipment
You need the following tools and equipment to install a network module in a Cisco 3600 series
chassis slot:
•Network module
•Number 1 Phillips screwdriver or small flat-blade screwdriver
•ESD-preventive wrist strap

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 7
Installing PRI Network Modules in a Chassis Slot
Installing PRI Network Modules in a Chassis Slot
Caution Network modules do not support online insertion and removal (hot swap). To avoid
damaging the module, before you insert a network module into a chassis slot, you must turn OFF
electrical power and disconnect network cables.
The following instructions apply only to installing network modules in a chassis slot. To install a
WAN interface card in a network module, see the configuration note for the WAN interface card.
You can install network modules in the chassis either before or after mounting the router, whichever
is more convenient.
Note Do not install a PRI network module in the same chassis as an ISDN Basic Rate Interface
(BRI) network module or a BRI WAN interface card. This configuration is not supported.
Follow this procedure to install a network module:
Step 1 Turn OFF electrical power to the router. However, to channel ESD voltages to ground, do
not unplug the power cable. Remove all network interface cables, including telephone
cables, from the rear panel.
The following warning applies to routers that use a DC power supply:
Warning Before performing any of the following procedures, ensure that power is removed from
the DC circuit. To ensure that all power is OFF, locate the circuit breaker on the panel board that
services the DC circuit, switch the circuit breaker to the OFF position, and tape the switch handle of
the circuit breaker in the OFF position. (To see translated versions of this warning, refer to the
Regulatory Compliance and Safety Information document that accompanied the router.)
Step 2 Using either a number 1 Phillips screwdriver or a small flat-blade screwdriver, remove the
blank filler panel from the chassis slot where you plan to install the module. Save the
blank panel for future use.
Step 3 Align the network module with the guides in the chassis and slide it gently into the slot.
Step 4 Push the module into place until you feel its edge connector mate securely with the
connector on the motherboard.
Step 5 Fasten the module’s captive mounting screws into the holes in the chassis, using the
Phillips or flat-blade screwdriver.
Step 6 If the router was previously running, reinstall the network interface cables and turn ON
power to the router.

81-Port and 2-Port ISDN-PRI Network Module Configuration Note
Connecting the PRI Module to the Network
The following warning applies to routers that use a DC power supply:
Warning After wiring the DC power supply, remove the tape from the circuit breaker switch handle
and reinstate power by moving the handle of the circuit breaker to the ON position. (To see translated
versions of this warning, refer to the Regulatory Compliance and Safety Information document that
accompanied the router.)
Blank Network Module Panels
If the router is configured with fewer than four network modules, make sure that blank panels fill the
open chassis slots to provide proper airflow. (See Figure 7.)
Figure 7 Blank Network Module Panel
Connecting the PRI Module to the Network
This section explains how to connect a PRI network module to a WAN.
CT1/PRI Modules
To connect a CT1/PRI module, use a DB-15-to-DB-15 T1 serial cable to connect the CT1/PRI port
to a T1 CSU. (See Figure 8.)
Figure 8 Connecting a CT1/PRI Module to a T1 CSU
H6552
LOOPBACK
CTRLR 0
EN
cT1
PRI
H7468
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
CT1/PRI port (DB-15)
CT1/PRI port (DB-15)
T1 serial
cable
T1 CSU

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 9
Connecting the PRI Module to the Network
CT1/PRI-CSU Modules
To connect a CT1/PRI-CSU module, use a straight-through RJ-48C-to-RJ-48C cable to connect the
RJ-48C port to an RJ-48C jack. (See Figure 9.)
Figure 9 Connecting a CT1/PRI-CSU Module to an RJ-48C Jack
CE1/PRI-B Modules
To connect a CE1/PRI-B (120-ohm) module, use the appropriate cable to connect the CE1/PRI-B
port to an E1 CSU. (See Figure 10, Figure 11, and Figure 12, showing DB-15, Twinax, and RJ-45
CSUs respectively.)
Figure 10 Connecting a 120-Ohm CE1/PRI-B Module to an E1 CSU (DB-15-to-DB-15 Connectors)
H7469
RJ-48C jack
CT1/PRI-CSU
port (RJ-48C)
LOOPBACK
EN
cT1
CSU
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
RX
OUT RX
MON
CTRLR 0
TX
IN
LOOPBACK
CTRLR 0
EN
cE1-B
PRI
H7470
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
CE1/PRI-B (DB-15)
DB-15 connector
E1 CSU
E1 cable for 120-ohm
balanced connections
with a DB-15 connector
at the network end

