Cisco IAD2420 Series Integrated Access Devices Software Configuration Guide
Configuration Using Command Line Interface
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Table Of Contents

Configuration Using the Command-Line Interface

Configuring Access and Security Parameters

Host Name, Enable Secret Password, and Time Stamps

Local AAA Security

Log-in Banner

Configuring WAN and User-Side Interfaces

Setting the Ethernet Port IP Address

Configuring a T1-WAN Port for a WAN Connection

Configuring a T1-PBX Port

Verifying the T1 Controller Configuration

Performing T1 Controller Loopback Diagnostics

Configuring TDM Cross-Connect (Data Pass-Through)

Configuring ATM Interface (T1-WAN Port and ADSL/SHDSL Port)

Default Configuration

Verifying Your ATM Interface Configuration

Verifying the SHDSL Controller Configuration

Configuring Basic Settings for the Serial Port

Configuring Voice Ports

Configuring Analog Voice Ports

Configuring Digital Voice Ports

Tuning Analog and Digital Voice-Port Settings

Verifying Your Analog or Digital Voice-Port Configuration

Configuring Basic IP Settings

Configuring Synchronized Clocking

Clocking Configuration Procedure

Configuring Clock Recovery Through a T1 Port

Configuring a T1 Controller for Loop Timing

Configuring Clock Recovery Through the Serial Port

Clock Recovery Through an ADSL or SHDSL Port

Configuring Internal Clock

Configuring a Hierarchy of Backup Clock Sources

Configuring Backup Clock Sources

Verifying Your Configuration

Saving Configuration Changes


Configuration Using the Command-Line Interface

This chapter describes how to configure the Cisco IAD manually, and includes procedures for configuring features and interfaces that are not covered in the setup command facility. Before proceeding with manual configuration, read "Cisco IOS Software Basics," to familiarize yourself with the command-line interface (CLI).

This chapter contains the following sections:

•Configuring Access and Security Parameters

•Configuring WAN and User-Side Interfaces

•Configuring Basic IP Settings

•Configuring Synchronized Clocking

•Verifying Your Configuration

•Saving Configuration Changes

Configuring Access and Security Parameters

Configure basic access and security parameters:

•Host Name, Enable Secret Password, and Time Stamps

•Local AAA Security

•Log-in Banner

Tip Periodically save the configuration by using the copy running-config startup-config command.

Host Name, Enable Secret Password, and Time Stamps

Assign a host name, specify an enable secret password, and turn on time stamps:

•A host name allows you to identify the various network devices.

•The enable secret password is encrypted and cannot be read when you enter show running-config. Be sure to write the password down in a secure location.

•Time stamps help you trace debug outputs that are used for testing. Precise knowledge of event timing is useful for examining background processes.

Step 1 Enter the following commands in global configuration mode: 

Router(config)# hostname hostname

Router(config)# enable secret yourpassword

Router(config)# service password-encryption

Router(config)# service timestamps debug datetime msec

Router(config)# service timestamps log datetime msec

Router(config)#

Note The enable password command is an obsolete command. Do not use it.

Step 2 Exit from global configuration mode: 

Router(config)# exit

Step 3 Disable the privileged EXEC access: 

Router# disable

Step 4 Reenter the privileged EXEC mode with the enable secret password. The show privilege command shows the current security privilege level. Level 15 is privileged EXEC. 

Router> enable

Password:

Router# show privilege

Current privilege level is 15

Router#

Local AAA Security

For information about configuring authentication, authorization, and accounting (AAA) for controlling user access, see the Cisco IOS Security Configuration Guide for your Cisco IOS software release.

Log-in Banner

For information on creating a log-in banner see the "Managing Connections, Menus, and System Banners" section under "Cisco IOS User Interfaces" in the Cisco IOS Configuration Fundamentals Configuration Guide for your Cisco IOS software release.

Configuring WAN and User-Side Interfaces

Complete the following tasks to place the Cisco IAD into service with an initial configuration that supports the installed user-side and wide-area network (WAN) interfaces:

•Setting the Ethernet Port IP Address

•Configuring a T1-WAN Port for a WAN Connection

•Configuring a T1-PBX Port

•Verifying the T1 Controller Configuration

•Performing T1 Controller Loopback Diagnostics

•Configuring TDM Cross-Connect (Data Pass-Through)

•Configuring ATM Interface (T1-WAN Port and ADSL/SHDSL Port)

•Configuring Basic Settings for the Serial Port

•Configuring Voice Ports

•Verifying Your Analog or Digital Voice-Port Configuration

When you have completed the uplink and user interfaces, your Cisco IAD is ready to configure for specific functions. For specific configuration procedures see the appropriate documentation on CCO for the Cisco IOS software release installed on your Cisco IAD:

•For basic IP configuration, see the "Configuring Basic IP Settings" section of this guide; see also the Cisco IOS IP and IP Routing Configuration Guide.

•For Voice over IP configuration, see the "Configuring Voice over IP" section of the Cisco IOS Multiservice Applications Configuration Guide.

•For basic ATM configuration, see the "Configuring ATM" section of the Cisco IOS Wide-Area Networking Configuration Guide.

•For Voice over ATM configuration procedures, see the "Configuring Voice over ATM" section of the Cisco IOS Multiservice Applications Configuration Guide.

•For new features associated with a software release, see the new feature documentation for the Cisco IOS software release installed on your Cisco IAD.

Setting the Ethernet Port IP Address

Complete this procedure to set an IP address for the Ethernet port.

Note The Ethernet port (yellow) must be connected to a live Ethernet network using a standard Ethernet cable with RJ-45 connectors.

After the Ethernet port is configured, you can either configure the Cisco IAD remotely through a Telnet connection, or you can continue using the console or auxiliary port.

 
Command
Purpose

Step 1 

Router> enable

Enables the privileged EXEC mode.

Step 2 

Router# configure terminal

Enters global configuration mode.

Step 3 

Router(config)# interface Ethernet 0

Enters the interface configuration mode.

Step 4 

Router(config-if)# ip address IP-address subnet-mask

Enters the IP address and subnet mask you want for your Ethernet port.

Step 5 

Router(config-if)# no shutdown

Activates the Ethernet port.

Step 6 

Router(config-if)# exit

Returns to global configuration mode.

Step 7 

Router(config)# line vty 0 4

Enters line configuration mode.

Step 8 

Router(config-line)# password password

Sets password for remote access to the Cisco IAD.

Step 9 

Router(config-line)# end

Returns to privileged EXEC mode.

Step 10 

Router# copy system:running-
config nvram:startup-config

Saves the configuration by copying the running configuration to NVRAM.

Step 11 

Router# Destination filename [startup-config]? Press Return

Confirms the destination filename.

Configuring a T1-WAN Port for a WAN Connection

Cisco IAD2421 series IADs have a T1-WAN port that supports balanced T1 per ANSI T1.403 and has a built-in CSU/DSU.

To configure the basic T1 controller settings to support Asynchronous Transfer Mode (ATM), Point-to-Point Protocol (PPP), high-level data link control (HDLC), or Frame Relay (FR), complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# controller t1 0

Enters controller configuration mode and enter the controller number. The controller number for a T1-WAN port is 0.

