3 House Wifi Network - Advice

[nikster]

Hi,

I am about to move into the mountains, and there's no internet. So I am going to set up a system for the neighbors and at the same time get my internet in my house.

The setup is like this:

House A sees House B, about 1.5km distance. House

House B sees House C, about 500m distance

House A does not see House C - there's hills and trees in the way.

A has DSL and both of the others are too far from the switching station to get DSL.

All three should end up with a WiFi connection.

I have 3 DLINK 2100AP access points that can operate in 5 modes:

- Access Point (AP)

- AP Repeater

- Bridge (WDS - no idea why DLINK calls this WDS)

- WDS + AP

- AP client

I also know a shop where I can get a 14dbi directional outdoors antenna, and an 8dbi omnidirectional outdoors antenna.

The best and most hassle-free solution would now be to

- House A has an Access Point with the 8dbi omni

- House B has an AP Repeater with 14dbi directional pointed at House A and an 8dbi omni

- House C has an AP Repeater with 8dbi omni

Unfortunately, these DLINK APs have only one antenna (detachable). So I can only connect either an omni OR a directional antenna to them. Or can I somehow connect two antennas by just splitting the cable?

If I can only attach one antenna at a time, I will have to put two APs on House B and have to set A to be a WDS + AP, B_1 as WDS connect B_2 with ethernet and have it act as ... AP? Repeater?

Any advice or opinions would be appreciated. I know this is kind of a hard network setup question...

[Crossy]

You can't just split the cable to have two antennae, at 2.5GHz it just won't work and a dual antenna AP also may not work (never tried one with two different antennae).

How about this:-

House A (with DSL) has 14dB pointed at B, access point running as AP

House B has 8dB omni with access point running as a repeater

house C has another 14dB** pointed at B, access point running as client

** You MAY be OK with another 8dB at C depending upon conditions

[Opus]

I would worry you would need an "Industrial Strength" antennae and secondly, you may get te router timing-out.

[Prasert]

I'm not really sure if your equipment supports point-to-multipoint bridging, but that would be the most efficient setup.

Place the omni antenna at B, the location which has line of sight with both other locations. Use directional antennas at A and C. You will have to use the same frequency (channel) on all bridges!

Use UTP cable to connect the computers. If you want those wireless, use a seperate accesspoint on a different (non-overlapping) channel. Using repeaters in a bridge setup is theoretically possible, but has a very poor behaviour in real life.

The use of 2 antennas on an accesspoint is simply for diversity when you use the tiny antennas. When using an external antenna (1 is enough!) make sure you use good coaxial cable (low-loss, not the cheap RG58 or, even worse, television coaxial cable), with proper connectors. External antennas usually require a N-male connector on the cable.

[nikster]

You can't just split the cable to have two antennae, at 2.5GHz it just won't work and a dual antenna AP also may not work (never tried one with two different antennae).

How about this:-

House A (with DSL) has 14dB pointed at B, access point running as AP

House B has 8dB omni with access point running as a repeater

house C has another 14dB** pointed at B, access point running as client

** You MAY be OK with another 8dB at C depending upon conditions

I like this plan.

I believe I would need a second AP in house A so house A also has WiFi - or does the directional antenna give off enough excess radiation to provide house A with WiFi? I don't know how "directional" these really are, but I do know they are not like a laser pointer

In any case, even if I need two access points in house A, I think yours is a better plan because router modes are simpler so it's more likely to work

And I think the one on C would also be a repeater, no? Or a bridge + AP...

From B - C is a very clear line of sight, I am pretty sure that will work with all omnis.

[nikster]

I'm not really sure if your equipment supports point-to-multipoint bridging, but that would be the most efficient setup.

Place the omni antenna at B, the location which has line of sight with both other locations. Use directional antennas at A and C. You will have to use the same frequency (channel) on all bridges!

Use UTP cable to connect the computers. If you want those wireless, use a seperate accesspoint on a different (non-overlapping) channel. Using repeaters in a bridge setup is theoretically possible, but has a very poor behaviour in real life.

The use of 2 antennas on an accesspoint is simply for diversity when you use the tiny antennas. When using an external antenna (1 is enough!) make sure you use good coaxial cable (low-loss, not the cheap RG58 or, even worse, television coaxial cable), with proper connectors. External antennas usually require a N-male connector on the cable.

Thanks for the tips. Yes all houses should have wireless access, and the APs support point-to-multipoint, I also had two of them set up in a bridge situation although over a much shorter distance. Repeater mode worked just fine in that configuration. Of course, it may not work when two repeaters are daisy-chained - need to try that first.

