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New Member

QoS: Setting CoS Value for Native VLAN (IEEE802.1p/Q)?

Suppose you have router with a 100Mbit-Ethernet-Interface. To set

a CoS value (outgoing) according to IEEE802.1p you'll have to set up a


The native vlan is non-tagged, but can also be sent as a member

of the (then virtual) vlan 0 (null).

That way you should be able to send the priority to the other side

without using a regular vlan ID.

How can I/Can I tell my router to do so?

BTW: If the other side is a switch configured as an access port, will

it receive and use the priority sent on (the virtual vlan) 0?



Re: QoS: Setting CoS Value for Native VLAN (IEEE802.1p/Q)?

I do not get your question clearly. Can you please rephrase your question with examples?

New Member

Re: QoS: Setting CoS Value for Native VLAN (IEEE802.1p/Q)?

I think what he is getting at is that he wants to mark the CoS bits in the layer 2 header, yet CoS (802.1p) can only be implemented in the tag for 802.1q and he does not want to do any trunking on the port. I think I hear him saying he wants to avoid trunking if possible and still mark CoS.

New Member

Re: QoS: Setting CoS Value for Native VLAN (IEEE802.1p/Q)?

If you have a router with a 100meg interface that has IOS cable of doing dot1q tagging you could setup a policy to mark certain traffic with a specific CoS based on a class you configure matching an access-list. Is this what you are looking for ??