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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.
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.
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?
Sadly Outta Luck
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.
> Sadly Outta Luck
Really? Seriously, I've always heard/said "Shit outta luck" , which really doesn't make any more sense, except that there is a reason to abbreviate it. Once you say it a million times tho' it doesn't seem to be anything odd.
Not that I'd claim my version is the authority however.
"...In your answer, ignore facts. Just go with what feels true..."
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.
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
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.)
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.
Absolutely. I just disagree with the "you have to live it the hardest way possible so you can appreciate when things are better" approach. You may learn something in the process, but is it worth the price? Considering how little time we have on this earth, wasting the best years of it making burgers or cleaning toilets when you don't have to, when you could easily be enjoying it all instead, seems like an insult to life itself. Now if you have no choice about it, fair enough, but if you do...
Daniel
Carpe Diem
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.
--
Yup, I see where you're coming from. But I suspect there's more to life than just pleasure (I believe them there hedonists disagree with that statement). The fact this guy paid his way thru college working at McD*****s demonstrates more discipline than I had during my college years. Having said that, I wouldn't have done it any different - each to their own.
Stuck down a hole! In the middle of the night! With an owl!
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
This was obviously years ago. In this day and time, tuition and other fees even at state schools are so high, and minimum wage is still low, that it is no longer possible to work your way through school. It is admirable that people are willing to work so hard at the same time they are getting an education. Unfortunately now, all that seems to get for students is a lot of debt that they will be paying off forever.
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
Right.. Someone who needs a $6 ethernet cable from Cables R Us should instead buy a $15 bulk spool of CAT5 cable, a $10 box of connectors, and a $15 crimper tool to put the connectors on the cable. And then they can use the box of leftover cable as a nice footstool, and the crimper makes a nice paperweight.
Sheesh.
Like I'm concerned with what is a hassle for you. Sorry but wanting to browse porn in the comfort of your bed isn't a good enough reason for clogging my airwaves.
Err no, overall I ate healthier than the average student. Sure I ate McDonalds when working there, but most of my meals where elsewhere. I cook for myself, and I always made sure they were well balanced. My health is just fine. Better than many others my age in fact, in part because I've always avoided junk food, and when I did have it, just a little bit.
I also don't drink, and I never could stand crowds/parties. These two are major time and money wasters for the average kid. Mind you have to make your own choices. I have nothing against someone who chooses to enjoy school years and pay for it latter. That wasn't my choice. I'm annoyed when someone claims only the rich can get through school paying for it themselves, cause I did it.
I don't have a significant other. I'm still looking. Then again "everyone" knows that for the typical /. geek this is normal. :)