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Cisco QOS

Hello, I have been asked to set up QOS on our cisco 881 router for our new phone system, and I was wondering if someone would be able to help as I’m not 100% confident is setting QOS, I understand the basic concept but I am unsure how to set it all up correctly. Any help would be greatly appreciated

Router Bandwidth is 10MB, so I’m planning on giving 50% to the phone system, unless there is a better way?

And this is what I was told required QOS
SIP (signalling) - Class 3, AF31, DSCP: 0x1A, TOS: 0x68 RTP (media) - Expedited Forwarding, EF, DSCP: 0x2E, TOS: 0xB8

So this is my start on the QOS settings

ip access-list extended PhoneSystem
permit tcp any any range ?????

class-map match-any VoIP
match access-group name PhoneSystem

policy-map MyQoSPolicy
class VoIP
priority percent 50
set dscp ef

class class-default
fair-queue

interface FastEthernet4
bandwidith 10240
description WAN Interface to the Internet running at 10240
ip nbar protocol-discovery
service-policy output MyQoSPolicy

mat1458

You could change your class map a little:

class-map match-any VoIP
match protocol rtp audio
match protocol sip

That way NBAR identifies the protocols. It keeps track of the calls' source/destination ports.

How many parallel VoIP calls do you have across the Fast Ethernet 4? Do you really need 50%? Not that it is a problem but ist seems to be a lot since you use a Cisco 881.

I did not understand all your DSCP calculations, from the config I derive that you only want to protect voice and transport bearer traffic as well as signaling in the priority queue.

stephenHenderson123

ASKER

Thanks for the quick reply !!
We will probably max out at about 30 parallel VoIP calls, yes VoIP is the main traffic I want to protect, and everything else can be a free for all. Is 50% an overkill?

Updated Config below

class-map match-any VoIP
match protocol rtp audio
match protocol sip

policy-map MyQoSPolicy
class VoIP
priority percent 50
set dscp ef

class class-default
fair-queue

interface FastEthernet4
bandwidith 10240
description WAN Interface to the Internet running at 10240
ip nbar protocol-discovery
service-policy output MyQoSPolicy

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mat1458

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stephenHenderson123

ASKER

Thanks you that's perfect!!!
I will wait to hear back about conformation about the Codec, I believe its either g711 or g711.1

mat1458

You're very welcome.