10 1-Port and 2-Port ISDN-PRI Network Module Configuration Note
Connecting the PRI Module to the Network
Figure 11 Connecting a 120-Ohm CE1/PRI-B Module to an E1 CSU (DB-15-to-Twinax Connectors)
Figure 12 Connecting a 120-Ohm CE1/PRI-B Module to an E1 CSU (DB-15-to-RJ-45 Connectors)
CE1/PRI-U Modules
To connect aCE1/PRI-U(75-ohm) module, use the appropriate cable to connecttheCE1/PRI-U port
to an E1 CSU. (See Figure 13.) The illustration shows a CSU with BNC connectors.
LOOPBACK
CTRLR 0
EN
cE1-B
PRI
H7473
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
CE1/PRI port (DB-15)
Twinax connectors
E1 CSU
E1 cable for 75-ohm
balanced connections
with twinax connectors
at the network end
LOOPBACK
CTRLR 0
EN
cE1-B
PRI
H7472
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
CE1/PRI port (DB-15)
RJ-45 jack
E1 cable for 120-ohm
balanced connections
with an RJ-45 connector
at the network end

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 11
PRI Module Pinouts
Figure 13 Connecting a CE1/PRI-U Module to an E1 CSU (DB-15-to-BNC Connectors)
PRI Module Pinouts
This section describes PRI network module cables and lists their pinouts.
CT1/PRI PinoutsTwo standard T1 serial cables are available for the CT1/PRI network module, straight-through and
null-modem. A straight-through cable connects the router to an external channel service unit (CSU).
Null-modem cables are used for back-to-back operation and testing.
T1 interface cables have two male DB-15 connectors (one at each end) to connect the CT1/PRI
module with the external T1 CSU. Figure 14 shows the cable and connectors. Table 1 lists the pinout
for the straight-through T1 cable, and Table 2 lists the pinout for the null-modem T1 cable.
Figure 14 T1 Interface Cable
LOOPBACK
CTRLR 0
EN
cE1-U
PRI
H7471
LOCAL
ALARM
REMOTE
ALARM
CARRIER
DETECT
CE1/PRI-U
BNC connectors
E1 CSU
E1 cable for 75-ohm
unbalanced connections
with BNC connectors
at the network end
Pin 1
Pin 9
Pin 11
Pin 3 Pin 1
Pin 9
Pin 11
Pin 3
72-XXXX-01 MIP
T1 or null-modem 
connector (typical)
H2385

12 1-Port and 2-Port ISDN-PRI Network Module Configuration Note
PRI Module Pinouts
Table 1 Straight-Through T1 Cable Pinout
Table 2 Null-Modem T1 Cable Pinout
CT1/PRI-CSU Pinout
Table 3 lists the pinout for the CT1/PRI-CSU network module.
Table 3 CT1/PRI-CSU Network Module (RJ-48C Port) Pinout
CE1/PRI PinoutsCiscoSystemsoffersthreeserialcablesfor120-ohmbalancedCE1/PRI-Bnetworkmodulesandone
serial cable for 75-ohm unbalanced CE1/PRI-U network modules. All four E1 cables have a DB-15
connector at the router end. Cables for CE1/PRI-B modules have either DB-15, Twinax, or RJ-45
connectors at the network end. (See Figure 15, Figure 16, and Figure 17.) The cable for CE1/PRI-U
modules has a BNC connector at the network end. (See Figure 18.)
DB-15 Connector DB-15 Connector
Signal Pin Pin Signal
Transmit Tip 1 1 Transmit Tip
Transmit Ring 9 9 Transmit Ring
Receive Tip 3 3 Receive Tip
Receive Ring 11 11 Receive Ring
DB-15 Connector DB-15 Connector
Signal Pin Pin Signal
Transmit Tip 1 3 Receive Tip
Receive Tip 3 1 Transmit Tip
Transmit Ring 9 11 Receive Ring
Receive Ring 11 9 Transmit Ring
RJ-48C Pin Signal
1 Receive Ring
2 Receive Tip
4 Ring
5 Tip

