Min/Max Bandwidth in QoS Clarification

[Statix]

Hello. I'd like a little bit of clarification regarding how the minimum and maximum bandwidth parameters work.

I see that the preset Voip Service Class has a default minimum download bandwidth of 80 kbps. If I were to assign three devices to this Voip Service Class, does that mean that each of those three devices will have a minimum of 80 kbps allotted each? Or does it mean that all three devices will have a combined minimum of 80 kbps, altogether?

I am assuming the former, but some confirmation would be helpful.

Thanks.

[pbix]

All bandwidth allocations are per class. All traffic routed to the class must share the bandwidth.

In the case of the example VoIP class, 80kbps is sufficient for one phone conversation at a time.

[Statix]

Thanks for the clarification.

On a related note about QoS, I am trying to classify all Skype-to-Skype calls to the Voip class. Do you recommend that I resort to L7-protocol matching to inspect and classify all Skype packets? From some of the information I've read, matching by L7 protocol can be very CPU intensive and put a strain on the router.

My router is the Netgear WNDR3700 V2, which should have a pretty fast CPU, but I'm still concerned about the possibility of enabling QoS using L7 protocol identification bogging down my router's overall performance. My top priority is online gaming performance, and I don't want to enable settings that could negatively affect that, whether it be by additional overhead or latency caused by strain on the router.

Thanks again.

[pbix]

Read the QoS Wiki. My thoughts on L7 matching are documented there.