Anyone from tp-link able to respond. Even if it is to confirm the obvious, that the Deco in AP mode won't pass tagged traffic without stripping the tags. Saves me cracking open Wireshark and a mirror port...

Thanks.

As a general rule direct transmission of VLAN tags is not supported by most WIfi devices - there is no space provided in the standard frame layout for the tag AFAIK.  I believe some devices designed specifically as bridges have proprietary schemes but these are not generally recognised by other clients. Instead many vendors let you map VLAN tags onto SSIDs - which is somewhat the WIFI equivalent. If a trunk is desired another device at the other end must reverse the mapping.  Slightly messy as you can’t have a trunk for any VLAN but must setup in advance the set of tags to be mapped.

I am not aware of the Deco having either of those capabilities, but mine is an M5.  Outside of IPTV and the WAN side of the connection there’s not much requirement for VLANs on home networks so you may be hard pressed to find any home grade kit that does what you are looking for here.

Appreciate the input.

Interestingly with the latest M9 firmware a Guest WLAN (using VLANs) was provided for both ethernet and AP backhaul. So these devices can operate with tagged traffic for sure.

My current workaround is to take out a port from my router, assign its own IP range and use a dedicated Deco in ethernet backhaul to advertise a WLAN that maps to the network range I need for my setup. It works but it's fugly.

I remain hopeful after the last update that the devices can deal with tagged traffic but it's currently not exposed to users.