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Cutting Through a Wi-Fi Traffic Jam?
eric3xxx asks: "A week or so after Christmas, I tried to connect to my home wireless network and while I could see my access point I could not connect. After scanning the network, it turned out that there were at least twenty new access points in my apartment building (and in the surrounding buildings). Most of them had names such as 'linksys' and were all set on their respective vendors default channel (apparently a lot of people received 802.11b/g WAPs as presents). I tried changing the channel on my access point, starting at 1 and continuing through all of the channels, and none of them worked (probably since the channels overlap). In any case, I have no clear solution to this problem. I suppose I could boost the signal, however, that also increases noise. Perhaps I could convince my neighbors to put together a shared wireless network. I may just switch to 802.11a since it isn't as widely used." Has anyone else had success in configuring their APs to work in an areas of heavy wireless traffic?
The answer is staring you in the face. You simply find one of your neighbor's Linksys routers that's wide open, and save yourself $40/month on your Comcast bill. Duh!
John
How about some Wi-Fi Proof Paint? Or just freeload on your neighbor's network...
Okay, here's the procedure: (1) Call your DSL or Cable provider and cancel your internet, (2) sell your wireless router on eBay, (3) choose an unsecured connection and go nuts. Simple, no? Plus it has the advantage that when the MPAA or RIAA come knocking, it won't be on your door...
Or you could install a Faraday cage in your apartment. Much more expensive, but much more cool IMO.
Every year during my review, I just pray the words "slashdot.org" aren't mentioned.
If your router supports it, grab an open source firmware, and step outside the normal 1-11 channels. Channels 12 - 14 are almost guaranteed to be empty.
I find that my neighbors are shouting near me when I want my child to shout the news to me . I cannot hear my child over the neighbor children and I have already tried having my child scream at very high and very low pitches (along with everything between).
Should I convince my neighbors to hire a single child to shout the street news for all of us?
Should I make my house soundproof?
Should I train my child to shout louder or in a different language?
Should I move?
This isn't a technical problem at all!
Having this problem here as well. My new Netgear 802.11g works just fine on channel 11 - but this is one of their new products which has the ability to do 108Mbps. The problem is that the 108Mbps feature is only available on channel 6 - the router will not let you select another channel if you have 108Mbps enabled - and I have *TWO* neighbors with WAPs on channel six.
.
At this point I'm seriously considering returning my Xmas present and just getting the next model up, which does 108Mbps over 802.11a 5.8GHz, thus bypassing 2.4Ghz entirely . .
--Ryv
The non-overlapping channels are 1, 6, & 11. Don't use anything else as this just overlaps with the other two default channels. You can also discourage your neighbors from using the 2.4GHz frequency by buying a 2.4GHz phone and leaving it off the hook for a while. Also, make sure you microwave lots of water. That'll piss em off real good.
It's called cat5. Look it up.
Back in Law School, there were a number of students in my class living in the same apartment complex. When one of my classmates got himself cable internet and a wireless router for him and his room-mate, we offered to "buy" access from him. (Most of us had newer laptops with WiFi cards) When the dust settled, each of 5 students paid about $30 for cable internet at home for the entire semester. It pays to get to know your neighbors.
Trying to use sarcasm in text-based forums does not work.
My ethernet cable laughs at your meaningless WiFi interferance!!! muhahahaha!
I'd probably opt to cooperate rather than isolate, specifically:
:-D
1) Contact the neighbors (door to door, flyers, etc) and inform them of the problem, offer to secure their WAP's and put them on a Wi-Fi co-op that would give the entire complex a single Wi-Fi connection
2) Contact an ISP that's willing (I know Speakeasy, Slashdot's sponsor is doing this) and get a big pipe from them (High power DSL or T-1)
3) Set up one WAP as the main station and configure everyone else as a repeater
Advantages:
1) Big fat Wi-Fi pipe
2) Wide range (entire complex and then some)
3) Everyone has tighter security if you know how to set up Wi-Fi properly
4) Joint budgets make this more affordable
Disadvantages:
1) Bandwidth hogs (though it can be mitigated)
2) Bickering neighbors or those who refuse for whatever reasons (good diplomacy skills here)
3) Large initial expense (those T-1's aren't cheap if you go that route, good equipment and setup charge investments involved)
So far it hasn't been a problem in my area, I personally appreciate being the one secure well guarded WAP with 3 other Default SSID's around me
Unfortunately if this isn't plausible for you, I fear you might be stuck going 802.11a or how about just plugging in the ol' cat 5/6 again?
...in bed
If the routers are using the default SSID of linksys, and they're also on the default channel, chances are WEP isn't enabled.
