Cisco Systems CISCO1751 quick start Tuning Parameters for Real-Time Voice Traffic

Configuring Voice-over-IP

Note For these commands to take effect, you have to cycle the port by using the shutdown and no shutdown commands.

Note Configure the PBX to pass all dual-tone multifrequency (DTMF) signals to the router.

Configure the East router similar to the West router. The East router connects to the PBX through an E&M VIC port 0/1. Enter the following commands to configure a POTS dial peer for all East telephones:

East(config)# dial-peer voice 211 pots

East(config-dial-peer)#destination-pattern 1919555....

East(config-dial-peer)# port 0/1

Enter the following commands to configure a VoIP dial peer for telephones on the West router:

East(config)# dial-peer	voice 221 voip
East(config-dial-peer)#	destination-pattern 1408555....
East(config-dial-peer)#	session target ipv4:192.168.19.27
East(config-dial-peer)#	exit
East(config)#

Enter the following commands to configure number expansion and to make it easy for East users to dial numbers on the West router:

West(config)# num-exp 5.... 1408555....

Finally, configure the E&M port:

East(config)# voice-port 0/1

East(config-voice-port)# signal immediate

East(config-voice-port)# operation 4-wire

East(config-voice-port)# type 2

Checking E&M Interface Configuration

If you configured the E&M interfaces correctly, you can place calls from a telephone served by one PBX to a telephone served by the other PBX (using just the extension, if you configured number expansion). If you have trouble placing calls, ping the remote router to make sure you have IP connectivity.

Note Refer to the section “Tuning Parameters for Real-Time Voice Traffic” if you need to improve the quality of voice connections.

Tuning Parameters for Real-Time Voice Traffic

Voice traffic is much more sensitive to timing variations than data traffic. For good voice performance, you need to configure your data network so that voice packets are not lost or delayed. To achieve the level of network performance needed for VoIP connections, use the following features to improve quality of service (QoS):

•IP precedence

•Resource Reservation Protocol (RSVP)

Cisco 1751 Voice-over-IP Quick Start Guide

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