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Has 2.4 GHz Reached Maximum Capacity?
An anonymous reader writes "There's been a lot of talk lately about the concept of Personal Area Networks. At CES Intel and Connectify both released software that turns Windows laptops into Access Points for file transfers, wirelessly syncing pictures from cameras, and Internet sharing. This is good, maybe great, if you're a road warrior, but what about the rest of us holed up in apartment buildings and small neighborhoods? We already have to deal with the wireless chatter of the 50 or so other Linksys routers in the vicinity. What will happen when every laptop also acts as a software router? To add fuel to the fire, Intel and Netgear also announced the Push2TV device that allows you to stream your display, including Netflix videos straight to your television. Isn't this going to kill lower powered 2.4 GHz devices, like Bluetooth mice and headsets? When does the 2.4 GHz band collapse completely? Why can't we push all this short range, high bandwidth stuff onto 5 GHz?"
Pretty much every manufacturer sets the default power output levels to FUCKING LOUD. This means that I can get a clean signal from your router 100m away. Worse yet, most channels have overlapping frequencies with one or two of their neighbours on either side.
----
Go canucks, habs, and sens!
Wow, yea. That's a huge frustration of mine. I'm in an apartment building and our only internet option is Verizon FiOs and they give you a Wifi Router that you use with your service... So EVERYONE is using the same device using the same frequencies. I've had worse experiences with Wifi before, but it is really frustrating at times. When I browse nearby access points the list is out of control.
Hard wiring is not really an option here either. Oh well. At least I got my Xbox plugged in.
The problem is each technology is developed without consideration for large numbers of concurrent devices using the same spectrum. Between encryption, poor handshaking, EMI from non-compliant devices, and attempts by manufacturers to overpower their devices with turbo this or ultra that, the end result is that in high device density areas, the technology becomes nearly useless. This is actually the FCC's fault -- they haven't allocated a large chunk of bandwidth exclusively for consumer-based hardware that provided packet-based network services that requires licensing and certification to use. The 2.4GHz band is like CB Radio -- sure, it's illegal to use a 500 watt transmitter on your mobile rig, but since everybody else and their dog uses it, you should too.
Manufacturers need to come up with protocols that allow the use of strong encryption AND still allow traffic management and QoS. In other words, stop setting up a bazillion different networks: There is one network per channel. Encryption is enabled by default, and that key determines whether which packets can be decrypted. That way, all the header information and link-level stuff that's essential for management is still available, but a reasonable level of privacy is still possible.
#fuckbeta #iamslashdot #dicemustdie
Soon it will be so hammered that we'll all be back to dial-up speeds anyways. That's what we all wanted, isn't it?
The more devices will be on 2.4 GHz, the longer I will be alone on my frequency (5.2 GHz) for my appartment's wifi network. 5 GHz hardware is already there. Good for me if most people still choose 2.4 GHz only hardware.
I think some lady in the UK got in trouble for that.
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
God help you if you want to use your microwave. You'll kill the connection to every device in your house.
"Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
Why can't we push all this short range, high bandwidth stuff onto 5 GHz?
pretty simple really, because people are tight-arses and wont pay extra for the licencing to use non-ism spectrum
TIAEAE!
To AutoPwn!
If you're in a place with too much WiFi noise, try using the Japanese-only channel 14 - it doesn't overlap with any other channels, and you're pretty much guaranteed to be the only person using it. DD-WRT and other alternative firmwares will broadcast on 14, and Windows just requires a simple registry hack to receive on 14. Macs, I believe, can connect without hassle. It's technically illegal, but the likelihood of being caught is pretty much nil. I've still never found an explanation for what this frequency is used for in the US, if anything.
Router? I never ever met 'er.
Since I _don't_ deal with a lot of Windows PCs, I _am_ running everything on 5.0 GHz. Well, OK, there's a "guest WiFi" at 2.4 GHz for friends, but I don't care if that's broken.
Most PCs I've seen with 802.11n only have the 2.4GHz support, and same with a lot of add-on cards and access points. The dual-band stuff is starting to be a little easier to get, though still a bit of a price-premium. Of course, since my machines are either Macs on Wi-Fi or Linux on gigabit copper, I'm already used to a price premium.
However, there's a good side effect of this: a certain eggy on-line store had a whole bunch of refurbished Netgear 5.0 GHz _only_ access points/bridges on for less than $40. So the couple of devices I have that don't do WAP and/or don't do 5.0 GHz are now using those things. Similarly, I set up a friend's office to use one so his Macs aren't drowned out by all the 2.4 GHz chatter in the area. (Downtown, right beside a condo and hotel, across the road from an office building... and almost everyone on channel 1, too.)
