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Is There Too Much Enthusiasm Over Wireless?
lukOh asks: "in the US, 802.11b/g (2.4Ghz) devices use an
83Mhz-wide frequency range; in-use channels spanning 22Mhz and centered on one of 11 5Mhz steps (badly named as "channels"). This means there should be no more that 3 networks in close proximity, 5 'channels' far from each other, to avoid harmful interference. Now, in the middle of the mixed area where I am, the number of usable WLANs (SNR>20dBm) has gone from 10 to an unworkable number of 20, in just one month. Has the community/the market overestimated the practicality of wireless networks? Are we generally relying too much on such a young, IMHO immature technology made on 'startups hope' and broken firmwares? How can this mess possibly be handled in a working environment, especially the moment your boss asks you to give him access to 'the wireless'?"
"Access points can be easily detected, but the same isn't always true for every single client (or Bluetooth device) searching or using a network. Bluetooth itself employs the same 2.4Ghz range with 1Mhz-wide channels and much less power. To avoid interference a device jumps channel-to-channel, when the currently selected one is busy.
Most WLANs are managed by less-than-perfect SOHO access points. Connecting to an AP in such an environment is a gamble (even from 1ft away), especially when: WPA/WPA2 must be used; 802.11g stability is a dream; anywhere up to 7 networks are on the same 'channel' (1 and 11, being the most used, are standard on many devices); and now 'channel wars' are very common (i.e. 2 or more users concurrently hunting to set a free channel for their network, making the entire range unusable for hours)."
Most WLANs are managed by less-than-perfect SOHO access points. Connecting to an AP in such an environment is a gamble (even from 1ft away), especially when: WPA/WPA2 must be used; 802.11g stability is a dream; anywhere up to 7 networks are on the same 'channel' (1 and 11, being the most used, are standard on many devices); and now 'channel wars' are very common (i.e. 2 or more users concurrently hunting to set a free channel for their network, making the entire range unusable for hours)."
The extention of the 802.11b standard into 802.11g is a pain the arse for exactly this reason. All access-points should be limited to work on only channels 1,6 or 11, and rate limited so that anything too far away simply drops off, rather than throttling.
802.11a has a much better frequency spacing (8 non-overlapping channels in most juridstiction, 4 in the others), but many countries won't let you use it outside. The penetrating power at 5GHz is also less than at 2.4GHz.
Has wireless been overhyped? Hell yeah, but all we are seeing is the same problem that we all had when everybody went out and bought a 900Mhz cordless phone.
We need to either compress the channel bandwidth (OFDM with few channels around the center frequency), which would give less bandwidth per channel, extend the number of non-overlapping channels available. Jacking up the frequency would give better overall throughput and less channel conflict at the cost of range.
Norman Cook's Ode to Sl
And for a good reason, it is so cool to be able to work from anywhere. When I was in college. We had alot of tables with network connections. But with so much student they were always taken. We could only work at places that had no plugs.
So the hotspot were my savior. Now when I work in my office, I don't need to mess with cable anymore(beside AC or mouse). I would never get back to the "old" way now.
One day the wireless turned out not to work very well. We didn't understand it at first. Cause it was working so well for so long. We discovered that 2 other hotspot has been install near our own, so they were 4 wifi network near each other.
They was somekind of interference. We changed channel to an unused one instead of using our default channel 6. It helped, but the article is right. They should have tough of the hype. They could prevented this. Now it will get worst. And the only solution is upgrade to a newer better standard...
But for now, we moved to a new business adress, and we are the only one using wifi. Joy to my world.
It's funny how I make sense to others and not myself...
"Ummmm. Can you remind me what the vt100 equivalents of eBay, Google and Skype were"
Usenet, gopher and talk/ntalk??:-)
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lets get one thing straight the narrow bands of license exempt spectrum are a tiny portion of total usable spectrum (the end of total usable spectrum is iirc somewhere in the tens of GHZ atm).
and they are generally a good thing because they allow normal people to use some radio based equipment without huge licensing hassles.
if your favorite unlicensed band becomes too crowded you have a few options
1: move to another unlicensed band thats less crowded(e.g. move to 802.11a)
2: buy licensed bandwidth (expensive but once you've bought it you have the law on your side if people interfere)
3: cooperate with other users of the unlicensed bandwidth
4: move to a wired system
5: put up a radio screen arround your building (expensive and obviously only possible indoors).
your post seemed to imply you thought unregulated bandwidth is a bad thing, its not it allows people to do things easilly that would be prohibitively expensive for most otherwise.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
-"A lot of FHSS devices are used in warehouses and the like, as FHSS is fairly immune to noise, but had a much lower limit on it's speed (2 Mbps or slightly more if you go vendor specific)." Uhmm, no. Frequency hopping (FH) is no more immune to noise than any other technique. This is because noise power tends to be spread equally over all frequencies (white noise) so there is no benefit in hopping from one frequency to another. It is however more immune to interference since this (sometimes) tends to be unequally distributed over frequency. -"That's not to say it's not possible though, and many FHSS networks have very poor security (as they haven't gone further than WEP with 128 bit keys)." This is misleading. If there's security issues then they may be due to the choice of protocol, encryption, hop codes, etc, but not to the use of FH itself. In fact, with proper choice of hop codes, security is considered to be one the strengths of FH. This is one reason for its common usage in military communication systems (difficult to intercept a signal transmitted at a frequency which is varied over time in an 'apparently' unpredictable manner).
"regulated" is not the same as "owned and rented out".
My Karma: ran over your Dogma
StrawberryFrog
Your using a Linksys router I'll bet, there is an issue they have with about every 10 minutes they have timeout errors - I know this because I play Everquest upstairs while my wireless network is downstairs. Back before linksys fixed their firmware (and I don't think it still has the problem) the solution was specifying a port range, but updating your firmware should fix it - if not, take a look through the forums of your router - if it's not a Linksys, it may be a similar problem with your brand.