Step 2 

Router(config-ctrl)# clock source {internal | line | loop-timed}

Configures the controller clock source for a DS1 link. The default is line.

If the clock source is a network device attached to the T1 port that you are configuring now, select the line option. For any other clock source (internal or a network device attached to any other port) select the internal option. Only one controller in a Cisco IAD can receive clock from an external line.

Step 3 

Router(config-ctrl)# description line

Enters a description of the controller, such as the destination or its application. The description can be as many as 80 characters long.

Step 4 

Router(config-ctrl)# cablelength
short {133 | 266 | 399 | 533 | 655}


or

Router(config-ctrl)# cablelength
long {gain26 | gain36} {-15db |
-22.5db | -7.5db | 0db}

Configures the cable length if the length is 655 feet or shorter.

or

Configures the receive gain and transmit attenuation if the cable length is longer than 655 feet.

Step 5 

Router(config-ctrl)# framing
{sf | esf}

If necessary, changes the DS1 link framing format. The default is SuperFrame (sf).

Step 6 

Router(config-ctrl)# linecode
{ami | b8zs}

If necessary, change the line encoding format for the DS1 link. The default is ami.

Step 7 

Router(config-ctrl)# no shutdown

Activates the T1 controller.

Step 8 

Router(config-ctrl)# exit

Exits controller configuration mode.

Step 9 

Router(config)# exit

Exits global configuration mode.

Step 10 

Router# show controller T1 0

Verifies the controller configuration.

For additional information about configuring specific features, see the following references:

•PPP—Cisco IOS Dial Services Configuration Guide: Terminal Services

•HDLC—Cisco IOS Interface Configuration Guide

•Frame Relay—Cisco IOS Wide-Area Networking Configuration Guide

For information about obtaining the referenced documentation, see the "Obtaining Documentation" section.

Configuring a T1-PBX Port

Cisco IAD2420 series IADs for digital PBX interface have a T1-PBX port with a balanced T1 interface per ANSI T1.403, and they contain a built-in CSU/DSU. The T1-PBX port supports 24 digital voice lines.

To configure the basic T1 controller settings on the T1-PBX port, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# controller t1 1

Enters controller configuration mode and enter the controller number. The controller number for a T1-PBX port is 1.

Step 2 

Router(config-ctrl)# clock source {internal | line | loop-timed}

Configures the controller clock source for a DS1 link. The default is line.

If the clock source is a network device attached to the T1 port that you are configuring now, select the line option. For any other clock source (internal or a network device attached to any other port) select the internal option. Only one controller in a Cisco IAD can receive clock from an external line.

Step 3 

Router(config-ctrl)# description line

Enters a description of the controller, such as the destination or its application. The description can be as many as 80 characters long.

Step 4 

Router(config-ctrl)# cablelength
short {133 | 266 | 399 | 533 | 655}


or

Router(config-ctrl)# cablelength
long {gain26 | gain36} {-15db |
-22.5db | -7.5db | 0db}

Configures the cable length if the length is 655 feet or shorter.

or

Configures the receive gain and transmit attenuation if the cable length is longer than 655 feet.

Step 5 

Router(config-ctrl)# framing
{sf | esf}

If necessary, changes the DS1 link framing format to match the PBX format. The default is SuperFrame (sf).

Step 6 

Router(config-ctrl)# linecode
{ami | b8zs}

If necessary, changes the line encoding format for the DS1 link to match the PBX format. The default is ami.

Step 7 

Router(config-ctrl)# no shutdown

Activates the T1 controller.

Step 8 

Router(config-ctrl)# exit

Exits controller configuration mode.

Step 9 

Router(config)# exit

Exits global configuration mode.

Step 10 

Router# show controller T1 1

Verifies the controller configuration.

Verifying the T1 Controller Configuration

To verify that a controller is up and no alarms or errors are detected, enter the show controller T1 command in EXEC mode: 

Router# show controller T1 {0 | 1}

Error counters are recorded over a 24-hour period in 15-minute intervals. In verifying initial controller configuration, the relevant data is in the current interval.

Example output for a T1-WAN or T1-PBX port 

Router# show controller T1 0 or show controller T1 1

T1 is up.

  Applique type is Channelized T1

  Cablelength is short

  No alarms detected.

  Framing is ESF, Line Code is AMI, Clock Source is Line.

  Data in current interval (240 seconds elapsed):

     0 Line Code Violations, 0 Path Code Violations

     0 Slip Secs, 0 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins

     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 0 Unavail 
Secs

  Data in Interval 1:

     0 Line Code Violations, 8 Path Code Violations

     11 Slip Secs, 26 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins

     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 26 
Unavail Secs

  Total Data (last 1 15 minute intervals):

     0 Line Code Violations, 8 Path Code Violations,

     11 Slip Secs, 26 Fr Loss Secs, 0 Line Err Secs, 0 Degraded Mins,

     0 Errored Secs, 0 Bursty Err Secs, 0 Severely Err Secs, 26 
Unavail Secs

Router#

Performing T1 Controller Loopback Diagnostics

To perform T1 controller loopback diagnostics as needed, complete the following steps in controller configuration mode:

 
Command
Purpose

Step 1 

Router(config-controller)# loopback {local | line | payload}

Places the T1 controller into loopback mode.

Step 2 

Router(config-controller)# no loopback {local | line | payload}

When you are finished performing the loopback diagnostics, disables the loopback mode.

After each controller is set up correctly, clear the counters and look for ongoing line violations and errors. To do this, enter the clear controller command followed by the show controller command: 

Router# clear controller t1 0

Router# show controller t1 0


Router# clear controller t1 1

Router# show controller t1 1

In the display output, focus on the data in the current interval. Error counters do not increase if the controller is configured correctly.

Note The clear controller t1 command does not reset or bring down the controller. The only action is to clear the counters.

Table 4-1 provides a list of T1 alarm conditions and descriptions relevant to the Cisco IAD.

Table 4-1 Alarm Conditions

Alarm
Description

CRC Errors

Occur only in ESF format when a CRC bit has an error.

Excessive CRC Error Indication (ECRCEI)

Reported in ESF format when 32 of any 33 consecutive CRCs are in error.

Out of Frame (OOF)

Occurs when the framing pattern for a T1 line has been lost, and data cannot be extracted. This is a red alarm. In SF and ESF formats, OOF occurs when any two of four consecutive frame-synchronization bits are in error.

Loss of Signal (LOS)

Occurs when 175 consecutive 0s are detected in the MC. This is a red alarm. The signal is recovered if the density of 1s reaches 12.5%. The recovery happens when four 1s are received within a 32-bit period.

Remote Frame Alarm (RHEA)

Indicates that an OOF framing pattern occurred at the remote end. This is a yellow alarm.

Alarm Indication Signal (AIS)

Indicates to the remote end a loss of the received signal. This is a blue alarm. AIS occurs when a stream of 1s is received.

Loop Back

Indicates that a remotely initiated loopback (from the network) is in progress.

Errored Seconds

Depending on the framing format, indicates OOF conditions, frame slip conditions, or error events.

For SF, errored seconds reports the number of seconds the frame was in the OOF or slip condition. For ESF, errored seconds reports error events in seconds.

