Best technology for "repeating" a wireless signal

I've got a wireless ADSL broadband router at one side of a building, but its signal is very poor at the other side of the building. Therefore I need some sort of "repeater".

Let's say that the network I'm trying to get onto is as follows: SSID: MonkeyBrain Channel: 3 Network: 10.9.8.0/24 Gateway: 10.9.8.1

So far, I've heard of two kinds of technology for "boosting" the signal.

Technology 1: You have some sort of wireless device that gets an IP address on the MonkeyBrain network. This device then broadcasts its own network with a different SSID, different channel, different network. Let's stay that the new network is: SSID: GorillaBrain Channel: 8 Network: 192.168.1.0/24 Gateway: 192.168.1.254 When you send a packet to the internet from this new GorillaBrain network, it goes to the default gateway on GorillaBrain, which forwards it on to the MonkeyBrain gateway, which forwards it to the internet.

Technology 2: I'm not sure how this works, but you can actually have a device that just boosts the signal. You've got the same SSID, same channel, same network address. You can communicate in Layer 2 protocols with the all machines on MonkeyBrain because you trully are sitting on the MonkeyBrain network. I don't see how you don't have a problem with both devices (i.e. the broadband router and the repeater device) sending duplicate signals and taking in duplicate signals.

Which technology do you think is better? Which tends to provide a faster connection? Are there any other good ways of going about boosting a signal so that it's strong on the other side of a building? (The signal I'm trying to boost is coming from an ordinary broadband router that you'd get from an ISP, nothing fancy).

I was thinking of another way of doing it. Let's say that you have a device which does the following:

Technology 3: You want to be on the MonkeyBrain network. You have a wireless device that broadcasts an SSID such as GorillaBrain. It's on a different channel to MonkeyBrain (let's say it's on channel 12), but it has the same network address (10.9.8.0/24). When GorillaBrain receives a frame on channel 12, it forwards it on to MonkeyBrain on channel 3. In this fashion, you could have MonkeyBrain using WEP, and GorillaBrain using WPA, but essentially they're the same network. (e.g. if you went into the router statistics on MonkeyBrain then you'd be able to see all the hosts that are on GorillaBrain, also all the GorillaBrain hosts would get their IP address from the DHCP server running on MonkeyBrain).

Is there any device the accomplishes what I describe in "Technology

3"?

Can anyone please give advice as to what kind of "repeater" device I should get. My preference would be either Technology 3 or Technology

  1. I think Technology 1 would introduce unwarranted overhead and would add the complication of only being able to communicate via IP with machines on MonkeyBrain.

Can anyone suggest devices, and perhaps give me an overview of the technologies used? And don't be afraid to get technical, I've a decent knowledge of datacoms (and also of wave transmission and the like).

Thanks for listening! :)

Tom=E1s

Reply to
toe
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Why not move the wireless router to the CENTER of the building?

Reply to
D. Stussy

D. Stussy:

Phone line's at one side of the building. I don't want to run a long phone cable, nor do I want to run a long ethernet cable. Hence the want for a "repeater" of some sort.

Reply to
toe

Make and model of the wireless router?

Can you get any kind of signal through the building? If yes, then an improved antenna on your unspecified ADSL wireless router will probably help. However, if there are too many walls in the way, that's probably futile.

Alternatives to a repeater are:

  1. Power line networking:
  2. Phone line networking:
  3. networking over CATV coax cable:

Rewind for a second. 802.11 wireless is all done on Layer 2, the MAC layer. There is no involvement with Layer 3 services, that require IP addresses. The only IP address that really needs to be involved is the management IP of the device.

Boosting is not a good technical term. I suggest amplification, repeating, repeating, regenerating, or something similar.

That's a back to back bridge/repeater. It's built from two different wireless access points (not routers), with the Ethernet ports cross connected. What one access point hears, is retransmitted by the other wireless access point.

Reminder. Repeaters don't know about IP addresses. However, there are devices that do. For example, a WDS repeater does know about IP addresses.

Yeah, something like that. Again, the way it gets "forwarded" has nothing to do with IP addresses. It's all done with MAC addresses.

The one exception is a WDS bridge/repeater, which allows a wireless access point to simultaneously act as a wireless client bridge, access point, and repeater.

Those are mostly tower mounted bi-directional amplifiers. It goes between your unspecified model wireless router and the antenna. I don't think your application would be a good fit for one of these.

Yep. Same everything because the amplifier doesn't change any of the data. It just makes the signal stronger.

Yeah, I guess, whatever that means.

You *DO* have a problem. However, it's not what you're thinking.

802.11 wireless is half-duplex. You can only send and receive, one at a time. To prevent collisions, where two transmitters xmit simultaneously, there is an algorithm and timer included to prevent this. In a give airspace (within range of your system) only one transmitter can belch data at a time.

When you use a store and forward repeater to retransmit (repeat) your data, you have two packets going through the air, one at a time, in order to deliver one packet of data. Since you can only transmit and receive one at a time, this cuts the maximum thruput in half. Actually, it's usually much worse than half because the timing and synchronization are rarely perfect.

If you decide that a store and forward repeater is the answer, you should try this simple experiment. Drag your laptop, unspecified wireless router, and repeater into a closed room and set it up to move data. Use another computer as a server to simulate the internet. You'll find that with the repeater functioning, performance will suck, and downloads will be erratic. Remove the repeater, and things will work smoothly.

What's happening is by creating an artificially small airspace, all the 3 transmitters in the room are clobbering and colliding with each other.

In order of personal prejudice:

- CAT5 wire or fiber to the other side of the building is best.

- Power line, phone line, and coax cable networking is tolerable.

- A directional antenna just might work but tends to marginal.

- A WDS bridge works fairly well, but is messy to configure and supported on a limited number of access points and wireless routers.

