QinQ

[frater]

Although I have quite some experience with Layer-3 networking I haven't done much with VLANs in the past. Currently I'm setting up/revising a sort of "campus network" where a lot of NAT-routers were used.
I have successfully implemented pfsense 2.0 on a smal Atom PC with 2 NICs. On 1 NIC I defined VLANs for the WAN (10~15) and on the other I defined VLANs for LAN (100~140).

I thought of using QinQ to create a VoIP vlan (#3) and let it encapsulate in each VLAN that's used for the "Campus". VoIP devices typically have support for VoIP and these devices themselves can take that VLAN out of their local LAN.

On pfsense I want to configure a special interface with a DHCP-server and siproxd.

I would like to know if this on itself is a good idea and if this can be implemented easily.

I went to interfaces -> QinQ and set "First level tag" to 3 named it VoIP and its members are 100~140. I have somehow the feeling that it's the wrong way around, but maybe it's the right way.
I still don't have an interface for my VoIP (vlan3). Can I still create it on the host interface?

I already said I didn't have much experience with vlans and I'm still unable to find an answer for my basic question if VLAN-tagged traffic can travel over switches that do not have support for VLANs.

I will still have many questions left, but some answers on my questions and any useful tip is very much appreciated.

BTW
In siproxd I am able to use 1 WAN-interface. Not several….  Is this a limitation of siproxd or the webif?