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Cisco VoIP Implementations

  • Sample Chapter is provided courtesy of Cisco Press.
  • Date: Jan 1, 2008.

Basic Manual CME Setup Using the CLI

Router(config)# telephony-service

Enters telephony-service configuration mode.

Router(config-telephony-service)# max-ephones 24

Sets the maximum number of supported IP phones.

Router(config-telephony-service)# max-dn 48

Sets the maximum number of extensions.

NOTE: The maximum number of phones and extensions is platform and IOS version dependent.

Router(config-telephony-service)# load 79xx P0xxxxxxxxxx

Identifies the Cisco IP phone firmware file to be used by specific Cisco IP phones when they register.

Router(config-telephony-service)# ip source-address

Identifies the IP address and port number for IP phone registration.

NOTE: The default port is 2000.

Router(config-telephony-service)# create cnf-files

Builds the XML configuration files required for Cisco CME phones.

Router(config-telephony-service)# reset sequence-all

Resets all phones one at a time.

Router(config-telephony-service)# exit

Returns to global configuration mode.

Enabling Calls in the CME VoIP Network


Enables privileged EXEC mode. Enter your password if prompted.

Router# configure terminal

Enters global configuration mode.

Router(config)# voice service voip

Enters voice service configuration mode and specifies Voice over IP (VoIP) encapsulation.

Router(config-voi-srv)# allow-connections h323 to h323

Enables calls between specific types of endpoints in a VoIP network.

Router(config-voi-srv)# allow-connections h323 to SIP

Enables calls between specific types of endpoints in a VoIP network.

Router(config-voi-srv)# allow-connections SIP to SIP

Enables calls between specific types of endpoints in a VoIP network.

NOTE: A separate allow-connections command is required for each type of endpoint to be supported.

Router(config-voi-srv)# sip

Enters SIP configuration mode.

NOTE: Required if you are connecting IP phones running SIP directly in Cisco CME 3.4 and later.

Router(config-voi-sip)# registrar server expires max 600 min 60

Enables SIP registrar functionality in Cisco Unified CME with lowest values.

NOTE: Cisco Unified CME does not maintain a persistent database of registration entries across CME router reloads. SIP phones will have to register again.

NOTE: Cisco recommends setting the timers to their minimum values.

Configuring DHCP for the VoIP Phones

Router(config)# ip dhcp pool VoIP-POOL

Creates a name for the DHCP server address pool and enters DHCP pool configuration mode.

Router(config-dhcp)# network

Specifies the IP address of the DHCP address pool to be configured.

Router(config-dhcp)# option 150 ip

Specifies the TFTP server address from which the Cisco Unified IP phone downloads the image configuration file.

NOTE: This is your Cisco Unified CME router's address. It is recommended to choose a loopback address.

Router(config-dhcp)# default-router

Specifies the gateway address for IP phone.

Router(config-dhcp)# end

Returns to privileged EXEC mode.

Router(config)# ip dhcp excluded-address

Specifies any addresses not to be dynamically allocated.

Defining a DHCP Relay

Router(config)# interface fastethernet 0/0

Enters interface configuration mode for the specified interface.

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

Specifies the IP address for any TFTP and/or DNS servers.

NOTE: A separate ip helper-address command is required for each server if the servers are on different hosts. You configure multiple TFTP server targets by using the ip helper-address commands for multiple servers.

Router(config-if)# end

Returns CLI to the privileged exec prompt.

Enabling Network Time Protocol

Router# configure terminal

Enters global configuration mode.

Router(config)# clock timezone CST -6

Sets the time zone to Central Standard Time (CST), which is 6 hours behind UTC.

Router(config)# clock summer-time CST recurring 2 Sun Mar 2:00 1 Sun Nov 2:00

Optionally specifies daylight savings time.

NOTE: If the clock summer-time zone recurring command is specified without parameters, the summer time rules default to United States rules.

Router(config)# ntp server ip-address

Synchronizes the software clock of the router with the specified Network Time Protocol (NTP) server.

Router(config)# ntp master

Enables the router's NTP server.

NOTE: It is recommended to have a single authoritative timer or server that all devices and services in the network query.

Creating Directory Numbers

Router(config)# ephone-dn 1

Configures a directory number.

Router(config-ephone-dn)# number 1001

Assigns a phone number of 1001.

Router(config-ephone-dn)# name Bob Smith

Assigns a name to the directory number.

Creating Phones

Router(config)# ephone 1

Enters the ephone configuration mode.

Router(config-ephone)# mac-address HHHH.HHHH.HHHH

Associates the MAC address with ephone 1.

NOTE: The address must be in the format HHHH.HHHH.HHHH.

Router(config-ephone)# type cipc

Configures the type of phone.

Router(config-ephone)# button 1:1

Assigns the first button on the phone to directory number 1.

NOTE: The first 1 indicates the first button. The colon indicates a normal ringer. The second 1 represents directory number 1.

NOTE: The Directory number ephone-dn 1, using phone number 1001, with the associated name "Bob Smith" is linked to ephone 1 with MAC address HHHH.HHHH.HHHH.

3. CME Auto Configuration Using the CLI | Next Section Previous Section

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