Bursty Errored Seconds

Reports CRC error conditions in seconds (ESF format only).

Severely Errored Seconds

Reports error events or frame slip conditions in seconds.


For more information about controllers, see the "Channelized E1 and Channelized T1 Setup Commands" section of the Dial Solutions Command Reference for your release of Cisco IOS software.

Configuring TDM Cross-Connect (Data Pass-Through)

The Time Division Multiplexing (TDM) cross-connect function allows you to create one or more TDM groups on a controller. Each TDM group is a block of contiguous or noncontiguous 64-kbps timeslots that function as a clear channel.

You can cross-connect TDM groups as follows:

•Between two controllers

•Between serial port 0 and controller T1 0 or T1 1

To configure TDM cross-connect, complete the following steps, beginning in controller configuration mode:

 
Command
Purpose

Step 1 

Router(config-controller)# tdm-group tdm-group-no timeslot timeslot-list [type {e&m | fxs loop-start | fxs ground-start | fxo loop-start | fxo ground-start}]

Assigns a tag number to identify the TDM group, assigns one or more timeslots to the TDM group, and specify an interface type for voice traffic.

If you are configuring cross-connect for data traffic only, do not specify the type option. The type option only applies if the mode cas command is enabled.

Step 2 

Router(config-controller)# exit

Exits controller configuration mode.

Step 3 

For TDM cross-connect between two controllers:

Router(config)# cross-connect tag controller-1 tdm-group-no controller-2 tdm-group-no


For TDM cross-connect between a controller and a UIO serial port:

Router(config)# cross-connect tag interface-serial controller tdm-group-no

Assigns a tag to identify the TDM cross-connection, and specify the data streams to be cross-connected:

•TDM group to TDM group (2 controllers)

or

•Serial interface to TDM group (1 serial port and 1 controller)

Note For TDM cross-connect between a UIO serial port and a controller, encapsulation clear-channel must be configured on the serial port.

 

Configuring ATM Interface (T1-WAN Port and ADSL/SHDSL Port)

Default Configuration

If your Cisco IAD has an ADSL, SHDSL, or T1-WAN port, a default ATM configuration is automatically enabled when you enter the mode atm controller command. The default ATM configuration has the following operating parameters:

•ADSL or SHDSL port only

–Operating mode is auto—The ADSL or SHDSL interface operates in the mode specified by the remote DSL access multiplexer (DSLAM).

•T1-WAN port and ADSL or SHDSL port

–Maximum VPIs per VCI (atm vc-per-vc)—1024

–No IP address

–ATM UNI Version 3.0 is assigned

–ATM ILMI keepalive is disabled

–No ATM PVCs are configured

To configure the ATM interface parameters for your application, you need the following information:

•IP addresses and subnet masks

•Network numbers

•Zones

•VPI/VCI numbers

•Any other information related to the routing protocol

To enter an ATM configuration, complete the following steps, beginning in global configuration mode:

 
Command
Purpose

Step 1 

For a T1-WAN port:

Router(config)# controller t1 0


For an SHDSL port:

Router(config)# controller shdsl 0


For an ADSL port:

Go to step 6.

Enters controller configuration mode and the controller number.

Step 2 

Router(config-ctrl)# mode atm

Enables ATM encapsulation and create logical ATM interface 0. Controller framing is automatically set to Extended SuperFrame (ESF). The linecode is automatically set to B8ZS.

Step 3 

For SHDSL ports only:

Router(config-ctrl)# annex {a | b}

Specifies the regional operating parameters. Enter a for North America and b for Europe. The default is a.

Step 4 

For SHDSL ports only:

Router(config-ctrl)# line-rate {auto | rate}

Specifies the DSL line rate for the SHDSL port. The range is 72 to 2312 kbps. The default is auto (negotiated between the SHDSL port and the DSLAM)

Note If different DSL line rates are configured at opposite ends of the DSL uplink, the actual DSL line rate is always the lower rate.

 

Step 5 

Router(config-ctrl)# exit

Exits from controller configuration mode.

Step 6 

Router(config)# interface atm 0

Enters ATM configuration mode for interface ATM 0.

Step 7 

Router(config-if)# ip-address IP-address

(Optional) Assigns an IP address to the ADSL or SHDSL ATM interface.

Step 8 

Router(config-if)# atm uni-version version-number

(Optional) Specifies an ATM user network interface (UNI) version number.

Step 9 

Router(config-if)# atm ilmi-keepalive seconds

(Optional) Enables Integrated Local Management Interface (ILMI) keepalives.

If you enable ILMI keepalives without specifying the seconds, the default time interval is 3 seconds.

Step 10 

Router(config-if)# pvc [name] vpi/vci

Enters atm-virtual-circuit (interface-atm-vc) configuration mode, and configure a new ATM PVC by assigning a name (optional) and VPI/VCI numbers.

The default traffic shaping is UBR; the default encapsulation is AAL5+LLC/SNAP.

Step 11 

Router(config-if-vc)# protocol ip IP-address

(Optional) Enables IP connectivity and create a point-to-point IP address for the VC.

Step 12 

Router(config-if-vc)# vbr-rt peak-rate average-rate burst

(Optional) Configures the PVC for real-time variable bit rate (VBR) traffic shaping.

•Peak rate—peak information rate (PIR)

For SHDSL ports, set the peak rate for the trained line rate minus 8 kbps.

•Average rate—average information rate (AIR)

•Burst—burst size in cells

Step 13 

Router(config-if-vc)# encapsulation {aal1 | aal2 | aal5ciscoppp | aal5mux | aal5nlpid | aal5snap}

(Optional) Configures the ATM adaptation layer (AAL) and encapsulation type.

•aal1 for AAL1

•aal2 for AAL2

•aal5ciscoppp for Cisco PPP over AAL5

•aal5mux for AAL5+MUX

•aal5nlpid for AAL5+NLPID

•aal5snap for AAL5+LLC/SNAP (the default)

Step 14 

Router(config-if-vc)# exit

Exits from interface-atm-vc configuration mode.

Step 15 

Repeat steps 10 through 14 for each additional ATM PVC to be configured.

Configures any additional ATM PVCs.

Step 16 

For an ADSL port:

Router(config-if)# dsl operating-mode {ansi-dmt | auto itu-dmt | splitterless}


For an SHDSL port or a T1-WAN port:

Go to step 17.

Configures the ADSL interface to operate in a specified mode:

•ansi-dmt—ANSI full rate mode per T1.413 (ITU G dmt Issue 1)

•auto—Automatic detection mode

•itu-dmt—ITU full rate mode (ITU G dmt Issue 1)

•splitterless—G.lite mode per ITU g.992.2

Step 17 

Router(config-if)# no shutdown

Activates the ATM interface.

Step 18 

Router(config-if)# exit

Exits from ATM interface configuration mode.

Step 19 

Router(config)# exit

Exits from global configuration mode.