Heck, $40 is less than the price of a USB 802.11n adapter. So I bought a couple extra just in case.
So, if everyone else would just _stay off_ 5.0 GHz, I'll be very happy.
Yup, none of the access points are actually smart enough to switch channels and optimize frequency/power usage. So you end-up with the problem I encountered this December, when a neighbor across the way got a wireless router, and suddenly my internet stopped working. You couldn't even *see* my access point anymore, it was just overpowered.
My access point configuration was set to "Auto," but this just meant it kept trying to use channel 1 like an idiot. So I forced it to use channel 6, and the problem was solved.
But this isn't how things should be. The devices and the protocol should be smart enough to optimize spectrum, both by analyzing the noise at various frequencies and choosing the band with the least automatically, and by playing nice with other devices and dialing-down the power to that needed by the connected device furthest from the access point.
Too bad the above is just a pipe dream. I can't imagine how bad it is living in dense residential/apartments, where these users still don't know how to configure things, but there are 2 dozen within range instead of 5.
Man is the animal that laughs.
And occasionally whores for Karma.
2.4Ghz raises the temperature of dihydrogen monoxide molecules, so it's also contributing to global warming!
Ah yes, the quaint wire: Your own personal air domain, a veritable Ether network. Copper's getting scarce and we'll never run out of glass, but optical transceivers are still thousands of dollars. It's getting cramped on this little planet!
slashdot: where everyone yells sarcastic metaphors to themselves to understand the issue
Boom! Headshot.
the reason so many things like 802.11b/g/n, bluetooth, cordless phones, etc are all on the 2.4ghz band is by comparison to other bandwidths, it's largely unregulated, meaning they can do what they want (within reason). Going to 5.8 or 6.0 would be nice, but there are stricter regs on there, and so they can't make / sell features like "extended range" or hi powered antennas, because they're illegal. Until someone manages to invent Wifi over subspace, we're probably screwed.
Yup, none of the access points are actually smart enough to switch channels and optimize frequency/power usage. So you end-up with the problem I encountered this December, when a neighbor across the way got a wireless router, and suddenly my internet stopped working. You couldn't even *see* my access point anymore, it was just overpowered.
My access point configuration was set to "Auto," but this just meant it kept trying to use channel 1 like an idiot. So I forced it to use channel 6, and the problem was solved.
But this isn't how things should be. The devices and the protocol should be smart enough to optimize spectrum, both by analyzing the noise at various frequencies and choosing the band with the least automatically, and by playing nice with other devices and dialing-down the power to that needed by the connected device furthest from the access point.
Too bad the above is just a pipe dream. I can't imagine how bad it is living in dense residential/apartments, where these users still don't know how to configure things, but there are 2 dozen within range instead of 5.
That all works in my favor. Nearly everyone in my complex has their router set to channel 6 or something. I set mine to channel 1 and I've got all the reception I could ask for!
-Taylor
Worldwide Military budgets: $2100 billion. Worldwide Space Exploration budgets: $38 billion. Really, world? Really?
Use aircrack to crack _all_ the WEP keys.
Share with the cool people (who will all cancel service).
Instant spectrum decongestion.
If that is not enough simply post the list of access points/keys in a public place.
It doesn't matter if people cancel service because they realize they can get it for free or because they've been hacked and become paranoid.
BTW ATT's 2wire modems have the WEP key printed on the bottom (and IIRC the key can't be changed).
If you see a 2wire* network available you have free internet.
I need a booster antenna, but I'm on acreage.
John McAfee 'It was like that time I hired that Bangkok prostitute; to do my taxes, while I fucked my accountant'
It is fun to watch a spectrum analyzer when someone fires up a microwave. Old cordless phones are entertaining too. One is a multi-megaton nuke, the other a tac-nuke.
You'll be comforted to know that ZigBee devices, and other devices that conform to the IEEE 802.15.4 standard, do this today, and have done so since 2003.
The second part of your wish, that devices dial-down their power to the minimum needed, is certainly possible, but requires that the receiving device send an RSSI (Received Signal Strength Indication) or, better, an RQI (Received Quality Indication) value back to the transmitting device (perhaps as part of the ACK), and that the transmitting device be capable of lowering its transmit power in the first place (it's an extra expense). I don't know of any protocol that does this (other than CDMA protocols, for a different reason), although I expect newer protocols will -- but to save power (extend battery life), not to reduce spectral pollution.