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 13
PRI Module Pinouts
Figure 15 E1 Interface Cable for 120-Ohm Balanced Connections (DB-15 Connector)
Figure 16 E1 Interface Cable for 120-Ohm Balanced Connections (Twinax Connectors)
Figure 17 E1 Interface Cable for 120-Ohm Balanced Connections (RJ-45 Connector)
Figure 18 E1 Interface Cable for 75-Ohm Unbalanced Connections (BNC Connectors)
H2476
H2424
H2422
H2421

14 1-Port and 2-Port ISDN-PRI Network Module Configuration Note
PRI Module LEDs
Table 4 lists pinouts for the CE1/PRI cables.
PRI Module LEDs
All network modules have an enable LED. This LED indicates that the module has passed its
self-tests and is available to the router.
All PRI modules display four additional LEDs for each port. These LEDs are described in Table 5.
Table 5 ISDN-PRI Network Module LEDs
The following sections illustrate these LEDs.
1. Tx = transmit. Rx = receive.
Table 4 CE1/PRI Network Module Cable Pinouts
CE1/PRI End Network End
DB-15 BNC DB-15 Twinax RJ-45
Pin Signal1Signal Pin Signal Pin Signal Pin Signal
9 Tx Tip Tx Tip 1 Tx Tip Tx-1 Tx Tip 4 Tx Tip
2 Tx Ring Tx Shield 9 Tx Ring Tx-2 Tx Ring 5 Tx Ring
10 Tx Shield – 2 Tx Shield Shiel
dTx Shield 6 Tx Shield
8 Rx Tip Rx Tip 3 Rx Tip Rx-1 Rx Tip 1 Rx Tip
15 Rx Ring Rx Shield 11 Rx Ring Rx-2 Rx Ring 2 Rx Ring
7 Rx Shield – 4 Rx Shield Shiel
dRx Shield 3 Rx Shield
LED Meaning
REMOTE ALARM Local alarm at remote end of connection
LOCAL ALARM Loss of signal, loss of frame, or
unavailability because of excessive errors
LOOPBACK Controller local loopback
CARRIER DETECT Carrier received on telco link

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 15
PRI Module LEDs
CT1/PRI Module LEDs
Figure 19 and Figure 20 show CT1/PRI network module LEDs.
Figure 19 1-Port CT1/PRI Network Module LEDs
Figure 20 2-Port CT1/PRI Network Module LEDs
CT1/PRI-CSU Module LEDs
Figure 21 and Figure 22 show CT1/PRI-CSU module LEDs.
Figure 21 1-Port CT1/PRI-CSU Network Module LEDs
LOOPBACK
CTRLR 0 EN
cT1
PRI
H7462
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CT1/PRI LEDs Enable LED
LOOPBACK
CTRLR 0 EN
cT1
PRI
H7463
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
LOOPBACK
CTRLR 1
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CT1/PRI LEDs Enable LED
CT1/PRI LEDs
LOOPBACK
EN
cT1
CSU
H7467
LOCAL ALARM
REMOTE ALARM
CARRIER DETECT
RX
OUT RX MON
CTRLR 0
TX
IN
CT1/PRI-CSU LEDs