Verifying Your ATM Interface Configuration

To verify the ATM interface configuration, enter the show interface atm 0 EXEC command. The following example shows a typical output from the show interface atm 0 command: 

Router# show interface atm 0

ATM0 is up, line protocol is up

  Hardware is PQUICC Atom1

  MTU 1500 bytes, sub MTU 1500, BW 2304 Kbit, DLY 20000 usec,

     reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation ATM, loopback not set

  Keepalive not supported

  Encapsulation(s):, PVC mode

  512 maximum active VCs, 4 current VCCs

  VC idle disconnect time:300 seconds

  Last input never, output never, output hang never

  Last clearing of "show interface" counters never

  Input queue:0/75/0/0 (size/max/drops/flushes); Total output drops:0

  Queueing strategy:None

  5 minute input rate 0 bits/sec, 0 packets/sec

  5 minute output rate 0 bits/sec, 0 packets/sec

     20486 packets input, 368419 bytes, 0 no buffer

     Received 0 broadcasts, 0 runts, 0 giants, 0 throttles

     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort

     0 packets output, 0 bytes, 0 underruns

     0 output errors, 0 collisions, 0 interface resets

     0 output buffer failures, 0 output buffers swapped out

Router#

Verifying the SHDSL Controller Configuration

To verify the SHDSL controller status and view the statistics, enter the show controller shdsl 0 EXEC command. The following example shows a typical output from the show controller shdsl 0 command: 

Router# show controller shdsl 0


 SHDSL 0 controller UP

 SLOT 3:Globespan xDSL controller chipset

 Frame mode:ATM

 Configured Line rate:Auto

 Line Re-activated 1 times after system bootup

 LOSW Defect alarm:None

 CRC per second alarm:None

 Line termination:CPE

 FPGA Revision:9


    Current 15 min CRC:0

    Current 15 min LOSW Defect:0

    Current 15 min ES:0

    Current 15 min SES:0

    Current 15 min UAS:0


    Previous 15 min CRC:0

    Previous 15 min LOSW Defect:0

    Previous 15 min ES:0

    Previous 15 min SES:0

    Previous 15 min UAS:0


 Chipset Version: 1

 Firmware Version: R1.0

 Modem Status: Data

 Line rate: 2312 Kbps

 Framer Sync Status:In Sync

 Rcv Clock Status:In the Range

 Loop Attenuation: 3.1250 dB

 Transmit Power: 7.5 dB

 Receiver Gain: 18.420 dB

 SNR Sampling: 42

 Last Fail Mode: No Failure

Router#

Configuring Basic Settings for the Serial Port

To display the default configuration for serial port 0, enter the show interface serial command.

Router# show interface serial


To configure basic settings for the serial port, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# network-clock
base-rate {56k | 64k}

Specifies a network clock base rate.

Step 2 

Router(config)# interface serial 0

Enters serial interface configuration mode.

Step 3 

Router(config-if)# clock rate
network-clock rate

Configures the serial interface phase-lock-loop clock speed. The range is 300 to 2420 kbps. There is no default.

Step 4 

Router(config-if)# no shutdown

Activates the serial port.

Step 5 

Router(config-if)# exit

Exits interface configuration mode.

Step 6 

Router(config)# exit

Exits configuration mode.

Step 7 

Router# show interface serial

Displays the serial port configuration to verify the new settings.

Configuring Voice Ports

This section has separate procedures for analog and digital voice ports. Use the analog procedure to configure analog FXS and FXO voice ports. Use the digital procedure to configure the T1 digital voice port.

Verifying Voice-Port Configuration

Before entering voice-port configuration mode, enter: 

Router> show voice port summary

This command brings up a list of the existing voice ports with their slot/port numbers, signaling types, and status.

Note A Cisco IAD2420 series IAD can have 8 or 16 analog FXS voice ports, or 16 analog FXS and 8 analog FXO voice ports, or as many as 24 digital voice ports. Individual subscriber lines on the digital voice port do not exist unless you create at least one DS0 group.

To see the complete current configuration of an existing voice port, enter a show voice port command:

•For analog voice ports— 

Router> show voice port slot/port

•For digital voice ports— 

Router> show voice port controller/DS0-group

Table 4-2 summarizes the physical and logical characteristics of the Cisco IAD voice ports.

Table 4-2 Voice Port Types and Identification

Cisco IAD Model
Voice Interface Type
Voice-Port Identification:

IAD242x-8

Analog FXS, on-premise

1/1 through 1/8

IAD242x-16

Analog FXS, on premise

1/1 through 1/16

IAD242x-16FXS8FXO

Analog FXS, off-premise

Analog FXO

1/1 through 1/16

1/17 through 1/24

IAD242x-1T1

Digital: To network (WAN)

0:0 through 0:23

IAD242x-1T1

Digital: To PBX

1:0 through 1:23


Note The voice-port number designations start with 1. Unlike serial-port interfaces and interfaces on other Cisco products, there is no port 0 for voice ports.

Configuring Analog Voice Ports

Cisco IAD2420 series IADs with analog voice chassis can have 8, 16, or 24 analog voice ports, with slot/port identification as follows:

•Cisco IAD242x-8FXS chassis—8 FXS, on-premise, voice ports numbered 1/1 through 1/8

•Cisco IAD242x-16FXS chassis—16 FXS, on-premise, voice ports numbered 1/1 through 1/16

•Cisco IAD242x-16FXS8FXO chassis—16 FXS, off-premise, voice ports numbered 1/1 through 1/16, and 8 FXO voice ports numbered 1/17 through 1/24

To configure or change the basic analog voice-port settings, complete the following steps, as required, beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# voice-port slot/port

Enters voice-port configuration mode, and specify the voice port that you want to configure by entering the logical slot number and port number (see Table 4-2). The commands affect only the voice port you specify here.

Step 2 

Router(config-voiceport)# codec
{g729r8 | g729ar8 | g726r32 |
g711alaw | g711ulaw}

Specifies a nondefault voice compression codec. The g729ar8 value is the default.

Simultaneously active, on-net, voice calls support by codecs:

•g729ar8—24 calls maximum

•g729r8—12 calls maximum

Nominal data rates for compression modes:

•g729r8 and g729ar8—8 kbps

•g726r32—32 kbps

•g711alaw and g711ulaw—64 kbps

Step 3 

Router(config-voiceport)# connection {tie-line | plar | plar opx} string

Configures a voice-port connection mode.

If the connection is to a PBX, use the tie-line option.

If the connection is for Private Line Auto Ringdown (PLAR) use the plar option.

If the connection is for PLAR Off-Premises eXtension (OPX), use the plar-opx option. With this option, the local voice port provides a local response before the remote voice port receives an answer, and FXO interfaces do not answer until the remote side answers.

Step 4 

Router(config-voiceport)# signal
{loop-start | ground-start | did {wink-start | immediate | delay-dial}}

Changes the signaling type for the voice port. The default is loop-start.

Step 5 

Router(config-voiceport)# dial-type {pulse | dtmf}

(FXO only) Changes the transmit dial type. The default is dtmf.

Step 6 

Router(config-voiceport)# cptone country

Configures the voice port for the local territory call progress tone setting. The call progress tone setting determines the settings for dialtone, busytone, and ringback tone.

The default for this command is northamerica. For a list of supported countries, see the Cisco IOS Voice, Video, and Fax Command Reference for the Cisco IOS software release installed on your Cisco IAD.

Step 7 

Router(config-voiceport)# no shutdown

Activates the voice port. You should activate only those voice ports that you plan to use.

