I'd like to hook up the sole 4k IPTV box provided by my ISP to the TV in the living room of a house of two-decade old construction, which means the closest RJ-45 wall jack is unfortunately on the opposite side of the living room, away from the coax outlet & co. for the TV stuff. Even that RJ-45 is of questionable availability, because the wall plate is actually covered and the actual wiring might not be in there at all (the construction plan marks this as one of the two "ADSL" outlets, but with X marks, unlike the only one readily usable in the study, which is marked with a check mark.)
For practical reasons, I don't want to run cables from the FTTH modem, or my only openwrt device (a wndr3800, with separate 5GHz and 2.4GHz radios) to the living room TV.
IPTV setup via Powerline devices are reportedly susceptible to interference from large electric appliances.
Apparently for the IPTV box to register on the ISP's dedicated IPTV network, it needs to be connected to a few select LAN ports on the FTTH modem tagged as VLAN 55. I have reconfigured the FTTH modem from router mode to bridge mode. So now my openwrt AP/router is the gateway, where I've configured VLAN 55 and assigned it to both CPU (eth0) and LAN2 (port 2).
An older revision of the IPTV box is rumored to have built-in Wifi (allegedly accessible via the companion remote control). However the local ISP technician vehemently denies this revision of the box has Wifi capability. So forget about setting the box as a regulard AP or WDS client to the openwrt router.
I don't have another openwrt-capable Wifi device. So I set up a spare non-openwrt Wifi router (cheapo 2.4GHz-only TP-link) next to the livingroom TV as AP (WDS) client to the wndr3800 running openwrt, with the IPTV box connected into one of TP-link's LAN ports. The WDS works great.
The only remaining issue seems to be the pesky VLAN-tagging. I've tried creating a new interface named iptv2wlan0, bridging wlan0 (there's also a wlan0.sta1 according to ifconfig, presumably for the WDS) and eth0.55. I'm not sure what Protocol this interface is supposed to have, so I chose "unmanaged". However, that caused all the clients hanging off wlan0 (in WDS mode) and I assume any wired hosts connected via the TP-link's LAN ports to lose connectivity.
Is there a workaround? Is it just a matter of picking the correct Protocol for the bridged interface (currently bridging eth0.55 and wlan0, but I had tried eth0 and wlan0, to the same debilitating effect)? Even if the VLAN tagging issue gets resolved, I wonder if the non-VLAN capable TP-link would be able to pass along the VLAN info to the hosts connected via its wired LAN ports such as the IPTV box. That's the whole point of the exercise.