Just connect to one of these networks, open up your browser to 192.168.1.1 (password should be 'admin'), select the tab called 'Wireless,' and uncheck 'Enable Wireless Connections.'
Rinse and repeat.
For instance, on my network, there are a few iTunes databases feeding to the TiVo, the TiVo has to see the music to play it, all of which has to be on the same subnet. And that's just my roommate. I use several automated ssh scripts to play time shifted radio in various rooms (office, bedroom), have a NFS server with loads of video that I'd like to keep private... or the college kids in the neighborhood will suck my bandwidth like an Earnest movie.
In short, all is well and good... if *all* you want is bandwidth to one machine and never wish to reliably connect to another machine you own... and don't care about the privacy of your network.
--
Evan
"$30 for the One True Ring. $10 each additional ring!" -- JRR "Bob" Tolkien
I was thinking of something more evil. (eviler?) Just login, turn off their wireless all together, and change the default password. No more noise. Truthfully, I would just go with hacked firmware that allows the use of other channels.
as it is the phones. A friend of mine recently got one of those new fancy 2.6ghz cordless phones, and was calling me and complaining that his wireless kept going out. I just said "phone...". He then put 2 and 2 together and realized that every time his phone rang, he lost his signal.
Gotta love the FCC's bandplan. Stacking wifi and cordless phones onto the same spectrum.
I work for the Department of Redundancy Department.
FCC regulations for unlicensed spectrum mean that it's basically a free for all, you have to accept interference. You can't complain (technically anyways), and you can't intentionally screw with or overpower thier signal.
However, being a good neighboor can solve the problem with a bit of leg work.
My neighboorhood was the same way, AP's on different channels all over the place causing no ned of problems. I did a little direction finding, knocked on the doors and explained the problem. Ended up orginizing the entire block so that everyone was using non-overlaping channels and no-one was interfering with each other. Solved alot of thier problems as well in doing so.
Perhaps you might speak to your neighboors and see if you can bring a little orginization to the chaos. I'm betting your not the only one who's having problems, I'm sure your neighboors would love the help.
Where are we going, and why are we in this hand cart?
How does it change the router? What new features are added?
Even if you download it, it *still* doesn't tell you anything about the project.
feh. stuff.
1) Get an old microwave 2.4ghz microwave
2) Break off all the shielding*
3) Put aluminum foil 'reflectos' out the front of it and aim at the walls where nothing is in the way*
4) Unground the unit*
5) Put it on a timer to turn on when you are away from home.*
Eventually you'll either burn the place down or put out so much interferance your neighbors will take their WAPs back.
*please note doing this is idiotic and you'd be a real moron to do it....
The 802.11b/g spectrum is being loved to death in your building. If you've got twenty devices trying to share only three non overlapping channels (1,6,11) its a mess if anyone wants to go fast.
Setting the channel is the first step but you'll still get adjacent channel interference. Setting SSID *DOES* *NOT* *HELP*, nor does WEP/WPA. SSIDs define a group of nodes that are going to associate but the media layer (OSI layer 2) is *shared* for 802.11. That means two properly secured networks on different channels are still sharing the same stream of NAV (network allocation vectors) and they'll be stepping all over each other.
I could go on about this but I've got the flu and you've got internet access - get Matthew S. Gast's fine O'Reilly book on 802.11 and learn all the gory details for youself.
I am very easy to get along with, but I don't have time to waste being nice to people who are being stupid. -Theo
I never purchased a wireless bridge, because I was waiting for decent Linux support for 802.11a. A roommate's equipment negated the need after that.
Part of the reason why I was going to go "a" was because there weren't really any wardrivers checking out the network, and the other major part was that my cordless phone, microwave, and other equipment didn't use the frequency. I know that security through obscurity isn't a good idea as one's only line of defense, but using 802.11a, in addition to proper trusted/untrusted zone firewalling with WEP and software or protocol based encrypted tunnelling should have left me fairly secure for being over the airwaves.
I don't know the status of 802.11a in Linux right now, but if it's good then I'd recommend going to that. It may cost more, but it's faster, it's seperate from a, and relatively unused even by people with systems that would fully support it otherwise.
Do not look into laser with remaining eye.
You went about this wrong. You need to reconfigure all of THEIR APs to be on the same channel and clear on up for you. Or set yours on illegal channels.
I do security
ok, you have a high density of Access points, but you said it didn't work, not that it performed poorly.
If you do a search on the Internet you'll find several documents refering to a 4 channel configuration with minimal overlap (4%). The actual amount of interference caused by that layout is minimal due to the actual nature of the signal. (As opposed to the simplified version people have in there heads of why channels 1, 6 and 11 are the only ones to use).