Step 8 

Router(config-voiceport)# description string

Enters a description of the location or use of this voice port. You can enter as many as 255 characters.

Step 9 

Exit from voice-port configuration mode and repeat Steps 1 through 8 for the remaining analog voice ports.

Configures any required voice ports.

Note If you are not going to use a voice port, shut it down to conserve bandwidth.

To configure tuning options for analog voice ports, see the "Tuning Analog and Digital Voice-Port Settings" section.

To configure dial peers, see the applicable voice service configuration section of the Cisco IOS Multiservice Applications Configuration Guide for the Cisco IOS software release installed on your Cisco IAD.

Configuring Digital Voice Ports

Cisco IAD2420 series IADs with digital voice chassis (Cisco IAD242x-1T1) have a T1-PBX port that supports a balanced T1 interface with a digital PBX. The T1-PBX interface supports as many as 24 voice lines (DS0s), with controller:DSO-group identification of 1:0 through 1:23.

To configure the basic T1 controller and digital voice port settings on the T1 PBX port, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# controller t1 1

Enters controller configuration mode for controller 1(the trunk controller for the T1-PBX port).

Step 2 

Router(config-controller)# mode
{cas | ccs cross-connect | ccs frame-forwarding}

Enters CAS configuration mode and configure the T1 trunk to support signaling that matches the PBX signaling type:

•cas—Channel-associated signaling

•ccs cross-connect—CCS cross-connect for bearer channels

•ccs frame-forwarding—CCS transparent signaling

Step 3 

Router(config-controller-cas)# ds0-group  ds0-group-no  timeslots timeslot-list type {e&m-immediate | e&m-delay | e&m-wink |
fxs-ground-start | fxs-loop-start | fxo-ground-start | fxo-loop-start}

Creates a DS0 group on the T1 trunk. A DS0 group can contain from 1 to 24 timeslots numbered from 0 to 23.

When configuring a DS0 group for a T1 line to a PBX, make sure that the timeslot numbers match the channels on the PBX. Contact the PBX administrator to determine which channels to use.

Timeslots with identical voice-port configuration can be assigned to one DS0 group.

Timeslots with nonidentical voice-port configurations must be assigned to different DS0 groups.

Note The maximum number of timeslots available in a T1 is 24. They can be assigned to one DS0 group, or they can be assigned to as many as 24 DS0 groups within the T1.

Step 4 

Repeat Step 3 for each additional DS0 group. After DS0 groups are defined, exit CAS configuration mode.

Configures additional DS0 groups on the T1 interface to the PBX. You can configure as many as 24 DS0 groups on a T1.

Step 5 

Router(config)# voice-port 1:DS0-group

Enters voice-port configuration mode, and specifies the voice port that you want to configure. The logical slot for these voice ports is always 1 (for controller 1). The logical port is 0 to 23, corresponding to the DS0 group. The following commands affect the timeslots in this logical voice port.

Step 6 

Router(config-voiceport)# dial-type {pulse | dtmf}

(FXO only) If this voice port supports rotary pulse dialing, changes the transmit dial type to pulse. The default is dtmf.

Step 7 

Router(config-voiceport)# compand-type {u-law | a-law}

Changes the companding if necessary. The default is u-law (the North American mu-law ITU-T PCM encoding standard). Specify a-law to use the European a-law ITU-T PCM encoding standard.

Step 8 

Router(config-voiceport)# no shutdown

Activates the voice port. You should activate only those voice ports that you plan to use.

Step 9 

Exit from voice-port configuration mode and repeat Steps 5 through 8 for the remaining digital voice ports.

Configures any required digital voice ports.

Note If you are not going to use a voice port, shut it down to conserve bandwidth.

To configure voice-port tuning options, see the "Tuning Analog and Digital Voice-Port Settings" section.

To configure dial peers, see the applicable voice service configuration section of the Cisco IOS Multiservice Applications Configuration Guide for the Cisco IOS software release installed on your Cisco IAD.

Tuning Analog and Digital Voice-Port Settings

In most cases the default values for voice port settings are sufficient. However, for specific configurations of analog and digital voice ports, you can tune the voice port settings as needed.

To tune voice-port settings, complete the following steps, as necessary, in voice-port configuration mode:

 
Command
Purpose

Step 1 

Router(config-voiceport)# input gain value

Configures the input gain—the dB of gain to be inserted on the receive side of the interface. The range is -6 to 14. The default is 0.

Step 2 

Router(config-voiceport)# output attenuation value

Configures the output attenuation—the dB of attenuation to be inserted on the transmit side of the interface. The range is 0 to 14. The default is 0.

Step 3 

Router(config-voiceport)# echo-cancel enable

Enables echo cancel coverage.

Step 4 

Router(config-voiceport)# echo-cancel coverage {8|16|24|32}

Configures the number of milliseconds the echo cancel will cover on a given signal. The default is 16.

Step 5 

Router(config-voiceport)# timeouts initial seconds

Configures the initial timeouts value for the voice port. This value specifies the number of seconds the system waits for the caller to input the first digit of the dialed digits. The range is 0 to 120. The default is 10.

Step 6 

Router(config-voiceport)# timeouts interdigit seconds

Configures the interdigit timeouts value for the voice port. This value specifies the number of seconds the system waits for the caller to dial each digit (after dialing the first digit). The range is 0 to 120. The default is 10.

Step 7 

If the voice-port dial type is DTMF, configure the DTMF timing values:

 
 

Router(config-voiceport)# timing digit milliseconds

Configures the DTMF digit signal duration in milliseconds. The range is 50 to 100. The default is 100.

 

Router(config-voiceport)# timing inter-digit milliseconds

Configures the DTMF interdigit signal duration in milliseconds. The range is 50 to 500. The default is 100.

 

If the voice-port dial type is pulse, configure the pulse timing values:

 
 

Router(config-voiceport)# timing pulse digit milliseconds

Configures the pulse digit signal duration in milliseconds. The range is 10 to 20. The default is 20.

 

Router(config-voiceport)# timing pulse inter-digit milliseconds

Configures the pulse inter-digit signal duration in milliseconds. The range is 100 to 1000. The default is 500.

Step 8 

Router(config-voiceport)# condition {tx-a-bit | tx-b-bit | tx-c-bit | tx-d-bit} {rx-a-bit | rx-b-bit | rx-c-bit | rx-d-bit} {on | off | invert}

(Digital voice ports only.) Configures the voice port to manipulate the bit patterns sent or received by the Cisco IAD to match expected patterns on a connected device.

Note Be careful not to destroy the information content of the bit pattern. For example, forcing the A-bit on or off will prevent FXO interfaces from being able to generate both an on-hook and off-hook state.

The show voice port command reports at the protocol level; however, the show controller command reports at the driver level. The driver is not notified of any bit manipulation using the condition command. As a result, the show controller command output does not account for the bit conditioning.

Step 9 

Router(config-voiceport)# ring frequency number

(FXS only) Specifies the ring frequency in hertz. The number options are 20, 25, 30, and 50. The default is 20.

