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Escaping WiFi Interference In The Modern Dorm Room?
j.cherney writes "I recently moved my son up to a dorm at Michigan State University. We set up a wireless router (D-link) and everything worked well-until the rest of the dorm moved in. Now he is getting intermittent outages which I am quite sure is related to the large numbers of cordless phones on the 2.4ghz frequency. So my question to everyone is: Is there anything that I can do to make wireless work in this environment? Obviously I'm not willing to buy everyone in the dorm a new cordless phone! Is one brand more resistant to interference than another? Is there a filter than can be installed? Or is he S.O.L.?"
1) Switch to 802.11a (in the 5.4Ghz range, so the cordless phones will not bother it)
OR
2) Wallpaper the dorm room with tinfoil (has the added benefit of blocking government mind control rays)
Urge to post... fading... fading... RISING!... fading... fading... gone.
Google turned up http://w3.antd.nist.gov/pubs/golmie.pdf. Even though it's about Bluetooth and 802.11b, it might help. Also: http://hardware.mcse.ms/message90850.html for information on bandpass filters. Hope this helps!
US businesses that currently accept chip and PIN/signature
I'm a 3rd year junior, I've since moved off campus but this is my suggestions.
1. The, IMHO,most logical suggestion. A dorm room isn't that big, buy a 50 foot cable. If you insist on keeping a wireless network around, try going for 11a equip. Kinda hard to find but a week or 2 ago, worst buy...er i mean bestbuy had a sale for a dual band 11a/b/g router.
2. See if there is a campus wireless, and if it covers the dorm areas. If yes, convince EVERYONE to kill their AP and use the campus wireless. As for the phones, not much you can do if you're not buying everyone a new phone.
3. You could try a game of "my transmitter is more powerful than yours" and use ext antennas to put out a stronger signal...but not that practical.
Grump
Is it true that more people vote for the winner of American Idol, than vote for the president? -Ali G.
You can't do anything about the interference. But if you get a microwave oven you can turn it on and ruin all their cordless phone reception too. Then everyone will be happy.
like.. could having too many of them in the area cause that?
of course obvious solutions: bigger/better antenna.
world was created 5 seconds before this post as it is.
What does S.O.L. mean?
If you have a microwave you know exactly how to build one. The freq. that a microwave functions at is damn near spot on 2.4 GHz so all you need is several rolls of metal window screen where the mesh size is the same as your microwave.
Oh Yah, you also need to make sure that it is well grounded, you can tie directly to the ground lug of any triple prong outlet, or steam pipe, etc.
Free Flat screen whatevers
-- The morphemes of your disquisition are ascertainable, but they have eschewed an ambit of transpicuous exposition.
First: I'd guess that some of the interference is coming from other 802.11b/g gear, not necessarily cordless phones. It all defaults to channel 6 from the factory, so try 1 or 11. Or load the ETSI firmware and use 14, and just don't tell the FCC.
Second: Try some FHSS gear, it seems tougher in noisy environments than DSSS. The old Proxim RangeLan equipment is cheap.
Third: Get out of 2.4GHz entirely. Go go 5GHz with 802.11a, or 900MHz with older Aironet gear.
Fourth: It's a dorm room, and worse than that, it's an MSU dorm room. What is it, 4x8 feet? Stick with wired. Get a real patch cord that uses stranded conductors, as the solid stuff is too stiff and will stress the connectors.
Obviously, this situation sucks, but it does give the son a dose of reality. Move into a new neighborhood? Contend with interference. Move into a new apartment? Contend with interference. Sounds like a great opportunity to test out his technical and negotiation skills that he'll need once he enters the post-college real world.
My mom always said, "Jim, you're 1 in a million." Given the current population, there are 7000 of me. God help us all!
For the college student, 2 is pretty much the only option available.
Huh? It's probably costing $10k per year in tuition, books, dorm, food, etc. Then another $2k+ for basic computer/AV/electronics gear. So you're telling me a couple of hundred more for superior connectivity is out of the question?
Hang sheets of lead on the walls. Should block out most things.
Devise, Repair, Solve, Build
Nothing you can really do in this case.
However,
my Belkin equipment has a special mode it says you should enable in high-interference environments. My guess is, it either adds additional error correction, or boosts the output, or something, at the expense of a little bit of speed.
You probably already read the AUP for MSUnet. It specifically addresses the issue of NAT devices, a common concern at universities. The issue is that normally a person must register their MAC on the network to gain access. Then any nefarious activity that occurs on the network can be tracked to the individual user who registered that MAC address. For now, let's ignore the possibility of being able to change the MAC address on some ethernet cards.
