Supercharging Your Linksys Wireless Access Point

kwishot writes "Xam over at www.wi2600.org has documented a relatively simple way to 'turn up the juice' on your Linksys WAP11 Wireless Access Point." Caveats: the outlined method requires a Windows box, recent firmware, and (some) bravery, but no going inside the box or special hardware.

Comments

Ignorant Legality Question

[Uttles]

Does the FCC have a problem with a person amplifying their wireless network without some sort of license? I'm totally ignorant on the legalities of this, but it seems like a really cool tip for free amplification!

Re:Ignorant Legality Question

[clark625]

Generally, the FCC only cares that you are within specified guidelines. I believe (and someone will correct me if I'm wrong here) that the 2.4GHz spectrum is limited in radiated power to 1mW. You can play all kinds of tricks with that by using highly directional antennae, and thus concentrating your 1mW power into one small cone. Or, you can spread the love around and try and radiate the 1mW spherically from a point source (hard to do).

Most of the 802.11b devices don't radiate nearly as much as 1mW. This keeps them well below the FCC specs, and thus out of harm's way. Cranking your radiated power up to the full 1mW is perfectly fine. The caveat, of course, is that now you're sharing your traffic with much more of the planet.

Cable is out.

[ImaLamer]

Now that cable services are starting to fall and AOL begins to take over the cable market wireless points will be a huge innovation.

But we are still waiting. Wireless is becoming the new thing, but communities need to respond. But buying these home [and business] wireless products hopefully this will fuel the boom.

Now that my cable service is dropping me when using any P2P service and even newgroups [ahem] I've considered buying a bigger cable/pipe which I can do what I'd like with. Something with more freedom and the abilty to share the access with home I want.

Now, my neighbors on both sides have internet access. One is my granparents whom use a $20 56K service and the others also use broadband [DSL].

I'm completely capable of running mail services, hell even a proxy server. I can do all these things with redhat or debain out of the box. No matter what their needs are I can set up the system.

Hopefully the wireless situation will become one where one could sell access to services. Whether they be a town, city or user group... let's hope wireless plays a big role in delivering a part of the 'last mile' solution.

Although if wireless becomes too much of a 'hobby' then large scale networks may not be seen. Hope we see a balance.

Re:Cable is out.

[Lumpy]

the problem is that your roof will look like a dish farm. 802.11 links require high gain antennas. the pringles can works but a primestar dish works 100times better. the best time to set up your links is mid summer. because 802.11 links will not shoot through trees with leaves. (nice how those water filled leaves absorb 90% of that RF energy you're beaming) getting to non-line of sight requires doubling the links to get around things... (A to B to C with B being a 486 with 2 wifi cards acting as a bridge) your house, if you are the hub will need a dish for every link.. (I gotta take pictures of my 60foot tower.. 3 primestar dishes on it, and 2 more going up this summer) now you can hub off of the other ends of the links, but only if you have control of the equipment at the other end and they dont care about 2-3 more dishes on their roof/tower (and I reccomend you demand towers at the other ends, makes it easier) get ready to have a new full time job if you do this. it will take most of your apare time, it will drain your pocket, and it will make you stop answering your phone. (calls from people when you have an outage, or it rains hard, or other problems... you just became an ISP and you'd be supries how people can bitch at you when their free internet goes down.

SNMP?

[omega9]

From what i can tell, this doesn't have to be a Windows only hack. The piece of software that Xam states is only built for Win32 seems to be nothing more then an SNMP manager. Now, the Win32 tool might make it a bit easier, but you can hardly call it "requires a Windows box".

The real trick

[LtBurrito]

The real trick is to get your neighbor to turn up his power so you don't have to buy your own...

Re:The real trick

[aka-ed]

Not much of a trick. Just give your next-door neighbor a WAP for Xmas and cancel your own broadband.

Wireless Phone interference

[joel8x]

Here's my question - I own a 2.4Ghz Seimens wireless phone and whenever I use that it cancels out my computer's wireless access! Does anyone know if this hack will affect this behavior (worse or better)? I would try it myself, but I use my iBook's Airport card for wireless access and can't run the program they use from my Mac, which would mean getting a PC wireless card to perform the hack.

Re:Wireless Phone interference

[jandrese]

Well, since your phone is probably some analog deal that just blasts out your voice, I'd say upping the power on the access point will just add a bit more noise to your conversation (and probably not help too much in keeping the signal strong when you pick up the phone, although it should help a little).

A better hack might be to change the channel on your access point to something on the other end of the spectrum since you phone may not be taking up the entire band (unless it's a DSS phone). Or you might try moving your phone's base station and access point to opposite ends of the house.

PS: Whoever modded this as a troll: what were you thinking?

Re:Wireless Phone interference

[Lumpy]

yes, buy a new phone. the cheap 2.4Gig phones will interfere with wifi equipment. that the problem with buying cheap junk. Seimens cordless high end lives heppily with wifi as does the top of the line panasonic ($350.00USD) phone. look for the ones that advertise spread spectrum and will operate with other phones in the same house. These see a signal on a channel (and actually use the channels instead of broadcasting on the entier band at once) and hop around it.