Step 10 

Router(config-voiceport)# ring cadence {pattern01 | pattern02 | pattern03 | pattern04 | pattern05 | pattern06 | pattern07 | pattern08 | pattern09 | pattern10 | pattern11 | pattern12} | {define pulse interval}

(FXS only) Specifies the ring pulse and interval times as required for your location, if required.

The default is 2 seconds on and 4 seconds off—the default ring cadence for North America.

Options are as follows:

•pattern01—2 seconds on, 4 seconds off

•pattern02—1 second on, 4 seconds off

•pattern03—1.5 seconds on, 3.5 seconds off

•pattern04—1 second on, 2 seconds off

•pattern05—1 second on, 5 seconds off

•pattern06—1 second on, 3 seconds off

•pattern07—0.8 second on, 3.2 seconds off

•pattern08—1.5 seconds on, 3 seconds off

•pattern09—1.2 seconds on, 3.7 seconds off

•pattern10—1.2 seconds on, 4.7 seconds off

•pattern11—0.4 second on, 0.2 second off, 0.4 second on, 2 seconds off

•pattern12—0.4 second on, 0.2 second off, 0.4 second on, 2.6 seconds off

define—User-definable pattern. Each number pair specifies one ring-pulse and one interval. Enter 1 to 6 number pairs. The second number in the last pair specifies the interval between rings.

pulse—A number (1 or 2 digits) specifying ring pulse (on) time in 100-millisecond increments. The range is 1 to 50, for pulses of 100 to 5000 ms.

interval—A number (1 or 2 digits) specifying interval (off) time in 100-millisecond increments. The range is 1 to 50, for intervals of 100 to 5000 ms.

Step 11 

Router(config-voiceport)# disconnect-ack

(FXS only) Configures the FXS voice port to return an acknowledgment upon receipt of a disconnect signal. The FXS port will remove line power if the equipment on the FXS loop-start trunk disconnects first.

Step 12 

For analog FXS:

Router(config-voiceport)# impedance {600r | 600c | 900r | 900c | complex1 | complex2}


For analog FXO:

Router(config-voiceport)# impedance {600r | complex1}

Specifies the impedance for the analog voice port. The default for both FXS and FXO is 600r.

Options are as follows:

•600r—600 ohms resistive (real)

•600c—600 ohms complex (600 ohms in series with 2.15 µf)

•900r—900 ohms resistive (real)

•900c—900 ohms complex (900 ohms in series with 2.15 µf)

•complex1—220 ohms in series with the parallel combination of 820 ohms and 115 nf

•complex2—270 ohms in series with the parallel combination of 750 ohms and 150 nf

Step 13 

Router(config-voiceport)# ring number number

(FXO only) Specify the number of rings detected before the FXO port answers calls. The range is 1 to 10. The default is 1.

Step 14 

Router(config-voiceport)# timing guard-out milliseconds

(FXO only) Specifies the duration in milliseconds of the guard-out period to prevent this port from seizing a remote FXS port before the remote port detects a disconnect signal. The range is 300 to 3000. The default is 2000. A value of at least 600 is recommended.

Step 15 

Router(config-voiceport)# exit

Exit voice-port configuration mode.

Verifying Your Analog or Digital Voice-Port Configuration

You can test your analog or digital voice-port configuration by doing the following:

•Pick up the handset of an attached telephony device and check for dial tone.

•If you have dial tone, check for DTMF detection. If the dial tone stops when you dial a digit, the voice port is probably configured properly.

•Enter show voice port slot/port and show voice port summary to verify that the voice-port configuration is correct.

•Enter the show voice dsp EXEC command to verify the current status of all Digital Signaling Processor (DSP) voice channels.

•Enter the show voice call summary EXEC command to verify the call status for all voice ports.

Troubleshooting Tips

If you are having trouble connecting a call and you suspect the problem is associated with voice-port configuration, you can try to resolve the problem by performing the following:

•Ping the associated IP address to confirm connectivity. If you cannot successfully ping your destination, refer to the applicable IP configuration section in the Cisco IOS software configuration guide for the Cisco IOS release installed on your Cisco IAD:

–Cisco IOS IP and IP Routing Configuration Guide, Release 12.1

–Cisco IOS IP Configuration Guide, Release 12.2

•Enter show voice port to make sure that the voice port is enabled. You can display information for a single voice port, for all voice ports, or a summary report. If the voice port is offline, use the no shutdown command.

•Check the dial-peer configuration (as configured in the applicable voice service configuration section of the Cisco IOS Multiservice Applications Configuration Guide for the Cisco IOS software release installed on your Cisco IAD.

•Check the Frame Relay, ATM, or HDLC configuration.

Configuring Basic IP Settings

To tune IP routing behavior and domain-name services, complete the following steps:

Step 1 Optimize IP routing functions. Enter the following commands in global configuration mode: 

Router(config)# ip subnet-zero

Router(config)# no ip source-route

Router(config)# ip classless

Table 4-3 describes the previous commands.

Table 4-3 IP Routing Commands

Command
Purpose 
ip subnet-zero

Allows the use of 0 as a valid subnet. 

no ip source-route

Tightens security by ensuring that IP-header packets cannot define their own paths through the Cisco IAD. 

ip classless

Turns off traditional IP network class distinctions in the router: Class-A, Class-B, and Class-C.


Step 2 Configure IP domain-name options. Enter the following commands in global configuration mode: 

Router(config)# ip domain-lookup

Router(config)# ip host ip-hostname ip-address

Router(config)# ip domain-name word

Router(config)# ip name-server primary-ip-address

Router(config)# ip name-server secondary-ip-address

Table 4-4 describes the previous commands.

Table 4-4 Domain-Name Commands

Command
Purpose 
ip domain-lookup

Enables IP domain-name lookup. 

ip host aurora 172.22.100.9

Creates a local name-to-address map. When the Cisco IAD is not entered in a DNS server, this map is useful. 

ip domain-name the.doc

Tells the Cisco IAD how to qualify DNS look ups by appending a suffix to the end of each name that is looked up, for example the.doc. 

ip name-server 172.22.11.10

ip name-server 172.22.12.10

Specifies the primary and secondary name servers, which are used for mapping names to IP addresses.


Configuring Synchronized Clocking

This section is divided into the following subsections:

•Clocking Configuration Procedure

•Configuring a Hierarchy of Backup Clock Sources

Clocking Configuration Procedure

For voice and video applications, a single master clock source must be established. This section provides step-by-step procedures for configuring clocking without specifying a clock-source backup hierarchy.

Note Cisco IAD2423 series IADs for ADSL and Cisco IAD2424 series IADs for SHDSL recover clock from the DSL uplink by default. If a T1-PBX port is present in a Cisco IAD2423 series or Cisco IAD2424 series IAD, you must set the T1-PBX port to use internal clock.

If multiple sources of network clock are available to the Cisco IAD—for example, a controller configured for clock source line and the serial port configured for clock rate line—you must assign a different priority to each clock source; otherwise, multiple clock sources can cause clocking conflicts. See the "Configuring a Hierarchy of Backup Clock Sources" section.

