Hi all,

I am planning to link two houses via WIFI using a yagi antenna on each side but I'm not too sure about the software setup...

Should I use WDS ? I would like to cover both houses with WIFI as well as have them linked to each other. If I don't use WDS I suppose I'll need to install 2 extra APs right ?

What wireless routers am I best buying ? Should I stick to linksys since OpenWRT started with Linksys hardware ?

Thanks,

John Gillespie

If I decide to go for a Linksys router with 2 antennas can I use 1 port for the YAGI and the 2nd one for local clients ?

So what is your actual setup? Do you need both routers to allow clients to connect wirelessly? Than WDS is good.

Be careful about Linksys routers, their modern versions don't support OpenWRT unless you go for a WRT54SLGS or a WRT54GL. Other companies have OpenWRT ready routers more reliably but I don't know the specifics (I just have a bunch of ones I got years ago or bought used).

I don't think you can divide the antennas like that. You may wish to just get two. Alternately you can use only one antenna.

Currently one of the houses is covered with a Linksys router (OpenWRT). I do know that one has to be carefull choosing the hardware they plan to run OpenWrt on.

The thing I was wondering about though was if OpenWRT is know to run on certain routers more reliably than on others. Currently I use a Asus WL500gP for my own home access but I get poor wan throughput (even when testing with a lan access behind the wan port) :-(
Upgrading from whiterussian to kamikaze improved things slightly but it is still an issue.

I don't want to run in to the same problem, I want to be sure that I get the best possible performance out of the hardware I will be choosing to run OpenWrt on this time.

Can someone confirm that I can't use the second antenna to provide WIFI access to clients whilst using the first antenna port with a YAGI antenna ?

Hi,

as far as i know most of the accesspoints only have one wifidevice and it switches between the two antennas to the one with the stronger signal, so the antennas aren´t active at the same time. So I guess its not a good idea to use one accesspoint with different antennas for both the local wifi and the link between the buildings, because it has to switch beween the two antennas all the time. I´m not sure if this setup would work at all, and if it works,  I don´t think this would work very well. so you should think about getting a dedicated acesspoint for the link at every location, or maybe an accesspoint with two wifidevices, but i think they are quite expensive.

ok thanks for the info. I'm starting to wonder if I'm not best going for 2 fonera APs for the WIFI bridge.

I intend to use this link for file transfers as well as "normal" internet access usage, is it worth going for a Super G AP ? would I need any special antennas ? What access point would I be best going for to acheive high transfer rates ?

your transferrate will highly depend on the distance of the link, the sensitivity of your wifidevices and the gain of your antennas.
using two foneras for the link can be a good idea, the fonera has a atheros-wifi which has a good sensitivity, it´s much better than most broadcomdevices, it is quite cheap, and I think it has many settings to optimize long-distance-links.
I use a fonera as wifi-client myself. it´s placed in the flat of a friend and connects to the accesspoint (WL-500gP) in my flat. Both use their standard omidirectional antennas, there are some walls in between, and the distance is about 20-30 meters but I get a stable 6 Mbit link. But with free line of sight, and directional antennas with higher gain, you will get higher rates.

If the distance is´t too far, I would try to connect with the standard omnidirectional antennas, if this works you don´t need dedicated accesspoints, or special antennas for the link.
If doesn´t work, than you can try to connect with one directional antenna to the local wifi of the other location, so you only need one dedicated accesspoint, and one directional antenna.

and if it´s too far, than you have to use two dedicated accesspoints with two highgain-directional antennas.

I don´t think that extensions like super g would make a big difference, but using 11a-devices could be a good idea, because the 5GHz-band is not as crowded as the 2,4 Ghz where the 11b and 11g-devices, cordless phone, and things like that are running, and you have more channels, so you can use another, if you have interference.
On a long distance link the stability is more important than the transfererate, I think you would be much happier with a stable 2 Mbit link, than with a 54 Mbit link that only works sometimes

Thanks for this info, I'm quite decided to go for 2 fonera APs now but I'm still not too sure about if I should use WDS or not. I read that there is a performance loss when using WDS. Since fonera APs are cheap I'm tempted to get more of them to avoid using WDS. What do you think ?

What would you say is the best way to link 2 wireless AP to get the maximum transfer rates ? (Ignore distance between the APs). I want a wireless bridge, no routing between the different LANS. I think this is called WET mode... am I right ?

(Last edited by johngillespie on 18 Aug 2007, 16:08)

If you go WET you'll "lose" one of the APs. One will be an AP that allows others to connect, and the WET router will ONLY allow a wired connection, and will connect to the internet (????) through the AP.

Here is a drawing of what I am trying to acheive :

I'm not bothered about having wifi access for clients in house2 if WDS reduces performance and that it is the only solution other than adding yet another access point.

You don't really need Fonera1. Just have Fonera2 connect to Linksys via STA bridging (aka WET).

Technically NO I don't need fonera1 but because of my linksys's position in House 1 I need fonera1 otherwise the link won't be available 24/24h and I can't move it.

the answers I've been given here have helped me a lot yet I still haven't been told if WDS damages performance or not. how badly ?

Thanks

Well it does yes, basically by half, but I think that would only count if you were connecting wirelessly using the PC3, which you are not. Basically when you have two devices connected (wirelessly) to one device the time it takes to go in and out of the router is much more delayed than if it were going from wired to wireless, or vice versa.

ok so if I set up the APs fonera1 and fonera2 in WDS mode I won't see any delay in performance as long as an extra wireless device doesn't connect to one of the APs ? I'm not sure I've understood the issue involved in having an extra client.

If you use the device as repeater (wireless uplink, und local accesspoint on one device) you always get only half bandwidth.

the best setup with the highest bandwidth with your number of devices could be to use fonera2 as ap, and fonera1 in sta-mode. so if you use pc3 you have the full bandwidth of the wireless link, and you can connect with wireless-clients to fonera2. so you can use full bandwidth from the wireless client to the fonera2 and to pc3. only the traffic of an wireless client connected to fonera2 which should go to house1 have to be sent twice.

but I think you have to route between house1 and house2 to achieve this. If you brigde the two locations, and want to create a local ap with the same device too,  you always have only half bandwidth.

Considering that the AP fonera2 will be connected to a YAGI antenna (outside the house) there is little chance any clients will be able to connect to it from within house2 so I might be best off using fonera1 as an AP.

(Last edited by johngillespie on 19 Aug 2007, 22:44)