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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.?"
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.
I don't know I picked up a Proxim Harmony access point (802.11a) for $10 on Ebay, pretty much the most affordable access point I have ever found.
Sorry, teleporters just kill you and then make a copy. A perfect, soul-less copy.
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.
Most schools, including mine, ban wireless routers for this reason. They want to track who does what with what computer on the school network. They also ban regular wired routers too, for the same reasons. You might want to check to see if Michigan even allows wireless routers - they probably don't. While a wired router is hard for them to find, my school will sniff out student-run wireless and bust people for running them. So the first thing I would do is just make sure you aren't wasting your time trying to get this to work.
Even if they do allow wireless routers, you might want to re-evaluate just how badly he needs that wireless. Dorm rooms aren't that big - just buy a long cable. Or buy a cheap hub and run a cable to the desk, to the bed, and anywhere else he's going to use a laptop. One of my roommates did just that, worked fine. Lastly, you might just try unplugging your router and seeing if you can pick the school's wireless if they have it. If he's really lucky, he might get a good signal from some other sucker's wireless router. In which he can download as much music, movies, warez, and p0rn as he wants, and if the RIAA/MPAA/BSA comes around, or if the ResNet people get annoyed at the excessive bandwidth use - they'll bust the poor guy who registered the MAC address on that router.
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.
True, but it's a pain in the butt to install it all. Have one of your buddies convince your floormates to "prank" you, by covering your entire room in aluminum foil. Act really pissed, and then never take it down.