The problem is dumb receivers, not lack of spectrum.
Channel capacity is determined by the MIMO form of Shannon's Theorem. Add more antennas and smarter processing in the receivers, and the capacity in a channel with lots of multipath (eg. in an apartment) increases approximately linearly.
The problem is that most hardware is a decade (or more) behind state of the art, and that people aren't prepared to pay for a more complex, and costly receiver.
How do these "personal area networks" differ from ad hoc networks?
http://ihatehate.wordpress.com
Wifi Troubleshooting with an analyzer tool.
http://www.youtube.com/watch?v=8eOByjhx2oY
http://www.youtube.com/watch?v=MG48woHjzko
The first is 6 minutes introducing the app. The second shows some waveform stuff.
Pretty much every manufacturer sets the default power output levels to FUCKING LOUD.
Well, not quite all of them. One of the main benefits with tinkering with DD-WRT on Linksys b/g hardware is being able to boost the output from the rather puny(but effective for most) factory 28mW to well over 200mW. Makes for some pretty expansive WDS setups, and a HELL of a lot cheaper than the higher end commercial hardware...
Besides the FCC specs that WiFi devices meet (which are really a fairly bare minimum to avoid really crappy interference), manufacturers take some time to make sure their devices behave. You can be certain Cisco pays attention, and other well-regarded makers, because they intend for their enterprise clients to deploy these in a mesh and will definitely suffer if they are out of spec.
Now, there are plenty of shady outfits, but since everyone pretty much uses the same few radio chipsets, the makers of those chips do their work and produce decent product. No one wants to take back a few thousand routers because they suck so bad they can't live with anything. Besides, does anyone buy D-Link routers any more after their NNTP fiasco? Well, actually, we have short memories, and there is fresh meat being minted every day.
Claiming this is a technical failure by the manufacturers is bogus. More likely, the WiFi spec doesn't really accomodate an infestation of routers. There just aren't enough channel spacing options to solve this in WiFi, and I doubt there is a fix beyond a new spec.
Hey, that's it, call IEEE! We need a new 5GHz or higher spec, dudes. We can wait 4 or 5 years. get on it, ok?
Not that going to higher bandwidth will solve range problems. It's a morass of options and expectations.
deleting the extra space after periods so i can stay relevant, yeah.
Is that really true? I have two access points (CH 1 & 6) and I don't seem to have an issue with microwaves, cordless phones, or anything.
The issue being, of course, if your currently connected "closest device" is in the living room near the router and you want to connect from your bedroom. You'll have to enter the SSID and channel manually because your bedroom device won't hear any broadcasts.
And, of course, when you connect from your bedroom the power will go up and may start interfering with your neighbor.
Yes, 802.11n can operate in 2.4, 5.8, or both.
Parenthetically, I recently purchase a Bullet M and outdoor antenna from Ubiquiti, and wanting to avoid the whole 2.4GHz zoo, I bought the 5GHz version. This was serendipitous, I thought, when I recently had my internet suspended (bad Telus). Not fearing, I got up on the roof with my 802.11n laptop to search for signals from charitable neighbours. Enabling just 2.4GHz mode on the laptop I could pick up around 10 APs. Switching to 5GHz-only mode, not a single one! So yeah, 5GHz appears to be really good for avoiding competition, not so good if you were hoping to easedrop :(
I am literally 3000 tokens away from the chaotic crossbow --Stephen
Well, not quite all of them. One of the main benefits with tinkering with DD-WRT on Linksys b/g hardware is being able to boost the output from the rather puny(but effective for most) factory 28mW to well over 200mW. Makes for some pretty expansive WDS setups, and a HELL of a lot cheaper than the higher end commercial hardware.../i.
DD-WRT's power settings are great. For setting the power level lower...
Don't use them to set the power levels higher than the chipset's specs. The signal to noise ratio drops. You're just sending out the same data, louder, but with a correspondingly increased amount of background noise. You're not improving your connection, and damaging everybody elses'.
After all, I am strangely colored.
Yep. Problems like this are what created the FCC and licensed spectrum in the first place.
So what you're saying is DD-WRT goes to 11?
I don't see how that helps solve the 'loudness' problem for anyone but yourself, which really doesn't solve the problem at all.
Reminds me of a certain Vice President of Hayes ranting how 9600 baud was the ABSOLUTE LIMIT of copper and how US Robotics pushing 14.4 was not stable or reliable because it was violating the physics of the copper medium.
