QoS for VoIP

Unanswered Question
Jul 31st, 2008
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Hi All,

I have two routers connected with PPP (256 kbps) leased line and going to implement QoS for voice traffic.

my config is belwo which i got from cisco.

class-map voip

match ip precedence 5


policy-map llq

class voip

priority 128

class class-default



interface serial 1/0

bandwidth 256

encapsulation PPP

no fair-queue

ppp multilink

multilink-group 1


interface multilink 1

ip address

bandwidth 256


ip rtp header-compression iphc-format

ip tcp header-compression iphc-format


ppp multilink

ppp multilink fragment-delay 10

ppp multilink interleave

multilink-group 1

service-policy output llq


My problem here is, after I configure this config, one of my router was hang.

I am suspect multilink ip address that i need to configure. It is should be same with my serial 0/1 IP or should be ? that I found in cisco document?


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Ayodeji Okanlawon Thu, 07/31/2008 - 23:03
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Your multilink IP address should be the ip address you intend to use not the one on cisco's document.

This address should be in the same network as the router's multilink address on the other end of the link...


yee.lay.yo Mon, 08/04/2008 - 20:17
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Thanks for the reply.

Same IP address of my serial or different IP with same subnet?

Marwan ALshawi Tue, 08/05/2008 - 00:54
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put it same to ur serial interface but on the mulilinke interface

u should be able to ping it


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