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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."
kind of like cable, doesn't it?
Seems to me that an article about RF congestion was posted earlier today...
According to the article, WiFi uses the 2.4GHz range ("2.4 to 2.483.5 gigahertz")...
Good idea to mirror it because CNN has really been having bandwidth problems lately.
Whore.
Sounds like a bunch of FUD. Yes, there were some occasional problems. How about the incredible convenience this technology enabled, and the many people and organizations that were able to benefit? The article sounds like it was written by one of those negative people that always stand on the sidelines and comment about why things won't work, without trying to help. Pfft.
Tsunami -- You can't bring a good wave down!
Hmmm, these problems all relate to 802.llb... 802.11a isn't as widespread yet, but it is faster... any idea if it is also less prone to these collisions? If so, maybe it would have better effectiveness in adoption.
"PC Load Letter? What the $@#% does that mean?!"
I know that there have been reports of people using cell-phone amplifiers getting cancer -- I wonder if people will worry more about their children growing extra limbs than connection interference ... ?
However, CNN was not credited, nor was the date of publication give, nor the original URL. One should at least know who and what is being mirrored.
Because I live in a four story house that I am renting and, as there are computers on each floor, I would prefer wireless to having CAT-5 everywhere or drilling through walls that don't belong to me.
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.
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.
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.
The next Slashdot story will be ready soon, but subscribers can beat the rush and slashdot the links early!
Coming up in other news, bear shits in woods shocker, and pope admits to Catholicism.
What the hell about this article about the false theory of spectrum scarcity no less then 2 hours ago?
when the network gets congested. It's not a gradual thing, either... once you get two or three transceivers on or a point or two away from the same band you might as well just plug into a phone line for your networking. I've got a friend working at a lab that's looking into a couple of different technologies to try to alleviate this. They believe that they can compress the signal into smaller wavelets in order to fit more in a given airspace, which if successful I guess will increase threefold the amount of equipment you can get on a band (harmonics still apply, however). The other plan is to use inverse wavelengths to get information that is precisely the opposite of a packet out synchronously with the packet. While this can only be done when there is data in the queue in opposite to data about to be sent over the air, this happens quite often with binary data (being 0s and 1s -- you can't get much more opposite on the spectrum than that!) so by tinkering with the packet lengths in light of this concept they're hoping to eke a bit more performance out of the medium. I wasn't given specifics, but I'd assume there's a great deal more (proprietary and patented) to these technologies. So hope's on the horizon.
I hope this first post from my wireless network makes it. I'm seeing a bit of lag at the moment so maybe I'll get second or something.
...we turned this "congestion" into "p2p cooperation" by using the same protocol in which we all routed each other's data.. rather than dreading interference, you'd PRAY that the guy a block away set up a wireless network, so you could hop through him to that evasive Internet access point...
You can run but you can't hide, except, apparently, along the Afghan-Pakistani border.
And you're not smart enough to avoid tripping on the cord?
I would prefer wireless to having CAT-5 everywhere or drilling through walls that don't belong to me.
But that's the fun part.....
Like all resources, it will be offered at little or no cost until it becomes sufficiently limited, at which point the cost to utilize the resource will increase, and provision of the service will become proffitable, so we will see the end of community wireless networks, and the re-emergence of for-proffit networks, where access is restricted and the frequencies used will only be available to subscribers.
--CTH
--Got Lists? | Top 95 Star Wars Line
Do you understand sarcasm?
What is the point of having a laptop if you are going to anchor yourself to a certain spot using a network cable?
I use wireless at home exclusively for my laptop. I can use it by the pool, I can use it in my bedroom, I can use it in my living room...
I think the author needs to get in touch with the times! ;-)
There is an amateur radio band between 902 and I think 908 MHz, the 33cM band. Certainly not ungregulated.
-- Note: If you don't agree with me, don't bother replying. I won't read it.
...of this story
People who disagree with you are not automatically evil, greedy, or stupid.
Careful reading will indicate the discussion is of providers of wireless network access. As for offering pieces of the spectrum, that's the domain of the FCC, but is not the focus of this discussion.
--Got Lists? | Top 95 Star Wars Line
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.
From the article: "His solution: Get his neighbors to space out frequencies they use."
... let them all share the congested default frequency and just move yourself as far off in the other direction as possible. :) After all, he's the one that thought of it.
Screw the neighbors
And you're not smart enough to avoid tripping on the cord?
Some of us actually like to live in a clean environment, a concept that many hygienically challenged people can't quite comprehend. Walking over cords is probably no big deal for someone who's used to stepping over animal feces while walking from one room to another. But for those of us who aren't "ghetto", wireless is a nice option.
And is an unlicensed user of the spectrum. Fortunately current technology can compensate.
At 900 MHz Government and vehicle location are primary, and amatuers are among the secondary authorized users. Part 15 devices just add to the noise that other services must overcome.
In both bands, amatuer operations are swamped, if low power, by the increase in the noise floor. However, amatuers can operate on those bands with enough power using the same spread spectrum scheme such that the WiFi would be useless for PArt 15 devices. But its unlikely given the nature of the amatuer radio service (recently the FCC relaxed the allowable spread spectrum/frequency hopping restrictions on amatuers).
This is where that portion of the FCC regs. for Part 15 devices is critical, in that they must not create interference for the licensed users of the spectrum and must accept interference from them. Not an exact quote, but you get the drift.
