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Community Member

Deploying VoIP and QoS

Hi, I hope you can help, the attached diagram shows overall what my network consist of, I understand cisco phones mark packets via DSCP marking, where else in the network do I need to apply QoS for this marking and also RTP? (L3 or L2 interfaces, both?) I have 4500 access switches connected via L3 links to 6500's which connect to the WAN via a L3 300 MB sonet ring and connect to another site with the same configuration, also, what would be a standard class map configuration or QoS policy that I would need to apply on these devices to prioritize VoIP, thanks again.

Cisco Employee

Re: Deploying VoIP and QoS


You will need to apply QoS on LAN and WAN. If the phone marks the packets, all the devices on the network i.e. routers and switches (L2 and L3) need to know how to treat the voice packets, if not QoS will not be implemented correclty and it'll be poor.

You can refer to the CUCM SRND Network Infrastructure chapter, it provides LAN and WAN QoS explanations.

Regards, Tere. If you find this post helpful, please rate! :)
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