WFQ vs policing

[steven.crutchley]

If I was running WFQ and wanted to give EF traffic 25% of the bandwidth. Would I do something like this?

policy-map POLICY
 class DSCP-EF
  priority level 1 
  police rate percent 25 
  ! 
 ! 
 class class-default
 ! 
 end-policy-map
!

The reason I ask is that, to me, guaranteeing bandwidth is about making sure that the scheduler removes packets from the various queues such that, 25% of what is taken is from this queue. Whereas policing is about altering (dropping/remarking) packets if they exceed a given data rate.

So is this the correct configuration to accomplish what I'm after or should I be using the bandwidth keyword?

[AshSe]

Hello @steven.crutchley 

You're absolutely correct in your understanding of the difference between guaranteeing bandwidth and policing.

In your configuration, you are using the priority command with police rate percent 25. This does not guarantee bandwidth in the way you are describing. Instead, it enforces a strict priority queue for the DSCP-EF class, but it also limits the traffic to 25% of the interface bandwidth using policing. If the traffic exceeds 25%, it will be dropped or remarked (depending on the policing action).

If your goal is to guarantee 25% of the bandwidth for EF traffic without policing (i.e., without dropping traffic that exceeds 25%), you should use the bandwidth keyword instead of priority and police.

Hope This Helps!!!

AshSe

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