Within an apartment you should be able to get a strong enough signal as long as all your immediate neighbors aren't on the same channel as you, and assuming your walls are not paper-thin.
If your trying to receive your signal across the street you will have issues.
On the other hand I only have 2 or 3 neighbors with access points and atleast one of them isn't clueless (WEP enabled) (even if it does suck)).
The "Turbo 108Mbps" products are only adding to the problem. The reason it is only available on chan. 6 is that it spreads itself across TWICE the bandwidth of "normal" 802.11g products (normal being IEEE/WiFi compliant hardware). There are limited channels defined for 802.11@2.4GHz, using these socalled "enhanced" products just further pollutes the spectrum and further exacerbates the problem of airspace congestion. Your neighbors (and ultimately yourself also) will suffer more than anyone benefits.
I liken it to laying down across a couple of seats on a crowded bus, or getting a huge SUV and parking it diagonal across two spaces at the supermarket - it's just rude.
At one time I used 802.11a, happily living on a 5GHz mountain all by myself.
Then my neighbor brought home a frequency-hopping 5GHz wireless phone.
And then paradise went away, and I found myself unable to connect to my "A" network any more.
Since the condo I live in has a very small yard with a lot of other suburban professionals nearby, I found, like the Topic Author, that I didn't have much of a choice in using "G", either.
Eventually I talked on of my father's employees (an engineer and a Ham enthusiast) into building a smallish 5GHz signal amplifier out of a few hundred dollars worth of his spare parts. The way he was talking I'm not even completely sure my neighbor's phone can even work any more, and I get reception on my (secure) "A" WLAN a full city block from my house.
-- I wanna decide who lives and who dies - Crow T. Robot, MST3K
Read the FCC notice for your WAP lately?
There's a reason folks that're "serious" about RF tech shy away from Part 15 gear.
I quote:
"This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.(emphasis mine)
Part 15 devices have no protection, no guarantee of function.
Seems quite the platform to base your IT world on, don't it.
Title 47 CFR:
http://www.fcc.gov/oet/info/rules/
Senior NCO in the fight against entropy. I've seen things, man. Things no one should have to see.....
This assumes your neighbors actually use the connection. (If they do not, should not most APs stay quite silent?)
Anyway....
1. Run airpwn
2. Watch your scared neighbors turn off APs in horror.
3. Wifi!!!
badness 10000
Locate your AP at the outside corner of your flat. Attach a pair of reflectors to the antennas, such that radiation will be concentrated only on your flat.
e x.html
By directing the power over 90 deg instead of 360, what do you think you have just done? Not only have you increased the transmit power, you've also vastly increased the receive gain.
Reflector templates can be found here:
http://www.freeantennas.com/projects/template/ind
I was in a situation where I needed broadband in an apartment w/out a connection, and used a DWL AP2000+ in client mode with one of these antennas (styrafoam, a kitchen knife, aluminum foil, and cellotape) to pull a symmetric 3.5mbps from an AP 600 meters down the street.
Make sure to put the reflectors on both antennas and point them both in the same direction. In almost all cases with such APs, only one antenna is transmit, while both receive.
I use these at home:
h p
http://www.netgear.com/products/details/XE102.p
Much better range and throughput than Wi-fi (in my experience) and no interference issues.
I had several neighbors with access points polluting my connection. I renamed my SSID to "Network Intruder Alert." I no longer see any other access points, and everything is clear now.
True story.
BTW - Microwaving water is *not* a good idea. Pockets of the liquid can become superheated, and leap into and scald your face without any prior warning.
Don't call me a cowboy, and don't tell me to slow down!
or M-x unmorse-region in emacs
Antennas get their gain by boosting the signal in one direction at the expense of signal in other directions. Your typical 8 dBi "omnidirectional" antenna sends very little of its signal up or down, while greatly increasing the signal it sends in the horizontal plane. Result: less interference for your upstairs & downstairs neighbors, and a much stronger signal on your level.
Or get a 14 dBi panel antenna (which focuses its signal in about a 60 degree arc IIRC) and stick it in a corner of your apartment.
The solution isn't adding more power or screwing with the neighbors' access points - it's
using external antennas to send the signal where you want it to go
figuring out which neighbor's AP is interfering with your signal the most and nicely asking him to choose another channel
E M P :)
$0.02 (CDN)
This should be the last resort because it is not a nice thing to do. So try all the other suggestions first.
A ham is allowed to use far more power on the 2.4Ghz band. Now there are limits to what you can do with this (which more or less exclude putting your AP on it). However as a licensed radio operators they must make sure their routers do not interfere with you when you are using your ham equipment!
A combination of cranking your power up, when they most want to use the net (shuts them off), and turning it way down othertimes until you cannot receive a signal because of their interference, and you can have the FCC shut them down.