16 1-Port and 2-Port ISDN-PRI Network Module Configuration Note
PRI Module LEDs
Figure 22 2-Port CT1/PRI-CSU Network Module LEDs
CE1/PRI Module LEDs
Figure 23 and Figure 24 show CE1/PRI module LEDs. The same LEDs are used for balanced
(120-ohm) and unbalanced (75-ohm) E1 interfaces.
Figure 23 1-Port CE1/PRI Network Module LEDs
Figure 24 2-Port CE1/PRI Network Module LEDs
LOOPBACK
EN
cT1
CSU
H7466
LOCAL ALARM
REMOTE ALARM
CARRIER DETECT
RX
OUT RX MON
CTRLR 1
CTRLR 0
TX
IN
LOOPBACK LOCAL ALARM
REMOTE ALARM
CARRIER DETECT
CT1/PRI-CSU LEDs
CT1/PRI-CSU LEDs
LOOPBACK
CTRLR 0 EN
cE1
PRI
H7262
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CE1/PRI LEDs Enable LED
LOOPBACK
CTRLR 0 EN
cE1
PRI
H7263
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
LOOPBACK
CTRLR 1
LOCAL ALARM REMOTE ALARM
CARRIER DETECT
CE1/PRI LEDs Enable LED
CE1/PRI LEDs

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 17
Configuring the PRI Interfaces
Configuring the PRI Interfaces
Whenever you install a new interface, or if you want to change the configuration of an existing
interface, you must configure the interface. If you replace a module that was already configured, the
router recognizes it and brings up the interface in the existing configuration.
Before you configure an interface, have the following information available:
•T1 or E1 information—for example, clock source, line code, and framing type
•Channel-group information and time-slot mapping
•Protocols you plan to route on the new interface
•IP addresses, subnet masks, network numbers, zones, or other information related to the routing
protocol
Timesaver Obtain this information from your system administrator or network plan before you
begin router configuration.
To configure a PRI interface, you must use configuration mode (manual configuration). In this mode,
you enter Cisco Internetwork Operating System (Cisco IOS) commands at the router prompt.
The following sections explain how to configure PRI interfaces. Before you begin, disconnect all
WAN cables from the router to keep it from trying to run the AutoInstall process. The router tries to
run AutoInstall whenever you power it ON if there is a WAN connection on both ends and the router
does not have a valid configuration file stored in nonvolatile random-access memory (NVRAM) (for
instance, when you add a new interface). It can take several minutes for the router to determine that
AutoInstall is not connected to a remote Transmission Control Protocol/Internet Protocol (TCP/IP)
host.
If you have questions or need help, refer to the section “Obtaining Service and Support” later in this
document for further information.
Configuring T1 Interfaces
The following procedure can be used to configure a new CT1/PRI or CT1/PRI-CSU module or to
change the configuration of an existing module.
To enter configuration mode, follow this procedure:
Step 1 Connect a console to the router. If you need instructions for connecting a console, refer
to the installation chapter of your router installation and configuration guide. Power up
the router.
Step 2 If the current configuration is no longer valid, after about a minute you see the following
prompt:
Would you like to enter the initial dialog? [yes]:
Answer no. You now enter the normal operating mode of the router.
Note If the current configuration is valid, you enter the normal operating mode
automatically.

18 1-Port and 2-Port ISDN-PRI Network Module Configuration Note
Configuring the PRI Interfaces
Step 3 After a few seconds you see the user EXEC prompt (Router>). Type enable and the
password to enter enable mode:
Router> enable
Password:
Configuration changes can be made only in enable mode. The prompt changes to the
privileged EXEC (enable) prompt (Router#):
Router#
Step 4 Enter the command config terminal to enter configuration mode:
Router# config terminal
Router(config)#
The router enters global configuration mode, indicated by the Router(config)# prompt.
Step 5 If you have not configured the router before, or want to change the configuration,
configure global parameters, passwords, network management, and routing protocols. In
this example, IP routing, AppleTalk routing, and Internetwork Packet Exchange (IPX)
routing are all enabled:
Router(config)# ip routing
Router(config)# appletalk routing
Router(config)# ipx routing
For complete information about global configuration commands, refer to the Cisco IOS
configuration guides and command references.
Step 6 Enter the controller t1 command to select the CT1/PRI interface to configure. For
example, to configure a T1 interface in slot 1 and unit 0, enter the following command:
Router(config)# cont t1 1/0
Step 7 Specify the clock source for the module. The clock source command determines which
end of the circuit provides clocking:
Router(config-controller)# clock source line
Note Theclock source should be set to use internal clockingonly for testing the network
or if the full T1 line is used as the channel group. Only one end of the T1 line should be
set to internal.
Step 8 Specify the framing type:
Router(config-controller)# framing esf
Step 9 Specify the line code format:
Router(config-controller)# linecode b8zs
Router(config-controller)#
%CONTROLLER-3-UPDOWN: Controller T1 1, changed state to up
Router(config-controller)#

