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Delay sensitive VOIP

I am currently trouble shooting a frame-relay network with both data and VOIP traffic. One of my remote sites cannot make any VOIP calls across the frame. I am using Siemens HiPath 3550 w/ HG1500 cards which handle the voice g.723 conversion. I am using a Cisco 2611(12.2(5d) router at the remote site and a 3640 (12.2(5d)) at the host site. The routers are prioritizing the voice traffic. During trouble shooting we did a trace route between sites and noticed that between the ethernet and serial interfaces on the host router their was at least a 40-60ms delay . The delay from host to remote network is about 80-140ms. All of the other remotes have a network-to-network delay of less than 50ms. I am thinking the 80-140ms delay is causing problems with my voice calls. I am also wondering why it seems to take so much time between interfaces on my host router. Any thoughts? Below is some of the config info on the router to give a idea of what we are doing.

class-map match-any voice

match ip rtp 29100 31

match access-group 101



policy-map goodgabin

class voice

priority 100

class class-default


map-class frame-relay 768k_voice

no frame-relay adaptive-shaping

frame-relay cir 768000

frame-relay bc 7680

frame-relay be 0

frame-relay mincir 768000

service-policy output goodgabin

interface Serial0/0

no ip address

ip hello-interval eigrp 1 10

ip hold-time eigrp 1 15

encapsulation frame-relay IETF

no fair-queue

service-module t1 timeslots 1-24

frame-relay traffic-shaping

frame-relay lmi-type ansi


interface Serial0/0.1 point-to-point

description connected to Lattis

ip address

frame-relay class 768k_voice

frame-relay interface-dlci 104


Re: Delay sensitive VOIP

What routing are you doing? Are you using EIGRP or RIP? Try defining a static route from the internal network to the serial interface.


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