- A simple store and forward repeater sucks but can be made to work.

- The absolute worst is a tower mounted power applier.

Fiber optic cable and transceivers.

See aforementioned list of alternatives.

Is "Ordinary" a brand name or are you embarrassed by your selection of hardware?

Won't work. Wireless is bridging and works with MAC addresses. If you duplicate a LAN IP block at both ends of a wireless link, it's going to act exactly as if you plugged the duplicate IP's into the other network. Bad idea.

That reminds me. Many WDS bridges will only do WEP, not WPA. This allegedly a side effect of the WPA key exchange mechanism. I'm not convinced that this is true and prefer to think of it as a bug. There are some products and alternative firmware that support WPA encryption on WDS, so I know it can be done. Chose your hardware wisely or you may get stuck with insecure WEP.

If you insist on using two RF channels, only a back to back pair of wireless bridges will do that. If you can do it on one channel, it's called a store and forward repeater.

Yes. Don't get a repeater. Run the CAT5 or piggyback on the house wiring.

You're going to have store and forward overhead no matter what technology you select.

Start here:

There's quite a bit on all manner of 802.11 technology. The reviews are especially good reading. For example, the WRE54G "range expander" review is quite informative. (8 pages)

There are really only three technologies.

  1. MAC layer repeating with store and forward by SSID (only repeats packets with a specified SSID on a single channel)
  2. IP layer store and forward on top of MAC layer client as a WDS bridge/repeater.
  3. Back to back wireless client bridges.

I'm not afraid of being technical. However, there's no need here. Methinks repeaters (and some mesh networks) simply suck and should be avoided. Note that mesh networks are just a collection of repeaters and suffer from them collision problems. Some vendors have dual radio mesh boxes designed to avoid the half-duplex collision problems.

Reply to
Jeff Liebermann

Don't want to - or can't?

Reply to
D. Stussy

Run the wire. It'll be much more reliable, faster and quite likely cheaper when you factor in the costs of the wifi hassle.

Reply to
Bill Kearney

I've got a wireless ADSL broadband router at one side of a building, but its signal is very poor at the other side of the building. Therefore I need some sort of "repeater".

We used these types of "AC wire" solutions to get an Ethernet connection out to a loading dock area. From there, we installed a hub and WiFi AP for the dock area...

You could use the "AC wire" solution to get an Ethernet connection to the other side, and then just install another WAP over there. OR - use the "AC wire" solution to go between the ADSL modem and the actual router/AP which then could be moved to a central location.

Reply to
P.Schuman

Your problem sounds simpler than the solutions you propose. Here's a few things to try:

1) Put a reflector on the antenna where it is to reach further 2) Reconsider running an ethernet cable to the center of the house if it's relatively easy. This is the obvious starting point: placing the wireless router to optimize coverage.

If it's still not quite enough, then a 5-7 dbi omni antenna may get you over the hump. They are cheap.

3) use powerline networking to: a: get the router centered in the house or b: to get an ethernet signal on the other end. From there you can connect directly or hang an AP on it

All of these solutions are easier and more reliable than the repeater route.

Steve

Reply to
seaweedsteve

Hi, please forgive me for digging up an old thread and for any other breaches of netiquette that I may commit, I'm new to this forum.

I have been trying to figure out how to set up an old-school wireless repeater using two wireless devices. (D-Link DI-624 & WRT54G w/DD-WRT) I know that I can just use my DD-WRT device to repeat the signal but I don't want to cut the throughput in half for the originating wireless broadcaster.

The situation: I am receiving a wireless signal outside my home from a neighbor. I have permission to use the signal but not to access or alter any settings on the neighbor's router. A faint signal reaches a couple rooms of my house but not all of them. I would like to: a) set up the Linksys/DD-WRT device with a cantenna to receive the signal from the source (this way I can also adjust the xmit power if needed) b) Provide that captured signal from the Linksys device to the DI-624 via ethernet cable c) Use the D-link to broadcast a wireless network within my home (on a different channel)

I know that this can be done. I know that it is what is referred to as 'Technology 1' in the thread above. I just don't know all the settings to use to make it happen.

When I was first researching this I could find several sites to help walk me through the process. Now that I have the hardware in place and I'm ready to begin, I can't find any.

If anyone can tell me what I need to know or direct me to a site that has the needed info, I would greatly appreciate it.

Reply to
lancer

What you need to do is break it into two parts: Client bridge and AP.

First you want a tutorial on setting up a client bridge in DD-WRT

Try:

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Or here:
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wiki page link is over-complicated, but is good to review if you have problems. For starters, I suggest you just use the pictorial diagram and ignore the written instructions. direct link to pictorial:
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Then setup your D-Link as an AP using it's interface instructions with some guidance from any AP setup tutorial. Here's one for DD-WRT:

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Basically, give it a unique IP address within your subnet and connect from the DD_WRT router's LAN port to the D-Link's LAN port. Typically. You will have to sort out DHCP (which device is going to give out addresses) and turn off the firewall, but that's it.

Oh, and set up your local security.

Note: You may want to keep your house on a different subnet from your neighbor's, so you may want to go ahead and use DHCP on your AP instead of letting the main router assign it. If your main router is on 192.168.1.x subnet, then maybe setup your AP to 192.168.2.xxx subnet and hand out addresses from there. Setup your gateways to forward it to the next device.

Maybe somebody else can chime in on the DHCP detail, but do study the AP setup and then see where you have questions.

Steve

Reply to
seaweedsl

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I don't think you will get a reply to this post Steve. If you look on the speedguide.net forums there have been no posts shown that have originated from alt.internet.wireless since 1st Jan 2009, the 2009 posts originated from speedguide.net.

Reply to
LR

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