Last few days I've been trying to setup a multi-SSID <-> multi-tagged-VLAN setup (all SSID:s/VLANs in "bridge" mode, with the AP having one IP in management VLAN [not seen on WLAN]).
After a lot of trial and error I found out that the integrated switch chip inside the AP (v1.1) does not easily support VLAN IDs above 15. It would be possible to run the switch chip in a "VLAN bypass"-mode, but this is not possible using the current version of the switch-adm tools (the switch is set into VLAN-mode on switch reset). Bypass mode would make the switch ignore (and pass-through) all VLAN-tags, and the 8021q code in the kernel would then do the tagging/processing (like it does now). Bypass mode would also mean that all ethernet ports would have the same VLAN config, namely: default VLAN (eth0.0) untagged, everything else tagged. Per-port settings would no longer be possible.
Being a lazy ass, I decided to renumber my existing VLANs so that all the WLAN-related networks would use <16 VLAN IDs.
There is another problem though. When doing an iwlist from a Linux computer, one will see all of the SSIDs, but all of them will have the same MAC (the AP WLAN MAC). Now, depending on sw/os, this either will be a problem, or might not be a problem. Using wireless-tools on Linux normally works fine with all "virtual" SSIDs.
However, built in Windows XP WLAN-stack doesn't like the same MAC on multiple SSIDs, neither do any of the Nokia cellphones (with WLAN) that we tested yesterday. It will be pretty random which SSID will be displayed, but very rarely all of the SSIDs are seen in the GUI at the same time. Seems like the software on the phones is bound to the "one MAC one SSID"-idea too much. Also Nokia Internet Tables have the same problem, which is somewhat ironic since they're running Linux (but again the problem is the GUI tools).
So, is there a way to force separate MACs for each SSID?
In any case, I decided to document the problems that I've run across so far, since there's not too much info on the straight-bridge-multi-SSID-multi-trunked-VLAN-case. Oh, I wasn't successful at getting WEP to work at all (all associations failed, tried different keylengths and using 's:foofoo'-style passphases, to no avail). Currently using psk+psk2, which works just fine.