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QoS for voice data and voice signalling

What is the reccomended bandwidth allowance for voice signalling?

On our WAN routers we generally have  15% of the bandwidth allocated to anything marked with ef which is all the voice data.

But what is the best approach for signalling?

Should the config use the priority command or bandwidth command in the policy map (for signalling)?

And if we allocate 15% using the priority command to voice data, what percentage should signallying get?



Re: QoS for voice data and voice signalling

Have you seen the Enterprise QoS Solution Reference Network Design Guide that can be found here?

Here is a sample from the three class voice and data model.

As you can see the recommendation is to use priority for voice and bandwidth percent for signalling.

This document recommends 5% for signalling. This depends however on the type of phones you are using and what other business requirements you may have.

 class-map match-all Voice
  match ip dscp ef            ! IP Phones mark Voice to EF
 class-map match-any Call Signaling
  match ip dscp cs3           ! Future Call-Signaling marking
  match ip dscp af31          ! IP Phones mark Call-Signaling to AF31 
policy-map WAN-EDGE
  class Voice
   priority percent 33        ! Maximum recommended LLQ value
   compress header ip rtp     ! Optional: Enables Class-Based cRTP
  class Call Signaling
   bandwidth percent 5        ! BW guarantee for Call-Signaling
  class class-default
   fair-queue                 ! All other data gets fair-queuing

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