This section includes the following procedures:

•Configuring Clock Recovery Through a T1 Port

•Configuring a T1 Controller for Loop Timing

•Configuring Clock Recovery Through the Serial Port

•Clock Recovery Through an ADSL or SHDSL Port

•Configuring Internal Clock

Configuring Clock Recovery Through a T1 Port

Figure 4-1 shows clock recovery from a network device connected to controller T1 0 (T1-WAN interface). Figure 4-2 shows clock recovery from a network device connected to controller T1 1 (T1-PBX interface).

Figure 4-1 Recovering Clock Through the T1-WAN Port

Figure 4-2 Recovering Clock Through the T1-PBX Port

To configure a T1 controller to recover external clock, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# controller T1 {0 | 1}

Enters controller configuration mode for the controller that you are configuring for external clock recovery.

Step 2 

Router(config-controller)# clock source line

Configures the controller to recover external clock.

Step 3 

Router(config-controller)# exit

Exits controller configuration mode.

Step 4 

Router(config)# controller T1 {0 | 1}

Enters controller configuration mode for the other controller, if it is installed.

Step 5 

Router(config-controller)# clock source {internal | loop-timed | line}

If the second controller is not a backup clock source, configures it to use internal (system) clock or loop timing.

If the second controller is a backup clock source, configures it to recover external (line) clock1 .

Step 6 

Router(config-controller)# exit

Exits controller configuration mode.

Step 7 

Router(config)# network-clock base-rate [56k | 64k]

Sets the network clock base rate for the serial ports: 56k for T1. The default is 56k.

Step 8 

Router(config)# interface serial 0

Enters interface configuration mode for serial port 0.

Step 9 

Router(config-if)# clock rate network rate

Specifies a clock rate for the serial port. The rate must be a multiple (up to 32x) of the value set with the network-clock base-rate command—in other words, n x 56000 or n x 64000, where n = 1 to 32.

Step 10 

Router(config-if)# exit

Exits interface configuration mode.

Step 11 

Router(config-if)# ctrl z

Returns to privileged EXEC mode.

Step 12 

Router# show network-clocks

Displays the network clock configuration.

1 Unless activated, a backup clock source automatically operates in loop-timed mode (although configured for external clock).

Configuring a T1 Controller for Loop Timing

A controller operates with loop timing under two conditions:

•When configured for loop timing with the clock source loop-timed command

•When configured as a backup clock source

Note Loop timing should be configured only in certain cases, for example, when the Cisco IAD is connected to two networks and they both provide clock. Do not configure a port for loop timing if there is no other source of external clock.

Figure 4-3 shows an example of a loop-timed controller T1 0.

Figure 4-3 Loop-Timed Controller T1 0 (T1-WAN Port)

To configure loop timing on a T1 controller, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# controller T1
{0 | 1}

Enters controller configuration mode for the controller that you are configuring for loop timing.

Step 2 

Router(config-controller)# clock source loop-timed

Configures the controller to use external clock from the receive line and transmit it back to the source.

Step 3 

Router(config-controller)# exit

Exits controller configuration mode.

Step 4 

Router(config)# controller T1
{0 | 1}

Enters controller configuration mode for the other controller, if it is installed.

Step 5 

Router(config-controller)# clock source line

Configures the other controller to recover external clock (line).

Step 6 

Router(config-controller)# exit

Exits controller configuration mode.

Step 7 

Router(config)# network-clock base-rate [56k | 64k]

Sets the network clock base rate for the serial ports: 56k for T1. The default is 56k.

Step 8 

Router(config)# interface serial 0

Enters interface configuration mode for the serial port.

Step 9 

Router(config-if)# clock rate network rate

Specifies a clock rate for the serial port. The rate must be a multiple (up to 32x) of the value set with the network-clock base-rate command—in other words, n x 56000 or n x 64000, where n = 1 to 32.

Step 10 

Router(config-if)# exit

Exits interface configuration mode.

Step 11 

Router(config-if)# ctrl z

Returns to privileged EXEC mode.

Step 12 

Router# show network-clocks

Displays the network clock configuration.

Configuring Clock Recovery Through the Serial Port

Figure 4-4 shows clock recovery from a network device connected to the serial port.

Figure 4-4 Recovering Clock Through the Serial Port

Note Network clock recovery over serial interfaces is possible through the serial port only in DTE mode, not in DCE mode.
Set the serial port to DTE by connecting it to a DTE cable.

Note If a Cisco IAD2420 series IAD has an ADSL port, the ADSL port is the first-priority clock source.

To configure the serial port to recover network clock, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# network-clock-select 1 serial 0

Configures the Cisco IAD to recover clock from the serial port (0).

The serial port must be set for DTE by a DTE cable.

Step 2 

Router(config)# network-clock base-rate {56k | 64k}

Sets the network clock base rate for the serial port: 56k for T1. The default is 56k.

Step 3 

Router(config)# interface serial 0

Enters interface configuration mode for the serial port.

Step 4 

Router(config-if)# clock rate line rate

Sets the clock recovery rate for the rate of the incoming clock. This value must be a multiple of 8000.

Step 5 

Router(config-if)# exit

Exits interface configuration mode.

Step 6 

Router(config)# controller
{T1 | E1} 0

Enters controller configuration mode for T1 0 if your Cisco IAD has a T1-WAN interface.

Step 7 

Router(config-controller)# clock source {internal | loop-timed | line}

If controller T1 0 is not a backup clock source, configures it to use internal (system) clock or loop timing.

If controller T1 0 is a backup clock source, configures it to recover external (line) clock1 .

Step 8 

Router(config-controller)# exit

Exits controller configuration mode.

Step 9 

If your Cisco IAD has a T1-PBX port:

Router(config)# controller T1 1


If your Cisco IAD has an analog voice user interface, go to step 11.


Enters controller configuration mode for T1 1.

Step 10 

If your Cisco IAD has a T1-PBX port:

Router(config-controller)# clock source {internal | loop-timed | line}

If controller T1 1 is not a backup clock source, configures it to use internal (system) clock or loop timing.

If controller T1 1 is a backup clock source, configures it to recover external (line) clock1.

Step 11 

Router(config)# ctrl z

Returns to privileged EXEC mode.

Step 12 

Router# show network-clocks

Displays the network clock configuration.

1 When not active, a backup clock source automatically operates in loop-timed mode (although configured for external clock).

Clock Recovery Through an ADSL or SHDSL Port

If a DSL port is present (ADSL or SHDSL) , the DSL port is the first-priority clock source. Figure 4-5 shows a Cisco IAD obtaining clocking from a DSL interface.

Figure 4-5 Recovering Clock Through ADSL or SHDSL Port

Configuring Internal Clock

Figure 4-6 shows use of the Cisco IAD internal clock generator.

Figure 4-6 Cisco IAD Internal Clock Generation

Note When using the Cisco IAD internal clock as the master network clock, be sure to configure any network devices directly connected to the Cisco IAD T1-WAN, T1-PBX, and serial ports to obtain their clocking from the Cisco IAD.

To configure the Cisco IAD to use its internal 2 Mhz. clock as the clock source, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# network-clock-select 1 system

Configures the Cisco IAD to generate clock internally.

Step 2 

Router(config)# controller T1 0

If your Cisco IAD has a T1-WAN port, enters controller configuration mode for T1 0.

Step 3 

Router(config-controller)# clock source {internal | loop-timed | line}

If controller T1 0 is not a backup clock source, configures it to use internal (system) clock or loop timing.

