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QoS on non QoS enabled L3 device

Hi,

I'm searching a confirmation about passing QoS on a L3 components without QoS enabled...Is it correct that the device will forward the packet as it is with the same ToS or DSCP received by others components which will mark packets?

Thanks for the feedback...

1 REPLY
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Re: QoS on non QoS enabled L3 device

Hi,

By default Cisco routers will pre-serve th ToS or DSCP values in packets as they pass through.

You dont need to configure each layer 3 hop to inspect and then re-write the markings on each packet. Thats the concept of a trusted QoS boundary.

Classify and mark close to access edge as possible, then trust the markings through out. i.e. use them to queue etc, but not have to classify and re-mark everywhere.

If you have service provider network in between though, you do need to be aware of what they may do to your markings.

Hope that helps,

Cheers,

Tim.

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