By introducing a NAT'd device, you open an entry point to the network to anyone, even those not with proper access, and you rely on the good will of these nameless souls not to do bad things in your name. So if anyone ever becomes evil while connected to your basepoint, it becomes your responsibility to deny access to your AP or remove it from the network.
You like splinters in your crotch? -Jon Caldara
It could be due to huge numbers of people "stealing" his wireless. No, really--those cheapie consumer broadband routers don't fare well with more than a handful of simultaneous users. I'll bet a lot of people are turning on their laptops and finding that wonderful little connected icon in the bottom right and not thinking twice. Even with in-room connections, sometimes it's hard to get your ass off that bed :)
I think there is a world market for maybe five personal web logs.
I've been doing some wireless surveys on my campus and one of the cisco geeks pointed out that the best sheilding he had seen for b/g wireless was chain link fence. It's something about the size of the grid being perfect to block that frequency range.
So what you do is have your son go out some night a construction site and aquire 7 or 8 of the sections of the temporary fencing.
Oh really?
FCC Part 15 rules state that this device must accept any interference, including interference that might disrupt its operation.
This means that any other wireless routers, cellphones, microwave ovens, etc... are free to wreak havoc on it, and vice versa.
Having said that, you can always spend more money to upgrade to the newest 802.11 wireless protocols that operate in a different range. It will still be another 6 months before prices drop enough for students without rich parents can afford them.
Honestly, as a young man, I am sure he can tough it out with a CAT5 cable like we did in my day and age, before these new fangled wireless things made life easy. It won't be chic, and it is certainly very old-fashioned, but it gets the job done. Its quite possible your son might never have seen a CAT5 cable before, so now its time for you to show him how Daddy use to do it.
Or you can have Grandpa come down and show him how they did it with 10base2.
Bah! Back in my day we used ARCNET, Twinax, PLIP, or if we were really lucky, SLIP, and WE LIKED IT!!!
Quando Omni Flunkus Moritati
Start using WiFi properly and encourage others to do the same. WiFi should only be used when a wired solution will not work. If the distance is only 10ft and wireless can penetrate it, most likely a wired solution will work.
You're assuming they're running an open access point.
We huddled around a 110 baud acousticoupler, and if you read something that was funny the laughing would generate errors in the connection.
I work in a noc doing cpe (customer provided equipment) support for small companies in pop in downtown Toronto. Since we've introduced cpe enabled wifi, I've turned on snmp polling for stats on connectivity, signal strength etc, and its open my eyes as to where things can go wrong with wifi in a chaotic enviroment. We have about 64 + access points in a building that is less that 300 feet long, and 80 feet wide, that is two stories, and we have no radio interference. 99% of the cases of lost ip transit to wireless endpoints like laptops, bridges or a/ps were due to either Trojans/spyware/malware/viruses swamping the cpe's wan interface, nat process or someone cracking wep and swamping the connection with Kazaa traffic. Either way, I suggest you stick a network sniffer like snort on the wan ethernet interface of the dlink inline (an old p200 w/ 128 megs of ram and an 8gig disk makes a great sniffer, running linux, freebsd or openbsd), and watch what traffic patterns you see. Your son will be able to see what traffic is being used, and will have the tools he needs to take responsiblity for his own connection. Isn't that what great geek dads are supposed to do for their kids ? It might save you a few rolls of tinfoil.
This device is the simplest solution to your problem.
No, I'm not kidding.
I've mastered a new technique employing "direct transcranial wireless transmission." All you need is about a 12' lenghth of aluminum foil, two coat hangers, and a pair of 9v batteries. I just added an extra battery yesterday to boost the signal and now I'm getting 1.1 Mb signals--wait...they're transmitting--from Andromeda, and also Tau Ceti. They...tell me their plans. If you promise not to tell them, I can send you the schematics after I take my meds.
"OH SHIT, THERE'S A HORSE IN THE HOSPITAL!"
My god, you live in a *dorm* and you need wireless networking?
You're the wifi version of the idiots I lived next to in college with GIGANTIC STEREOS jammed into little 8ftx8ft rooms. Did you know ALL music sounds the same when filtered through the low-pass filter known as "the walls"? I didn't!
Yeah, when you're in college, you're king of your world and entitled to everything. Whatever.
Besides, with the wireless, you're just letting that freaky Linux guy next door who wears a cloak see what kind of porn you like to hit it with.
You don't need a cordless phone either, by the way. You live in a damn CLOSET!