Re:Wireless Phone interference

[stripes]

2.4Ghz Seimens wireless phone and whenever I use that it cancels out my computer's wireless access

I have the same phone (three of them), and working 802.11 (with a Cisco 340, until it died, and then an Airport 'cause my office is close to the apple store...and it looks cool so my wife will let me put it in more "public" parts of hte house).

Try changing the channel you broadcast on, and try the "reduce interference" setting on your iBook. Also if you don't have really good signal before using the phones try moving things around a bit.

Does anyone know if this hack will affect this behavior (worse or better)?

Since it boosts the base station, and not your laptop's output, it may not help (you might be able to see it, but it may not see you), also the boost looks kinda small.

I would try it myself, but I use my iBook's Airport card for wireless access and can't run the program they use from my Mac, which would mean getting a PC wireless card to perform the hack.

I don't think you need to try the hack from a wireless machine, just something with IP access to your WAP base station. Plus while the instructions for the hack are for using a PC tool, it is all done using SNMP, so you can grab some of the SNMP tools for Mac OSX and translate the instructions yourself. It might not buy you much range, but it would be a learning experience...

Correction:

[clark625]

I goofed. The maximum radiated power is set at 1W. Not 1mW. Here's the FCC rules that apply, for those interested:

Part 15.247 covers intentional Radiators in the ISM bands that are the frequencies 902-928 MHz, 2400-2483.5 MHz, and 5725-5850 MHz. Besides covering the modulation schemes this part also covers the various power restrictions that the FCC has for devices like 802.11b. The critical section is 15.247(b)(1) through 15.247(b)(3)(i) quoted below:

"(b)The maximum peak output power of the intentional radiator shall not exceed the following:
(1) For frequency hopping systems operating in the 2400-2483.5 MHz or 5725-5850 MHz band and for all direct sequence systems: 1 watt.

(2) For frequency hopping systems operating in the 902-928 MHz band: 1 watt for systems employing at least 50 hopping channels; and, 0.25 watts for systems employing less than 50 hopping channels, but at least 25 hopping channels, as permitted under paragraph (a)(1)(i) of this section.

(3) Except as shown in paragraphs (b)(3) (i), (ii) and (iii) of this section, if transmitting antennas of directional gain greater than 6 dBi are used the peak output power from the intentional radiator shall be reduced below the stated values in paragraphs (b)(1) or (b)(2) of this section, as appropriate, by the amount in dB that the directional gain of the antenna exceeds 6 dBi.

(i) Systems operating in the 2400-2483.5 MHz band that are used exclusively for fixed, point-to-point operations may employ transmitting antennas with directional gain greater than 6 dBi provided the maximum peak output power of the intentional radiator is reduced by 1 dB for every 3 dB that the directional gain of the antenna exceeds 6 dBi."

Better range increase..

[Spackler]

The best way to increase the range of the linksys router is to not use a linksys card with it.

Switching from the linksys card to an Orinoco more than tripled my range! It also made me realize that the linksys router signal _was_ hitting the street (I thought it wasn't reaching my couch with the old card), and enlightened me to "War driving". If your having range problems in your house, it is more likely your card.

Good for overcoming line losses

[rcw-work]

At 2400mhz, 3-4db is equivalent to the loss in 45-60 feet of LMR-400 coax (or 12-16 ft of RG-58), according to this calculator.

For those that would like to put an 802.11b antenna on their roof without worrying about weatherproofing their access point, this may be just the thing.

This is an elementary SNMP set

[arivanov]

Browse the MIB supplied by Linksys on their web site and do the same with scotty. No real rocket science here. It is as elementary as it can get.

No need of the windows executable

It really makes me wonder...

[TheGreenLantern]

...whether hacks like this are just plants by the parent companies sometimes.

"So you tried to up the radio signal of your WAP11 by hacking it to boost the radio signal, and now it won't work? (Hey Bob, we got another one!) What, oh that was nothing sir. Sir, I'm sorry to say your warranty is void. But we do have a sale on the upgraded model right now..."

Re:It really makes me wonder...

[ZoneGray]

This is what Best Buy is for. The return clerks there think a "community string" is some sort of sex act. By the time you get around to explaining POSIX-compliant SNMP managers, they'll just issue the refund. Just make sure it's clean and all original packing is there.

Rather Clever, Really...

[The Paradox]

...but, as always, your mileage may vary. A watt of power is, while not on class with many ham radios, even, still quite a bit.

Essentially what I'm saying is, you turn up the power on this thing, you don't wanna wear it as a hat. Not that you wanted to do it before, but now you *really* don't want to.

Remember, Linksys is not turning down the power just to spite the geeks out there. I imagine it could easily be a safety issue. Either that, or they had to do it to meet the FCC interference standards. If that's the case, you could have problems with devices that operate in that section of spectrum - I seem to remember something about wireless phone (NOT cellular, *wireless*, as in a base unit, then a detachable handset) working there.

