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New QoS markings????

I've heard rumours about Cisco changing the QoS markings that are done by default on the IP Phone. Is this true? Also if so, does this affect the use of AutoQos?

Many thanks in advance for your help.


Re: New QoS markings????

There is currently a migration taking place for control traffic. It has traditionally been marked as DSCP 26/PHB AF31. It is now recommended that control traffic be marked as DSCP 24/PHB CS3. Callmanager marks control traffic as CS3 as of CCM 4.0. Whether the phone marks control traffic as AF31 or CS3 depends on the phone model and software version you are using.

This certainly affects the use of AutoQoS. Depending on the version of IOS, you may find that traffic gets classified based on AF31, CS3, or both. The safest way to go is to classify based on both values, such as:

class-map match-all Control

match ip dscp cs3 af31

Hope this helps. If so, please rate the post.


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