If controller T1 0 is a backup clock source, configures it to use external (line) clock1 .

Step 4 

Router(config-controller)# exit

Exits controller configuration mode.

Step 5 

Router(config)# controller T1 1

If your Cisco IAD has a T1-PBX port, enters controller configuration mode for T1 1.

Step 6 

Router(config-controller)# {clock source {internal | loop-timed | line}

If controller T1 1 is not a backup clock source, configures it to use internal (system) clock or loop timing.

If controller T1 1 is a backup clock source, configures it to use external (line) clock1.

Step 7 

Router(config-controller)# exit

Exits controller configuration mode.

Step 8 

Router(config)# network-clock base-rate 56k

Sets the network clock base rate for the serial port.

Step 9 

Router(config)# interface serial 0

Enters interface configuration mode for the serial port.

Step 10 

Router(config-if)# clock rate network rate

Specifies a clock rate for the serial port. The rate must be a multiple (up to 32x) of the value set with the network-clock base-rate command—in other words, n x 56000, where n = 1 to 32.

Step 11 

Router(config-if)# exit

Exits interface configuration mode.

Step 12 

Router(config)# Ctrl-Z

Returns to privileged EXEC mode.

Step 13 

Router# show network-clocks

Displays the network clock configuration.

1 To function as a backup clock recovery source, a controller must be configured for external clock. It operates in loop-timed mode when not recovering clock. If a controller is specified as a backup clock source, you must configure it for external clock, but it automatically operates in loop-timed mode unless it is recovering clock due to loss of a higher-priority clock source.

Configuring a Hierarchy of Backup Clock Sources

You can define a hierarchy of backup clock sources. This tells the system where to look for clock if the primary clock source fails. If no backup clock sources are specified, the system switches to internal clock whenever an external clock source fails.

Configuring Backup Clock Sources

To configure a hierarchy of backup clock sources, complete the following steps beginning in global configuration mode:

 
Command
Purpose

Step 1 

Router(config)# network-clock-select 1-4 [serial 0 | system | bvm | controller]

Specifies a clock selection priority from 1 to 4 for each clock source: 1 for the primary clock source; 2, 3, or 4 for backup clock sources.

You do not have to reenter any clock-source priorities that you entered previously.

Step 2 

Router(config)# network-clock-switch [switch-delay-time | never] [restore-delay-time | never]

Configures the clock switching delay times.

The switch delay time option sets the delay time in seconds for switchover to the next-priority backup clock source.

The restore delay time option sets the delay time in seconds for reversion to a higher-priority clock source.

Step 3 

Router(config)# controller T1
{0 | 1}

If one of the T1 controllers is a primary or backup clock source, enters controller configuration mode for the controller.

Step 4 

Router(config-controller)# clock source line

Configures the controller to recover external clock.

Step 5 

Router(config-controller)# exit

Exits controller configuration mode.

Step 6 

If the other T1 controller is a primary or backup clock source, repeat Steps 3, 4, and 5.

Note To prevent clock source conflicts, be sure to configure controllers to clock source line after entering the network-clock-select commands.

Configures the other T1 controller to recover external clock.

Step 7 

Router(config)# interface serial 0

If serial port 0 is a primary or backup clock source, enters interface configuration mode for serial port 0.

Step 8 

Router(config-if)# clock rate line rate

Sets the clock recovery rate for the rate of the incoming clock. This value must be a multiple of 8000.

Verifying Your Configuration

You can perform the following tests at any time to verify the hardware or software configuration of a Cisco IAD:

•Display the hardware configuration with the show version command.

•Display T1 and SHDSL controllers with the show controllers command.

•Display the running configuration with the show running-config command

•Display the configuration stored in NVRAM using the show startup-config command.

The following example shows a typical running configuration with the initial configuration tasks completed: 

Router# show running-config

Building configuration...


Current configuration:

!

version 12.1

no service pad

service timestamps debug datetime

service timestamps log uptime

no service password-encryption

!

hostname iad001

!

enable secret 5 $1$xf8X$38Qbfc.8UfVFmsDLR61fh.

enable password cisco

!

network-clock base-rate 56k

ip subnet-zero

!

mgcp

mgcp call-agent 1.3.26.1 service-type mgcp version 0.1

no mgcp timer receive-rtcp

call rsvp-sync

!

voice service voatm 

 !

 session protocol aal2 

  cac master

!

!

!

!

!

voice-card 0

!

!

!

controller T1 0

 mode atm

 framing esf

 linecode b8zs

!

!

!

!

interface Ethernet0

 ip address 10.3.96.20 255.255.0.0

 no ip route-cache

 no ip mroute-cache

!

interface Serial0

 no ip address

 no ip route-cache

 no ip mroute-cache

 shutdown

!

interface ATM0

 no ip address

 ip mroute-cache

 no atm ilmi-keepalive

 pvc 35/37 

  vbr-rt 512 512 10

  vcci 2

  encapsulation aal2

 !

 pvc 40/41 

  vbr-rt 512 512 10

  vcci 4

  encapsulation aal2

 !

!

ip classless

ip route 192.168.254.254 255.255.255.255 1.3.0.1

no ip http server

!

!

map-class frame-relay 20

dialer-list 1 protocol ip permit

dialer-list 1 protocol ipx permit

!

voice-port 1/1

!

voice-port 1/2

 timeouts wait-release 3

 connection trunk 2105 

!

voice-port 1/3

!

voice-port 1/4

!

voice-port 1/5

 shutdown

!

voice-port 1/6

!

voice-port 1/7

!

voice-port 1/8

!

dial-peer cor custom

!

!

!

dial-peer voice 3101 pots

 application mgcpapp

 destination-pattern 3101

 port 1/1

!

dial-peer voice 3102 pots

 destination-pattern 3102

 port 1/2

!

dial-peer voice 3103 pots

 application mgcpapp

 destination-pattern 3103

 port 1/3

!

dial-peer voice 3104 pots

 destination-pattern 3104

 port 1/4

!

dial-peer voice 3105 pots

 destination-pattern 3105

 port 1/5

!

dial-peer voice 3106 pots

 shutdown

 destination-pattern 3106

 port 1/6

!

dial-peer voice 2000 voatm

 destination-pattern 2...

 session target ATM0 pvc 35/37

 codec g729ar8

!

dial-peer voice 2100 voip

 shutdown

 destination-pattern 2105

 session target ipv4:1.3.96.21

 codec g711ulaw

!

dial-peer voice 2103 voatm

 destination-pattern 2105

 called-number 3102

 session protocol aal2-trunk

 session target ATM0 pvc 40/41 100

 codec aal2-profile custom 110 g726r32

!

!

line con 0

 transport input none

line aux 0

line 2 3

line vty 0 4

 password cisco

 login

!

end

Saving Configuration Changes

Enter the copy running-config startup-config command to save your configuration changes to nonvolatile random-access memory (NVRAM), so that the configuration is not lost if there is a system reload or power outage. For example: 

Router# copy running-config startup-config

Building configuration...

It might take a minute or two to save the configuration to NVRAM. After the configuration has been saved, the following appears: 

[OK]

Router#