(Oops, this was the guy's dad. Adjust pronouns appropriately.)
The 2.4 gHz band is probably toast. WiFi uses spread spectrum, as do some better cordless phones, but the cheap cordless phones just use one chunk of bandwidth and don't care what else is there too. And then any microwave ovens anywhere nearby will scramble all the 2.4 gHz stuff -- and there's certain to be a lot of them close by.
The 5.8 gHz band is probably much less lightly used. This means that 802.11a equipment is much more likely to work. And no microwave ovens to worry about.
900 mHz is another option, but it's likely to have all the same problems (except for microwave ovens), and 900 mHz networking equipment is hard to find (and generally not very good.)
Seriously, the wired ethernet cables that people have been suggesting are your best bet :)
Check Pricewatch, I've repeatedly bought 100-foot lengths of Cat5e for less than $15, including shipping. No reason to spend $1/foot on cable, unless it's the company's money :)
"BSD: Free as in speech. Linux: Free as in beer. Windows 10: Free as in herpes." --Man On Pink Corner in #52607549.
Have you ever thought he might be faking it so he doesn't have to talk to you? Want hime to look after grandma this weekend and suddenly his line drops? Clip the cheeky bugger over the ears, I say.
Who wants to string a wire across the dorm room to the computer in your lap so you can access the network while laying on your bed?
Then go through the hassle of unplugging it and storing it every time you turn your cpu off and on.
It may not seem like that much of an inconvenience, but why put up with it when there's another solution that's possibley, in the long run, less of a hassle.
so true, so true...
As for a solution, try airpwn, it worked wonders for me, everyone stops using wifi after they feel the power of goatse.cx!
GPLv2: I want my rights, I want my phone call! DRM: What use is a phone call, if you are unable to speak?
1) Fire up NetStumbler (or your OS's equivalent) and see which channels are in use. Remeber that 802.11b/g "bleeds" both up and down at least one channel. Pick the "least-busy" channel. Failing that, pick the one with the weakest (i.e. "easiest to clobber") signal.
:-)
2) Depending on your school's policies, see if you can turn on bridging or otherwise share the connection (some schools are okay with it so long as you bridge and don't use NAT). If your connection works, others might use it and shut off their own connections. This probably involves talking to neighbors with their own APs.
3) Talk to a neighbor with an open AP and see if you can use that one rather than your own. Most people are cool about that sort of thing.
4) If you can't share, think about -reducing- the power of your AP, and see if your neighbors are willing to do the same. This is the airspace equivalent to "quiet hours".
5) Almost every new AP supports some sort of "interference robustness" or "microwave-safe mode" or something like that. All it does is reduce your MTU so that -some- of the packets make it through. Either turn this on, or manually reduce your MTU.
6) Think about Bluetooth, 802.11a, or other "alternative" wireless technology. Bluetooth shares the same frequencies, but is often able to get an across-the-room connection even when the wi-fi space is totally screwed up.
--
Remove the magnetron from and old school 1500 wattmicrowave. Mount it in focal point of an old Primestar (or other satellite dish). Install a pistol grip and a trigger and you are good to go. Get a nice long extension cord and sweep the entire dorm with cleansing 2.4ghz waves. As long as you shield you AP before you begin you should be the only one left on the 2.4ghz frequency. Save your rig, it makes a nifty hot dog cooker. One warning, line you shorts with lead before you start so as not to cook your own frank and beans.
SD
PS Don't try this anywhere, ever.
âoeWho knew something as harmless as willful ignorance could end up having real consequences?â
Try a patch, corner, or parabolic reflector located at the access point. It should do the job and if it doesn't you will not have wasted much time or money. Freeantennas has plans. You can use ordinary tin foil or screening to You want to orient the antenna to either block the interference or to project it's stronger coverage over your desired area. If that doesn't use a cat5 cable. -- ecks
You can investigate actual Wi-Fi surveys from wardrivers at wifimaps.com. You can view your location, and see the other access-points in the area -- complete with channel data.
Zhrodague.net - I do projects and stuff too.
here ya go note- it mentions 2.4 Ghz phones.
every day http://en.wikipedia.org/wiki/Special:Random
Search Google for more information, or check out the Linux iwconfig man page.
Since the frequencies overlap... the way to minimize interference is by getting everyone on these 3 channels. 1, 6, or 11
Take charge... assigning channels to each on the floor... keep like channels as far apart (physically) as possible.
Then, using NetStumbler, find the channel that is least busy/least noise (of 1, 6, 11) for your own usage...
