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Where is VLAN tagging taking place at? I do not see it as any part of the 802.11 frames, so I am presuming that it is happening in the portal/Ethernet port on the AP as it connects to a Ethernet switch.

Can someone help to clarify for me?

802.1Q vlan tag control information fields (tags) are carried in the 802.3 Ethernet frame as an additional 2 octet field preceding the 2 octet length/type field and following an additional 2 octet vlan protocol id field that takes the place of the original type field.

802.1Q vlan tags are carried in the 802.11 Wi-Fi frame as an additional 2 octet field following the 8 octet LLC/SNAP header found in the frame body.

In the context of 802.11, vlan tags for all but the native vlan are typically carried between the Ethernet switch and the 802.11 access point in Ethernet frames and stripped before the corresponding Wi-Fi frames are transmitted. Conversely tags for all but the native vlan are added by the access point before transmitting on the Ethernet.

If vlan tagging in end stations ever catches on we may at last see them in our wireless protocol analyzers. Perhaps you can see them now in a wireless distribution system between access points that both support vlan tagging. If you do please let me know.

I hope this helps. Thanks. /criss