1-Port and 2-Port ISDN-PRI Network Module Configuration Note 19
Configuring the PRI Interfaces
Step 10 Specify the channel group and time slots to be mapped. The command shown sets the
channel group to 0 and selects time slots 1, 3 through 5, and 7 for mapping.
Router(config-controller)# channel-group 0 timeslots 1,3-5,7
Router(config-controller)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/0:0, changed state to down
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/0:0, changed state to up
Router(config-controller)#
Router(config-controller)#
Step 11 After you define T1 channel groups, you can configure each channel group as a virtual
serial interface. Specify the CT1/PRI interface, unit number, and channel group to
modify, as in the following example:
Router(config-controller)# int serial 1/0:0
Step 12 Assign an IP address and subnet mask to the interface using the ip address command,
substituting the IP address and subnet mask for your site:
Router(config-if)# ip address 1.1.15.1 255.255.255.0
Router(config-if)#
Step 13 Add any configuration commands needed to enable routing protocols or adjust the
interface characteristics. Refer to the Cisco IOS configuration guides and command
references for more information.
Step 14 If your router has more than one CT1/PRI interface, enter the exit command to return to
the Router(config)# prompt. Repeat Step 6 through Step 13 of this procedure to configure
the next CT1/PRI interface.
Step 15 By default, the router allocates 25 percent of dynamic random-access memory (DRAM)
to shared memory (used for data transmitted or received by network modules and WAN
interface cards). If your router includes multiple ISDN PRI interfaces, you must increase
the amount of shared memory by entering the memory-size iomem command. The
following example increases shared memory from 25 percent to 40 percent:
Router(config)# memory-size iomem 40
Note For further information about the memory-size iomem command, refer to the
Cisco IOS configuration guides and command references.
Step 16 When you are finished configuring interfaces, exit configuration mode and return to the
enable prompt by pressing Ctrl-Z. To see the current operating configuration, including
any changes you just made, enter the show running-config command:
Router# show running-config
To see the configuration currently stored in NVRAM, enter the command show
startup-config at the enable prompt.
Router# show startup-config

20 1-Port and 2-Port ISDN-PRI Network Module Configuration Note
Configuring the PRI Interfaces
Step 17 The results of the show running-config andshow startup-configcommands differ from
each other if you have made changes to the configuration, but have not yet written them
to NVRAM. To write your changes to NVRAM, making them permanent, enter the
command copy running-config startup-config at the enable prompt:
Router# copy running-config startup-config
Building configuration. . .
[OK]
Router#
The router is now configured to boot in the new configuration.
Configuring E1 Interfaces
The following procedure can be used to configure a new CE1/PRI module (balanced or unbalanced)
or to change the configuration of an existing module.
To enter configuration mode, follow this procedure:
Step 1 Connect a console to the router. If you need instructions for connecting a console, refer
to the installation chapter of your router installation and configuration guide. Power up
the router.
Step 2 If the current configuration is no longer valid, after about a minute you see the following
prompt:
Would you like to enter the initial dialog? [yes]:
Answer no. You now enter the normal operating mode of the router.
Note If the current configuration is valid, you enter the normal operating mode
automatically.
Step 3 After a few seconds you see the user EXEC prompt (Router>). Type enable and the
password to enter enable mode:
Router> enable
Password:
Configuration changes can be made only in enable mode. The prompt changes to the
privileged EXEC (enable) prompt (Router#):
Router#
Step 4 Enter the command config terminal to enter configuration mode:
Router# config terminal
Router(config)#
The router enters global configuration mode, indicated by the Router(config)# prompt.