Hi,
I am studying CCNP BCMSN and I have a simple question to ask. I understand that COS is only possible in a 802.1q tagged ethernet frame. If I enable 802.1p on a workstation, does that mean this workstation have to be trunked to a switch inorder for the switch to receive 802.1p COS info? Thanks.
Hi
Let me put u like this....
We have IP precedence( TOS) at layer3. In the same way we have COS at layer2, as we dont have extra bits to specify he precedense at layer2 we introduce a tagging for layer2 packet ie 802.1q and ISL ( cisco propretiery).
when we enable the qos in switch by " mls qos " if we configure the port in Trust-mode( mls qos trust cos) and workstation sending the
802.1p tagged packets switch will consider the tagged packets for QOS no need to enable trunking.Have something to add? Share your thoughts — no account required.
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