I figured WDS + AP mode was just for my situation though - Wireless Distribution System + access point....

DLink has this to say about WDS + AP mode:

WDS + AP Mode

This mode allows you to use your Access Point as a bridge and as an Access Point at the same time. That means that the unit will communicate with other WDS-enabled bridges and with wireless clients simultaneously.

I did notice that the cable to connect the external antenna comes in a separate box and is quite expensive...

[Tywais]

I did notice that the cable to connect the external antenna comes in a separate box and is quite expensive...

The cable does have to be a good low loss grade. We use RG213 for our microwave system (2.856GHz) and it is expensive but worth it to reduce attenuation of the signal.

[george]

Interesting article about Long distance Wi-Fi

[Prasert]

The article is indeed interesting, but the distances they reach is mainly due to the power. Here in Thailand the maximum emission (EIRP) is 20dBi.

Something to consider when using repeaters: since the radio has to receive a signal and then re-transmit it to the next point, the throughput is reduced by 50%. Using another repeater means another 50% reduction.

[nikster]

The article is indeed interesting, but the distances they reach is mainly due to the power. Here in Thailand the maximum emission (EIRP) is 20dBi.

Something to consider when using repeaters: since the radio has to receive a signal and then re-transmit it to the next point, the throughput is reduced by 50%. Using another repeater means another 50% reduction.

A friend tested a Belkin MiMo router - the router was set up as-is, no external antennas, and the USB receiving end placed in a small satellite dish. That worked easily over 4-5 km. Unfortunately they don't make repeaters/bridges for Mimo (or Pre-n wireless) yet.

[nikster]

Interesting article about Long distance Wi-Fi

Great article, thanks!

[Prasert]

A friend tested a Belkin MiMo router - the router was set up as-is, no external antennas, and the USB receiving end placed in a small satellite dish. That worked easily over 4-5 km. Unfortunately they don't make repeaters/bridges for Mimo (or Pre-n wireless) yet.

Basically, any parabolic dish can be used for WiFi. The feed can be a usb wifi stick, or you can build a feed yourself. I modified accesspoints with built-in antennas with an external connector, so I can use any external antenna on it.

When you browse the internet, you can find many drawings and instructions for building your own antenna. Satellite dishes are often used for directional links.

[Crushdepth]

I also know a shop where I can get a 14dbi directional outdoors antenna, and an 8dbi omnidirectional outdoors antenna.

Can you post the details of the shop? I'm keen to get hold of a directional antenna myself...but haven't seen anything in the various BKK IT malls. Maybe I'm looking in the wrong place...

[swain]

I also know a shop where I can get a 14dbi directional outdoors antenna, and an 8dbi omnidirectional outdoors antenna.

Can you post the details of the shop? I'm keen to get hold of a directional antenna myself...but haven't seen anything in the various BKK IT malls. Maybe I'm looking in the wrong place...

Finding any antennas other then the desk top basic 8db gain units is next to impossible up here in chiang mai. If anyone knows where you can get a roof mounted unit in Thailand I would be very interested. For me Omni directional is fine. In the USA you can find them at fry’s electronics or one of many other electronic stores. You can buy them online from the USA for $50 and in the stores for a bit more

Going back to the USA next week, what is the deal with bringing that back with me from the USA? Are there any restrictions?

[Deksan]

Sorry to polute the Opening post ... But i think this would apply as well to a question I have been wondering for a while...

I have read in france and in other countries ( I m from france...) that many individual had set up a public wireless lan over a town. The idea is to create a free wireless network, where you can do anything that is possible usually over a LAN. So I was wondering :

- Does anything like that exist in bangkok ? (maybe some ppl started to do it ?)

- If it doesnt exist, is it illegal in thailand ?

- Would some ppl be interested in such a thing ?

Here is an example of a network in australia

http://www.wafreenet.org/?page=network

A list of network in the world from wikipedia

http://en.wikipedia.org/wiki/List_of_wirel...works_by_region

Thanks for reading / replying.

Edited October 19, 2006 by Deksan

[Deksan]

Bumping

[monty]

For wireless (wifi) equipment:

http://www.bangkokwireless.net/blaithaishop/index.php

[meatgrowler]

A friend tested a Belkin MiMo router - the router was set up as-is, no external antennas, and the USB receiving end placed in a small satellite dish. That worked easily over 4-5 km. Unfortunately they don't make repeaters/bridges for Mimo (or Pre-n wireless) yet.

