OpenWrt Forum Archive

Topic: Wireless VLAN bridging trouble

The content of this topic has been archived on 23 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Two Linksys WRT-class routers, both running Kamikaze 7.09/Linux 2.4 (Broadcom):

  ------------
  | Wireless | DHCP
  | Client A | 172.16.0.101
  ------------                                  ------------
       |                                        |  Wired   | DHCP
       | Wireless AP (WPA+WPA2)           |-----| Client D | 172.16.0.100
       | 172.16.0.1 (bridged)             |     ------------
       |                                  |
---------------                           |     ------------
|   WRT54GS   |            Wired LAN      |     |  WRT54G  |
|    V2.0     |---------------------------------|   V3.1   |
|  Router A   | 172.16.0.1           172.16.0.2 | Router B |
| DHCP Server |                                 | No DHCP  |
---------------                                 ------------
       |                                             |
       | Wireless AP (WEP)                           | Wireless AP (WEP)
       | 172.16.1.1 (unbridged VLAN)                 | 172.16.1.2 (unbridged VLAN)
       |                                             |
  ------------                                  ------------
  | Wireless | DHCP                             | Wireless | DHCP
  | Client B | 172.16.1.100                     | Client C | 172.16.1.101
  ------------                                  ------------

The objective is to bridge the two wireless WEP APs on 172.16.1.0/24 in the same way that the WPA+WPA2 APs on 172.16.0.0/24 are.

Obviously, with the above configuration, the following is true:

- Wireless Client A can see Wireless Client B and Wired Client D but not Wireless Client C
- Wired Client D can see Wireless Client C and Wireless Client A but not Wireless Client B
- Router A and Router B cannot see one another on 172.16.1.0/24

What I am essentially trying to achieve is that anything on 172.16.0.0/24 (wired LAN + bridged wireless APs) can see anything on 172.16.1.0/24 (wireless unbridged VLAN) regardless of which router clients are connected to on the unbridged VLAN.  Preferably, all traffic on 172.16.1.0/24 between the routers should be routed over the wired connection on 172.16.0.0/24 if possible to minimize unnecessary wireless traffic.

I would really rather not use WDS for this, because:

- It will cut available wireless bandwidth at least in half, and will worsen with multiple clients on each router
- It is unclear to me whether WDS can be used on a wireless VLAN

I have read that parprouted may be a possible solution for this, passing ARP information between the two networks, but my attempts to configure it properly have not been successful (if it will indeed work at all).  It's also not clear to me how (or if) it would assist with my desire to route the wireless VLAN traffic over the wired connection.

I apologize if I have omitted any useful information, but any solutions/advice/thoughts from the community, particularly from anyone who has set up something similar on Kamikaze, would be very much appreciated.  Eliminating the wireless unbridged VLAN is unfortunately not an option, because I have devices on my network (security cameras, specifically) that speak WEP or nothing.

Rodney

Slightly ot but why bridged networks, why not routed networks ?

A routed network would suffice here, except that I suspect it will be unclear how the routes should be defined, given that the VLAN itself spans two routers.  Routes are not sensitive to nuances like ARPs and thus are geared more towards routing across different subnets/VLANs, no?

If you meant "why don't you use routing to allow the 172.16.1.0/24 wireless traffic to cross over the 172.16.0.0/24 wired network", that's precisely what I'm trying to achieve, though I'm less and less convinced it's possible.

Rodney

I had a re look at the picture, I thought it was a /16 the whole thing being flat.  But the first thing that caught my eye and what most people do (its actually the default setup) is to bridge the wireless and the lan together.

I have a rule to make all ethernet segment's == to ip networks [ there are alway exceptions].

This would help you in that you could watch the packets come to the router and move on {I have found bridging network much harder to diagnose}

If you want true wireless roaming switch to ipv6 mobile

The discussion might have continued from here.