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."

Comments

Few things.

[mindstrm]

1) so-called Wi-Fi, usually 802.11b, uses the 2.4Ghz ism band, not the 900Mhz one. Most wifi is therefore NOT 900Mhz.

2) Of course it's going to be congested! There is a REASON the 2.4Ghz band is where it is. It's dirty, and unlicensed. It was designated in the first place as an ISM band because it's dirty; it's not as commercially attractive as other bands in the same area. The fcc regulations REQUIRE you to accept interference from other devices.

Ehh?

[EchoMirage]

From the article:
Headsets and other gadgets using the Bluetooth standard, newer cordless phones and microwave-powered, energy-saving light bulbs share the 2.4 to 2.483.5 gigahertz frequency range used by Wi-Fi. Household microwave ovens use radio waves in that range to heat leftovers.

802.11b Wi-Fi devices occupy the 2.4 GHz spectrum, not the 900 MHz spectrum as erroneously stated by the article submitter.

802.11a, by comparison, uses the mostly-unoccupied 5 GHz spectrum, making it less prone to interference. It also boasts about 5x the theoretical bandwidth of 802.11b.

Furthermore, there are additional 802.11 hybrids that occupy different frequencies and offer different bandwidths.

Poor Equipment

[Bonker]

The company I work for used a wireless link to get a 45mbit/sec data connection between our two offices for more than a year. Different businesses in the same building initiated wireless links after seeing the sucess we had with ours. One, which was aimed at a nearby wireless ISP was illegally overpowered and wiped out our connection regularly, despite the fact that the dishes weren't even facing the same direction. The other, which made a very short hop, was apparently on poorly configured equipment and would also play merry hell with our shot.

IANAWE(I am not a wireless engineer), but I can't help but feeling that if we're to see the 'unlimited spectrum' as it's been mentioned before, then equipment manufacturers are going to have to do a hell of a lot better job of making wireless kit that minimizes signal bleed.

Re:Poor Equipment

[Cef]

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.

2.4 ghz Co-existence sucks

[PhotoGuy]

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

That is why there is a choice of channels...

[HiyaPower]

The standard 802.11b usually is preconfigured to be on channel 6. Do yourself a favor, change it when you install your network to something else... The average folks will just plug in the WAP and let it run on that channel. You can have a brain and not compete there.