Also, just as a totally useless aside, looking at my handy-dandy (three or so years old) frequency chart I have here, I find it interesting that that portion of spectrum used to be for amateur radio operators. Co-located, perhaps, or did they just take it away from the amateurs altogether?

bad engineering practice

[lophophore]

Since the 802.11b communications link is two-way, increasing the transmit power of only one end (the access point) is not going to buy you a whole lot. To increase the range, you need to either increase the effective power on both ends, or, more simply, put the access point up higher.

A higher gain antenna on the access point would help with both transmit and receive, and this is another option, however, I think that this might be illegal in the US.

Also, it is useful to recall that microwave ovens operate on 2400 MHz because this is the most efficient frequency for heating water. One watt is enough to cause some RF heating and potentially be hazardous to you health. Don't look at the business end of that yagi!

Re:bad engineering practice

[synchrostart]

There are certainly risks associated with doing this hack. First thing is that the human body is most sensative to RF resonating between 30 and 3100 Mhz. Since this falls in that range, sitting next to that access point is probably not a good idea. And since sufficient studies have not been done to test the long term effects of RF on the human body, I wouldn't do it. Heck I keep my access point no less that 4 feet from me and I have the USB tranciever to keep it minimum 4 feet from me as well. And though 1 watt of power isn't a whole lot, when it is sitting next to you and is on all the time is probably not a good idea.

Re:Are there similar registers for the pcmcia card

[SpectreGadget]

For many of the pcmcia cards (probably not the cheap ones), a client utility is usually included that allow you to change the output levels. I actually turn mine down at work as I have an AP at my desk and I'd like to keep my hair. ;0) Really though, I'm only using it for testing so 1mW on both ends works just fine and reduces the chance of an attack (both internal and external, i work at a big company) since the range is reduced.

Other 802.11b improvements

[Arkham]

There are two worthwhile articles over at Macintouch about 802.11b (AirPort in the mac world). I thought they might be interesting to people looking to improve their wireless LAN performance or range.

Adding WaveLAN Extender - This article discusses adding various antennae to base stations to improve their range.

Extending TheAirPort's Range - This article discusses some more radical procedures, including some neat stuff with Directional Antennae which allow 802.11b to work as far away as a 57 Kilometers. They also discuss various antennae to add to laptops in order to improve their range.

Fun with Wap11

[bwags]

Funny, I just worked on boosting my power this weekend before this post. It works like a champ! This info came out earlier this fall but it is nice to see it all written up in such a nice manner. I have a whole bunch of printouts describing all this stuff and I somehow pieced it all togethter. I have a couple of notes of interest pertaining to this stuff:

First, I never did upgrade the firmware to 1.4g5 or 1.4g7, I am running 1.4H3. I guess I should upgrade, but that would require me to actually get the AP next to my PC for the USB connection. The upgrade seems to work OK without the latest rev as long as you can connect via snmp. I think I must have the 1.0 hardware since I got this thing Jan 2001.

Second, I think you can also turn off the SSID on your WAP using these utilities. I have not tried this but perhaps it could help if you are paranoid...

Finally, The main reason I worked on trying to fugure this out is because my wireless network was running very slow. I finally figured out the reason was the wpc11 linksys pcmcia card that I have. If you have one of these cards make sure to DISABLE the PowerSaveMode in your network configuration (in Windows). Your network will now run significantly faster (500K/sec instead of 50K/Sec in my case). Also when exploring in windows use mapped drives instead of unc names. This seems to also help.

Hope that helps, BRian

MIB hackery

[danish]

After installing the snmp utils (apt-get install snmp) and doing some minor surgery to the MIB so it would parse correctly, I think I've found the element to modify:

enterprises.atmel.atmelmib.atmelSys.TestModeSettin gsGRP.TestModeRadioConfiguration.0 = Hex: CA CA CA CA CA CA C9 C9 C9 C9 C9 C9 C9 C9

Although not in the same configuration as the article describes, this may be due to the fact that I've never upgraded the firmware on the access point I snmpwalk'd this from. Perhaps I should get busy on that....

Any of you people out there with an upgraded firmware, you should try snmpset under Linux or your UNIX of choice and see what kind of results you get... extra points for verifying the change with the Windows stuff in the article.

Numerically, snmptranslate says that the correct field is .1.3.6.1.4.1.410.1.1.8.8.0, assuming I'm using it right (I called it with the commandline snmptranslate -m +ATMEL-MIB -IR enterprises.atmel.atmelmib.atmelSys.TestModeSettin gsGRP.TestModeRadioConfiguration.0.)

Re:MIB hackery

[mmmbeer]

Nice job Danish. For noobs who just want to juice their WAP11 (192.168.100.250 is the IP addy of the Access Point):

apt-get install snmp
snmpset 192.168.100.250 public .1.3.6.1.4.1.410.1.1.8.8.0 x "80 80 80 80 80 80 80 80 80 80 80 80 80 80"

WARNING: I tried this hack...

[dstone]

...and my Pringles can burst into flames.