Basically, any parabolic dish can be used for WiFi. The feed can be a usb wifi stick, or you can build a feed yourself. I modified accesspoints with built-in antennas with an external connector, so I can use any external antenna on it.

When you browse the internet, you can find many drawings and instructions for building your own antenna. Satellite dishes are often used for directional links.

i think it wold be easier to buy some good cheese and go to an internet cafe in chaweng......and feed

[Tywais]

If you can't afford one here are links to building your own (antenna) on the cheap (tin can waveguides).

http://media.iet.hist.no/wlan/Avgrensa/can...tennahowto.html

http://www.extremetech.com/article2/0%2C16...641186%2C00.asp

http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=12599

http://www.dxzone.com/catalog/Antennas/WiFi/ (many different choices here)

[Crushdepth]

For wireless (wifi) equipment:

http://www.bangkokwireless.net/blaithaishop/index.php

Many thanks, those 24db grid antennas look great Anyone actually bought stuff from this shop before?

[nikster]

I also know a shop where I can get a 14dbi directional outdoors antenna, and an 8dbi omnidirectional outdoors antenna.

Can you post the details of the shop? I'm keen to get hold of a directional antenna myself...but haven't seen anything in the various BKK IT malls. Maybe I'm looking in the wrong place...

Finding any antennas other then the desk top basic 8db gain units is next to impossible up here in chiang mai. If anyone knows where you can get a roof mounted unit in Thailand I would be very interested. For me Omni directional is fine. In the USA you can find them at fry’s electronics or one of many other electronic stores. You can buy them online from the USA for $50 and in the stores for a bit more

Going back to the USA next week, what is the deal with bringing that back with me from the USA? Are there any restrictions?

The shop where they offered me both 9dbi omnis and 14dbi directional antennas is called AREANEX, and its located on the 3rd floor of Pantip Plaza Chiang Mai.

It's hard to find if you are not looking for it, there are maybe 2 or 3 external antennas on display and a poster detailing all the stuff that they can order, up to rather large directional antennas (the 14 was not the biggest one they had). They also have computer cases and keyboards, the usual stuff, so if you were just passing by and not looking at the windows closely you would think it's just another computer parts store.

They are friendly but don't speak any english. So be prepared to do some gesturing and draw pictures if you don't speak Thai.

I think with all those, buying the directional outdoors antenna is only for people who don't want to touch hardware as it's rather cheap to build them yourself. Like me. Any time I touch hardware, it breaks, so I would rather spend 2000 or 4000 baht and have something that works for sure.

Sorry don't know about BKK but I would think...

[nikster]

For wireless (wifi) equipment:

http://www.bangkokwireless.net/blaithaishop/index.php

tx for that... waaaahhh they have WiMax antennas!! *drool*

oh, crap, they have the category but not the actual equipment...

Edited October 21, 2006 by nikster

[monty]

Crush,

I bought some stuff from them before, a bit difficult because they don't have a lot in stock!

They do reply in English both by phone and e-mail.

I orderd an item, payed for it through banktransfer, and then they couldn't get it. They asked permission to ship something similar (which incidently was cheaper as well) to which I agreed. The dfference in price they transferred correctly back to my account!

They do have (or make themselves) a lot of hard to find stuff, like all the different antenna connectors, and make pigtails (short adaptercables) to order with high quality low loss cable...

For the antenna enthousiasts, another easy to make high gain antenna is a patch antenna.

It basically exists of a pcb with a special pattern etched on it, mounted on a flat metal reflector.

If you can find the exact sizes of the pattern, they would be very eay made by your local electronics enthousiast. Pretty good gain, and a reasonable wide beam (<20 degrees ) so not to hard to align...

[nikster]

Quick update:

I did a first test with 3 houses, distance A - B > 1km, B - C ca. 500m. The results were excellent.

Equipment used:

All Access Points (APs) are DLINK DWL2100AP. If I was to buy all new ones I would probably opt for the Linksys WRT line with dd-wrt, the free linux based OS for these - the interface looks much nicer. But I already had 2 DLinks, and they worked, so I bought 2 more for a total of 4. Setting them up can be pretty unintuitive but once they work they are pretty solid.

The only cables AREANEX sells are 2m or 8m shielded cables - those are very nice, but the 2m is already 900 Baht. So I got all 2m cables (in the belief that 8m would incur a high loss even for good cables)

House A: DSL router, AP in Access Point mode, 19dbi directional antenna.

