Cisco Systems 1760 10

10 Use the CLI to Configure VoIP

The following sections explain how to set up basic VoIP configurations using the Cisco IOS command line interface (CLI).

Note VoIP requires one of the IP/Plus/Voice feature sets from IOS Release 12.2(2)XK, or later.

•Information for International Users

•Saving the Configuration

•Configuring the Fast Ethernet Interface

•Configuring a Dial Plan

•Configuring Voice Interface Cards

•Configuring Quality of Service

•IP Precedence

•Low Latency Queuing

•Multilink PPP with Link Fragmentation Interleave

•Real-Time Transport Protocol Header Compression

•Frame Relay Configuration for VoIP

International users must set the values of certain voice-port commands, such as cptone, that are specific to their country. Refer

to the Cisco 1751 Router Software Configuration Guide, available on Cisco.com, for details.

The rest of this guide explains how to configure your router for VoIP traffic.

You must save the new configuration to nonvolatile RAM (NVRAM) periodically during the configuration process and also

when you finish configuring the router.

Cisco IOS software uses two configuration files—startup-config and running-config. The startup-config file is a backup file that

has all the information you specified about the router interfaces. The startup-config file is used by the router on the next restart.

The running-config file has the current operating configuration with the changes you have just made. You can make any changes

to the running-config file; however, these changes will be lost when the router powers down. To make these changes permanent,

copy the running-config file to the startup-config file stored in NVRAM.

Follow these steps for each router to write the new configuration to NVRAM:

Step1 Exit configuration mode, and return to the enable prompt by pressing Ctrl-Z or entering the end global configuration

command.

Step2 To see the startup configuration stored in NVRAM, enter the following command:

Router# show startup-config

Step3 To see the operating configuration, including any changes you have just made, enter the following command:

Router# show running-config

Step4 To write your changes to NVRAM and make them permanent, enter the following command:

Router# copy running-config startup-config

Building configuration. . .

[OK]

Router#