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
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.