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Wireless Congestion
AllMightyPaul writes "An article on CNN describes the congestion experienced by many users of wireless networks as more and more people begin to use them at home and at work. The unregulated frequencies between 902 and 928, where most Wi-Fi devices operate, sees a lot of traffic, apparently."
It'd be interesting to see some mobile spectrum analysis of frequency usage over geographic areas, to see if that plans out -- map spectrum emissions and see if there's an aberrant concentration in spots. Might not be terrifically useful, but cool data.
Aside from broad deployment of spread spectrum for future RF-emitting gadgets (the ones not using it already), it'd be helpful if devices like 802.11b access points could indicate when they're having interference problems, so as to distinguish these problems from those of topography, incorrectly installed antennas, hordes of evil lurking microwave ovens, etc.
I'm not worried. I am posting this comment from a laptop with 802.11b, while a 1.3KW microwave oven 10 feet away is cooking my dinner at full power. At the same time, my laptop is playing MP3s in the most gluttonous manner: using a remote esd connection to a box hooked up to a stereo, without any problems.
Now how am I to take seriously the rest of the points that the article makes, if even the one most obvious and easy to verify is wrong in this one instance?
Tsunami -- You can't bring a good wave down!
I have a 2.4 ghz IEEE 802.11 wireless network in our house. Works great. (All Lucent cards.)
We have a 2.4 ghz phone, with also works great, but when we're on the phone, the throughput on the wireless lan goes down, and similarly, if there's a lot of wireless lan traffic, the phone gets interference. Tried different channels.
Tried out a wireless video relay from Radio Shack which uses 2.4 ghz. The wireless lan (even idle) causes regular noise on the screen, making it unusable. It went back.
Most annoying of all, when our microwave is on, the wireless lan loses most packets, and is almost unusable in the kitchen (and some other places).
The frequency hopping and co-existence in this band doesn't seem to work out as well in practice as it does in theory, unfortunately.
-me
Love many, trust a few, do harm to none.
With point to point links you really need to evaluate antennas and your area. Many people use antennas with a wider radiation distribution pattern than is necessary, simply because it does the job. A number of cheaper antennas also have terrible front-to-back noise ratio, so noise from behind or the side of the antenna can really affect the signal. Also remember that many antennas allow you to orient the polarisation of the signal by the way they are mounted, and some antennas even have circular polarisation.
With general network setups (eg: an office) many people have a tendancy to put an AP on the edge of the building, particularly in warehouses (simply because there is little else to support it). Semi-directional antennas (with 60-180 degree coverage patterns) are VERY useful for walls and corners, and usually have a higher gain in the direction you want (away from the wall or corner, into your business). The less signal that escapes your premesis, the less chance of interference, and also the harder it is to get an outside connection (ie: war driving).
If your setup doesn't allow for outside interference, and is very succeptable to it, you'll always have problems.
(somewhat informative: http://www.freespaceoptics.org -- one of many sites on the topic, but one which had a nice pic near the top ;) )
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... I think it will happen. Wait til last year's optical gear is on clearance at Walmart ;)
The site I can't find quickly (anyone?) is one that I know has been mentioned on Slashdot a few times, home-built optical transmitters (In the Czech republic, IIRC) using modified ethernet cards and powerful LEDs to beam multi-kilometer distances
5 years ago I would not have guessed how widespread and cheap 802.11 stuff would be today; right now, you (point of reference, Americans in the lower 48) can get an 802.11 base station for under $100. Glut isn't quite the right word, but lets say there's *a lot* of somewhat decent, moderately versatile wireless gear available for what is in 1st countries not a huge chunk of disposable income, at least for folks middle-class-and-up. The cost of 7 cds gets a working base station
Wouldn't it be nice to see a similar flood of products for optical gear? Yes, there will be lawsuits (eye damage! you hurt my eye!), and ugly warning labels, and ISP crackdowns for retransmission and who knows what else, but
timothy
jrnl: http://tinyurl.com/c2l8yr / foes: http://tinyurl.com/ckjno5
My pop solved this problem last year, with copper mesh underneath the new siding he had put on his house. He also limited the nework to only a smaller area, running printers and such. And the copper mesh wasnt all that expensive. He now is interference free. The trouble is, he also has to go outside to use his cellphone, and the cordless phone wont work outside the house. Trade-offs are a bitch.
Stupid Humans.....
Check it out, Zhrodague WiFi Mapserver is online, and almost ready for prime-time. We have a US map loaded, and more detailed maps for Pennsylvania, and Massachusetts. Upload your netstumbler data, and see it plotted on the map. Part of the Pittsburgh Wireless Community.