Hardware for vlan trunk over wifi

Good afternoon,
Greetings from France.

I have built a cisco lab in my garage with old routers and switches, in order to prepare a certification.
I can't install any ethernet cable between house and garage, but I can install a router nearby in the house.

With a WRT54Gv3 and a WRT54GL it works in WDS mode but only for the default vlan:

House/Cisco-C3560CX ------> House / WRT54G - - - - -> Garage /WRT54GL ----> Garage/Cisco lab

  •               eth                  WDS                   eth
    

Creating a trunk between the cisco and the copper ports of the wrt54g works flawlessly
The problem is that I need a trunk for my vlans.
It seems there is no way to tag vlans to the wifi interface.

So do anybody have some magic to have this working with these oldies, or do you have some more recent inexpensive models to recommend me?

  • Inexpensive
  • Possibility to create a trunk over wifi.
  • Strong wifi
  • Eth ports: Gigabit is not mandatory.

The most common brands available in the second hand market in France are, I think, Tplink, linksys and netgear.

Thnaks for reading me and for your advices. :slight_smile:

None of those devices (4/16) has been supported by OpenWrt in well over a decade.

It seems you stopped reading when you saw WRT54G. :smiley:

Is that even an existing technology to run vlan trough wifi? You can connect a wifi to a vlan, but as far as i know you can’t run the actual vlan in the wifi signal.

Please define “strong”?

Most probably do just that for a reason…

I agree with the sentiment of @slh - you're not going to be able to do any of this stuff with those old devices.

As @flygarn12 points out, VLANs are not really trunked over wifi in any standard way. There is actually a way to pipe multiple VLANs over wifi, but it is fairly complex and involves using GRE to do it. I've never attempted it myself. The wifi in this case becomes a point-to-point link and is not suitable for standard wifi client connections -- it is more like a wireless wire rather than typical wifi. The WRG54G will almost certainly not support this.

What you really want are dedicated PTP radios -- something like the Ubiquiti AirMax NanoStation devices, or a similar type of radio link from other manufacturers.

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Two UBNT AirMAX devices with stock AirOS firmware can be configured as a bridge that transports VLAN tagged packets transparently. This firmware uses a proprietary wifi driver and the signals emitted are not interoperable with standard wifi.

Doing this with OpenWrt / Linux is complicated since it expects to separate VLANs at each interface point. You will need to create a discrete network for each VLAN.

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+1 to @mk24. I was indeed referring to the idea of using the AirOS firmware and not attempting to run OpenWrt on those radios.

I used to be active on the Ubiquiti forums, and there are some examples of people who have used GRE to tunnel VLANs through a single 'standard' wifi link. I never tried it on that (or any) platform, but I do know that the link was approximating the idea of an AirOS connection and was no longer appropriate for normal client connections.

I did just find this thread for doing it on OpenWrt, although I don't think that it actually sends the tunnel over a radio. It would be an interesting exercise to get this type of thing implemented and documented, but it is not really a recommended path since it is a bit of a hack and requires quite a lot of advanced networking knowledge.

https://forum.openwrt.org/t/howto-l2-trunk-over-wifi-with-gretap/75689

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Ah... cool. I clearly didn't spend enough time searching.

You can probably do something similar with OpenVPN since it also can run vlans inside the encrypted tunnel over the internet if you use tap instead of tun.

Yes any tunneling protocol will do but vpn tunnels usually use encryption by default which will use cpu resources. Then again, since its wireless, encryption might not be a bad idea.

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Is anything other than wpa2 or greater even a question today?

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Thanks a lot.
I've ordered a pair of second hand ubiquiti nano station M5. Let's see when I receive them.

The pair of Ubiquiti M5 does the trick. My vlans do arrive tagged.

Thanks a lot.

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