In a nutshell, if you use unlicensed devices in spectrum where other services are authorized for higher power, you get what you'd expect. Now 5GHz is a great place to be! BTW when I key up on 2.4 GHz with 10 watts, my 802.11b network shuts down pretty hard. With only 50 feet or so of seperation the front end of the WiFi receivers gets overloaded even though I am not all that close in frequency, it is just the radio circuitry in the WiFi devices is just barely adequate so they can meet their price point and comply with the FCC regs. Better frequency agile receivers could be put in the devices and most likely will be as more devices crowd in. Also automatic power control will get better and the potentially they'll create a third scheme for the spread spectrum use that is more adaptive and as such would accomadate more users.
Last, everyone knows that they can change the channel their network is on, right. I have found several swamped WiFi networks all clashing on channel 1 when there was plenty of usable spectrum up the band. (Powerbooks are great portable diagnostic tools even though the UI is cheesy for the Airport software and the third party tools are scarce due to lack of internal Airport info.)
- Tjp
I am in wallow with my inner money grubbing capitalistic pig. ... Oink!
decision to get into powerline communications.
Built using ac wiring in house, aptc. etc. no
RF componentsof I/O.
Inventor years ago prototyped solved ac humming
and bi directional analog/digital signal I/O
transfer protocall. Mothballed because he likes
to create new stuff, so shelved. If interested
in technology he might be interested in selling
it.
www.colossalstorage.net
go to biography page
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.
Excuse me for erroneously stating that it was 902 to 928MHz. So I made a mistake, shoot me.
Stuff like this is already happening, in some form, in several cities around the US. Check out Seattle Wireless, Austin Wireless, NYC Wireless, and FreeNetworks ...
I don't believe the 2.4 GHz ham band overlaps with the ISM band in the USA - It's directly adjacent, I think.
The Australian (Maybe another country) 2.4 GHz ISM band is a different story - There's an article for hams on hacking old Proxim Symphony cards that said that if you send in a photocopy of your ham license, Proxim would send you a card normally only legal in Australia.
retrorocket.o not found, launch anyway?
"I know that there have been reports of people using cell-phone amplifiers getting cancer "
There have been reports of people being kidnapped by space aliens.
But barring any evidence, neither seems to be true.
He was trying to make a joke. A bad one, but he did it honestly, and I think that deserves a pity karma point.
Signed,
Someone at the karma cap and who earned it honestly.
What's so special about these presentations?
Yes - a cellular/trunked model will enable greater use of spectrum. This has been well known for the last twenty years.
Yes - spread spectrum/ultra-wide band allows re-use of the same spectrum.
BUT the price you pay (for cellular or spread spectrum) is gradual degradation of service with increased users.
Yes - radio waves do "pass through one another" allowing spectrum re-use, and that's been known since beam antennas came into use in 1919.
These presentations are simply examples of special pleading by commercial interests. Some corporations believe that the law of gravity could be repealed if they lobby hard enough. Everyone wants a chunk of the radio spectrum and non-one wants to pay for it or show responsibility to other users.
(somewhat informative: http://www.freespaceoptics.org -- one of many sites on the topic, but one which had a nice pic near the top ;) )
...
...
... 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
Sorry. Needed to be said.
True this could be a problem in a city situation but in a rural or country I would think this would be minimal. Think about all the gadgets working on the 900 MHz band...Cybiko Computer,Vtech Vlink, Cordless Phones, Wireless Headphones, Video Transmitters work on the 900 MHz. This would seem to be a lot of people making their homes vulnerable to a lot of eavesdroppers. We need to get rid of everything runing on analog mode of communcations to ALL digital.
By searching 'optical link' in .cz on (advanced) Google, I found http://atrey.karlin.mff.cuni.cz/~clock/twibright/r onja/ . /., I found http://slashdot.org/article.pl?sid=01/12/22/143221 1&mode=thread&tid=137
Searching 'ronja' on
Such a configuration protocol would require authenticating access points across organizational boundaries to avoid Denial of Service attacks or one wireless user to maliciously exploit the protocol to gain more bandwidth over neighboring users.
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.
The site you are looking for is Twibright Labs : Ronja, good luck ;).
www.baleareswireless.net
We did our own design some times ago, if you are interested, have a look at: http://strike.wu-wien.ac.at/~dusty/projekte/laserl ink/index.shtml
Although solutions like this work and are much faster than 802.11 solutions (100Mbit are no problem), they have the following problems:
- weather dependend
- high precision adjustments
- obstacles (birds, insects) hinder the transmission
They are a lot harder to set up than a simple 802.11 solution, moreover they only work point-to-point.
Anyway, the eye-safety thing is no issue at all as one can easily make a 20mW Laser that reaches > 10km eye-safe with a simple beam expander.
Do-it-yourself designs are probably also possible by the use of transceivers of Micro Linear - but I just can't find time...
This is exactly like the CB radio craze, people will next start running linear amps to power through the conjestion. Breaker, breaker, how about you Rubber Duck, ya got your ears on?
Microwave grape racing
Not that i like governmental involvement, but perhaps this is one time the FCC should have been involved.
Left to their own, people dont share..
---- Booth was a patriot ----
Anyone ever heard of Usurf America?
Well I used to work for them and they were trying to bring WiFi to the consumer at about the same rate per monthas DSL/Cable.
It's funny that it didn't take off, but mismanagement of company resources and firing your entire Tech. Support Dept. Doesn't help.
It seems like many of the microwave devices are of somewhat low quality anyway, I recall the connection was supposed to have 1.5 MBps up and down, but was never faster than a 256/256 DSL. On top of that data loss and corruption was prolific.
I think these companies should leave WiFi to Cisco (w0rd to your 802.11b) and research even higher frequencies so that in 10 years when the demand increases we wont all think back to the days of AOL 3.0 and it's loverly 26.4 KBps connections...
Linux is dead.
LU