Of course as a ham you need to check the laws closely. Make sure you are on the right side of everything.
I bought a DI-624 to use at home since I already connect my laptop to a DI-624 at work using a Belkin 802.11b card. Originally, I was using a Belkin router but I tested the DI-624 and found it far superior to the Belkin product in terms of range and speed.
To make a long story short, the DI-624 I bought for home was a different hardware revision than at work, with completely different firmware. Out of the box the DI-624 will not support 802.11b as it is configured to 802.11g turbo mode, so the Belkin card would not connect. I changed the wireless settings to disable the Turbo G mode and it still would not connect.
Finally, in frustration I brought the DI-624 from work (with two antennas as opposed to the newer version I had with one) along with a 802.11g D-Link PC card. Of all the combinations, Belkin 802.11b PC card, the "b" and "c" revisions of the DI-624, and a D-Link 802.11g PC card the Belkin wireless card and the "b" revision D-Link router had the best range and speed followed closely by the D-Link 802.11g card.
In the end, I simply swapped the "b" and "c" D-Link routers around and used the "b" version at home and the "c" version at work with the D-Link 802.11g card. It seems the 802.11 "b" and "g" standards leave a lot of room for interpretation, given that myself and others I have spoken to have had many problems getting products from one company to connect to another.
First of all, Have you considered that the issue could already be the walls themselves? You have not described your apartment, but many apartments have foil backed insulation or even chickenwire backed adobe or plaster in the walls.
Second, you're probably getting as much overlap from portable phones as you are from AP's in the building.
My advice differs from so many others. I say, centrally locate your AP in the apartment at the same plane as you'll generally be holding your laptop. That usually means about 30 inches for tabletop, about 20" if its actually on your lap keeping your genetals warm (and isn't that really why we all want Pentium 4 HT processors?).
If you're still not connecting on any channel, you probably have a config issue. Start with the basics. Reset the unit to factory config and change only the password. let it broadcast its SSID. Connect, then starting tightening it down. Don't sweat the hackers until you have something of value. Clearly, they don't need your bandwidth.
Also, learn about what blocks this frequency. In a nutshell, water. Anything with water. PEOPLE, for example, are excellent at blocking wifi. Your walls may have plaster that was water based. Chip off a piece and put it in the microwave for a few seconds. If it heats up, it will block wifi. The same goes for PVC plastics. Most won't, some will. A chip in the microwave for a few seconds will tell you.
I can't tell you how many times I see people in a coffee shop with wifi connection problems, when they've set the 900 ounce mochofrappafuckamacallit right next to their wifi card. DOH! If the signal is iffy, that's more than enough to kill it off.
Finally -- make sure you hit the basics. Get the latest (actually, sometimes teh second to latest) drives for teh wifi card and the AP, as well as any firmware upgrades. Don't laugh, sometimes it's really not plugged in.
You're in an apartment. Run some damn wires. Snake them under the carpet or hang the from the ceiling. Put lights on them and make them festive. Let your geek flag fly.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
Why bother with a T-1? Most folks don't upload and DSL/Cable download speeds are _higher_ than 1.4Mbps (at least in Canada). The extra cost for reliability and upstream bandwith are irrelevant for most home use.
This result can be derived from the van der waals state equation. There is a famous non-microwave case in which a teapot exploded in the kitchen injuring a housewife when her husband slammed the door.
The problem is that with an extremely smooth container (ceramic or glass perhaps) there are no nucleation sites (essencially rough spots) for the phase transition to occur, allowing the liquid to become superheated. The other way to force this to happen would be to disturb the fluid in some way, (such as slamming a door) which would start the process, the bubbles themselves would be sufficient for keeping the process going.
If pockets of water became superheated, then there would be no problem, the uneven heating would be enough of a distrubance to trigger the boiling process.
The solution is that you should never heat water (microwave or not) in a smooth container.
Even this might be ok if the water has high mineral content, but it's best to avoid the possiblity altogether.
on a slightly more on topic note however,
I'd rather not like to think of my microwave oven leaking enough RF to interfere with radio communications several apartments over.
Can you be Even More Awesome?!
If it's not working for you, how is it working for anyone?
"There is more worth loving than we have strength to love." - Brian Jay Stanley
I live in a town with pretty terrible (hard) water, i.e. it sure isn't pure. However, I can repeat an experiment on demand, which I have performed multiple times for various interested friends: microwave a coffee-cup full of water to just before it starts bubbling; remove it from the microwave; insert metal teaspoon into water (while wearing oven gloves); and BLAMMO, hot water everywhere. So, what's happening here? Methinks the mythbusters missed something.