I have a wireless router in my dorm room. It is a Netgear WG624. I also have a 2.4 GHz phone in the same room. I notice no interference. Somebody did say to change the channel to a number other than the default 6. Mine is set on 11. One of my friends has a D-Link, he also experiences this problem. I would suggest a new router because it maybe D-Link's problem.
Don't forget that if there are bluetooth devices operating in the area, they act as 802.11 jammers and will make your wireless life hell.
Perhaps a beefed-up IRDA connection would work better? Maintaining LoS is a bitch, though.
Nine out of ten "answers" being modded up in this thread are pointless or worse. ("Get a bigger antenna to reduce interference from phones" -> +4 Insightful?!)
Allocating channels properly (1,6,11) is one of the few suggestions that will actually help.
Dahlmann tightly grips the knife, which he may have no idea how to use, and steps out into the plain.
How big is your dorm room? 12x10? get some cat5 cable, sheesh. Wireless isn't always the answer.
I post links to stuff here
Get a HAM radio license and force them off your signals legally! I remember a slashdot story about some HAM operators doing that.
Search through the archives on your own..
Just get him a 50 foot long patch cable he can use to connect his computer to an RJ45 jack on his wireless router. Voila--no interference *plus* a faster connection. Most dorm rooms are tiny; a cable 25 feet long would probably work fine in most.
The old 900MHz 2MBPS (wavelan) stuff and 900MHz phones are not very popular these days. You might give it a try.
Maybe some leadership experience would do him good. Organize the dorm, set up a limited number of access points. Not much more difficult than organizing a panty raid.
Drag a wire around. How big are the rooms anyway?
Buy a condo. It's a better investment than dorm rent.
Use infrared wireless instead. How big are those dorm rooms anyway?
My kids are off at college but not living in dorms after first year. Both used wire in dorm rooms. How big is a dorm room anyway? They use wireless in the library and other buildngs where the Universitie(s) provide it.
Knock the door off his microwave and wedge a chopstick against the interlock. Put it on a timer so while he is in class nobodys wireles works. They'll all give up after a week or so and he'l have the whole 2.4GHz ISM band to himself.
Line room with Al foil or wire mesh.
Do not look into LASER with remaining eye!
Yes, Part 15 does say that. However, the sentence BEFORE that says "must not CAUSE interference to any other device".
The fact that Part 15 says you have to accept interference doesn't mean you have to roll over and take it, no matter what the interference is. It is referring to *unavoidable* interference.
Also, devices like microwave ovens aren't Part 15. They have their *own* type acceptance, and their own level of acceptable emissions. If a leaky microwave oven is blowing you away, you have recourse.
Comment removed based on user account deletion
place your antenna in the middle of the square dorm ...
room. then cut out a 0.5 m diameter circle from
alu-folie. do this four times. stick the alu circles
in every corner where celling meets walls. should
help to keep your signal in your room. of course
i'm not a radio wave wizard so maybe you'll have
to adjust (e.g. calculate) what the correct size
for the alu-circle in the corner should be. prolly
also depends on where the windows are and the net
floor size of the room etc
yes and the secret goverment base with all the
secret brain control and masses control equipment
does exist. serious would anyone believe that we
have rockets that can reach the moon, a one bomb
that can destroy a whole country but doubt mind
control equipment exists?
...run Linux?!?!?
You didn't say what kind of 'intermittant outages' you were experiencing. Does he have to reboot the access point often? Or is he just suffering from intermittant packet loss?
Most of these cheap AP's have software problems that allow them to crash under ordinary circumstances - but ones not present during the minimal lab testing just before product ship - such as the presence and active use of other manufacturers products. Sometimes, if the manufacturer has an 'unaccpetably high' rma ratio, they issue software patches to address their bugs. Othertimes they don't and leave you stuck with it.
They also are usually more suscptible to power quality issues - much more so than your desktop computer perhaps - and this issue can be addressed by using a quality battery backup power supply (UPS), which will filter the power and ensure you get nothing but good clean juice. Lots of people discount this, but really, you can only ever get out of your electronic devices what you put into them, and power is the key component. No, it won't stop your windows from becomming a spam sending zombie attack drone, but when the freezer downstairs kicks it's compressor on, it'll stop the resulting power sag cold in it's tracks. I have over 150 wireless subscribers in town here and usually when my lights blink I get calls from 5 or 6 all at once saying they can't get online, but the reason is that their broadband routers all hung and need to be powercycled. My business users all took this advice and not one of them has ever had to powercycle anything. Imagine that.