House B: AP in repeater mode, 8 dbi omnidirectional antenna

House C: AP in repeater mode, no special antenna (stock antenna)

Even with some plants / trees in the way, I got a 70% connection from House B, and a 65% one from house C. There was absolutely zero delay in accessing the router's config page in house A from house C, even though it was going over 2 repeater stations.

We had to look for a good spot for the antenna, and we didn't mount it fixed, nor did we put it in a particularly good spot - wherever we had access to power, basically.

An encouraging first experiment. Luckily my neighbor from house B turned out to be an expert on ham radio, so he knows about antenna placement and these things.

Next step will be to move the DSL actually to house A - I wanted to know if the WiFI works first in order to manage my risk there. Now we know it works, we are having TOT move it, don't know how long that will take as they have to take the actual physical phone wire and extend it 1.5km and run it to the new location. There are not enough wires going around in my area...

Then we will improve the network strength. There are many options, but most likely we will install a second directional on house B with an AP in bridge mode, then put another AP next to it via ethernet and have that serve WiFi for everyone else - maybe even with another directional antenna, but I believe the omni is absolutely fine.

I will also use an omni in house C for improved connection to house B. Together that should yield and industrial-strength WiFi network that will work in fog and smog, the latter a problem when the farmers start burning stuff on the fields, we tend to get LA-like sunsets here at that time.

Most surprising to me was that the line of sight between A and B isn't very good or clear - there are some banana plants in the way. We just tried it where it would be most convenient maintenance-wise and it worked from there without much positioning, just hanging the omni from the roof, we got 70%. A proper directional antenna in the same spot should yield a strong connection.

[nikster]

Sorry to polute the Opening post ... But i think this would apply as well to a question I have been wondering for a while...

I have read in france and in other countries ( I m from france...) that many individual had set up a public wireless lan over a town. The idea is to create a free wireless network, where you can do anything that is possible usually over a LAN. So I was wondering :

- Does anything like that exist in bangkok ? (maybe some ppl started to do it ?)

- If it doesnt exist, is it illegal in thailand ?

Yeah, it's illegal. There are some rules on wireless, and from what I read, basically all radios are forbidden. Old laws, they might upgrade them for WiMax at some point. There seems to be some lobbying going on, but TIT things may take a while.

[Crushdepth]

I think (could be wrong) that broadcasting in the WIFI range is ok, but there are limits on transmission power of equipment.

[nikster]

CONCLUSION

My WiFi network is up and running. Some crazy delays, but TIT - it took TOT a long while to move my DSL to another house, but in the end it was fine.

The current setup is not ideal because as it turns out, there are some trees between house A and house B. So the connection there is far from perfect. However, it works right now, and I have been happily online for a while now. There are no discernible speed differences to a simple home WiFi.

House A: 19dbi outdoors directional antenna from TRENDnet

Hosue B: 8dbi omni outdoors antenna

House C: ditto

All WEP encypted.

The 19dbi connects to the 8 dbi, which in turn connects to the other 8 dbi. Router in House A is Access Point mode, House B and C run in repeater mode.

The DLink DWL-2100 APs work fine in repeater mode, but they are a bit finicky to set up and they now show a new phenomenon in that they lose the connection when I set them to scan mode. That's weird - perhaps I need to update the firmware.

Other than that, the repeater mode works fine though, even with WEP encryption enabled. I didn't want to do this initially because I heard it doesn't work, but it seems to be fine on the newer models.

If anyone wants to do this, I would recommend going with LinkSys WRT routers - the exacact model escapes me at the moment, but there is one that where you can load some open source firmware called "dd-wrt" and that looks *a lot* nicer than the DLink web interface.

I am going to put another 19dbi antenna on House B so that the connection there will survive fog and smoke - or cut down the trees ... Because that will be directional, there will need to be another AP and another directional for maximum gain everywhere.

As for making antennas myself, I might do with a friend who knows this stuff, but for the time being I would rather buy something that I know works than build something that might or might not work. Its easy... if you know what you are doing and you have the tools and materials handy. If you don't know what you are doing, don't have the tools, and don't have the materials... well not that easy

Important Note: Setting up such a network is completely impossible without Netstumbler. Netstumbler tells you the signal strength and more importantly how stable the signal is, e.g. if there are dropouts. I walked around with my laptop to find good locations for the antennas and without that it would have been impossible because the good spots are not where you would think they are.

So walking around with the laptop with NetStumbler running is vital. I would go around slowly, and when I got a good signal stop for a while to see if the signal would stick around for something like half a minute, e.g. no dropouts. All the locations I put the antennas, there were no complete dropouts though the signal would go up and down.

Edited December 13, 2006 by nikster