I will not be pushed, filed, stamped, indexed, briefed, debriefed or numbered. My life is my own.
"Why can't we push all this short range, high bandwidth stuff onto 5GHz?"
I really wish you wouldn't. I prefer to keep the 5GHz band wide-open for the unimpeded use of my own 5GHz devices. I bought them specifically to avoid 2.4GHz clutter!
Is that why my wireless mouse acts up? theres 34 access points within range of my laptop, let alone any other wireless devices.
O.o
A lot of the issue with running wires is the cost. Wireless, there are no holes to cut in the wall, no climbing around in the ceiling, etc. If you can do that great. Joe Six-pack will likely find that intimidating. His options are to find someone to do that for him or just buy a wireless router for $50 - $100 and call it done.
...And currently, it's 2.4 GHz.
Before that, it was the 900 MHz band -- until it filled up with cordless crap.
As others have posted, 5 GHz is still pretty clean, so use it while you can. In our residential area, 2.4 GHz is full (even 14 is in use), but there's little activity on 5 GHz, so that's where our macbooks connect.
Same at work -- dual mode phones, bluetooth, microwave ovens, old laptops and more all on 2.4, with the newer equipment connecting on 5 GHz.
well you can drown out the other guy just watch it with after market antena's or you can go way over the leagal limits :-) about 78mw is aparently where the limit is on a wrt54g
Well, enterprise APs are.
I run a Cisco LWAPP (now CWAPP) system that auto adjusts channels and power levels. On the enterprise side the challenge isn't the AP technology, it's the fact that just about every gadget, and even to this day a lot of laptops, do not have a 5GHz radio/antenna. The customer saves pennies, then ends up competing for bandwidth.
Also I suspect most drivers are not smart enough to realize that a just-good-enough 5GHz signal should be held onto instead of leaping to a stronger, but crowded, 2.5GHz channel.
As of this moment at a modern university, 6 out of 7 clients are 2.5GHz -- and that's about the best I've ever seen it, actually.
Someone had to do it.
Leave all that trash on 2.4Ghz. I want to be able to continue to use 5.1,5.2 and (to a lesser degree, since phones use it too) 5.8. As soon as we get a proliferation of $25 devices on the 5Ghz spectrum, we'll fill those up too.
You can control the power level on Apple's Airport stations, but not automatically - you have to manually adjust a slider and (I think) reboot the router for it to take effect. It is possible to dial down the level though if you don't need the full strength, and you want to make your network tougher to connect with, or your neighbour is complaining that you are melting her brain with your evil microwave signals.
It's cheaper than buying her a tinfoil hat, but much less hilarious.
Parenthetically, I recently purchase a Bullet M and outdoor antenna from Ubiquiti, and wanting to avoid the whole 2.4GHz zoo, I bought the 5GHz version.
I actually did something similar when I bought my first wireless router five years back.
Wireless networking was just starting to really take off around that time and even then I was worried about potential congestion issues. Most devices being sold then were 2.4GHz 802.11g/b models, with 802.11a support being far less common.
Anyway, I bought a tri-format 802.11a/b/g laptop card and router precisely *because* 802.11a was far less popular and less likely to suffer congestion. Unfortunately, such devices were also more expensive- I assume because they needed dual radios- which is probably the reason 802.11a was never that popular in the first place!
Turned out that congestion was never a major issue in my situation, and my current laptop doesn't support 802.11a anyway. When was the last time you heard of 802.11a anyway?
But I'd still buy 802.11n equipment with 5GHz usage in mind, so long as the cost difference wasn't prohibitive. (One interesting question; can 802.11n devices support 802.11a in the same way that the 2.4GHz 802.11g devices supported 802.11b?)
"Slashdot - News and Chat Sites Deviant". (Click "homepage" link above for details).
The IEEE-802.15.4 specification defines a way to reduce power, but it does not enshrine this at the MAC layer of this protocol. Perhaps Zigbee may do this, but it isn't in '15.4 as far as I have read.
The feature you're talking about is called Clear Channel Assessment (CCA) and it is part of ,most of the wireless specifications. The problem with CCA is that the threshold is shockingly low. And what you hear at the transmitting end isn't necessarily what the receiver hears. In other words, the receiver could be trashed by another signal too far away for you to hear. I need to remind everyone here, this is not a coaxial cable or a fiber system. It is radio. Radios wave systems are not perfect hubs or trunk lines. There are signals on the air that one side may hear that the other doesn't.
Another issue you might not realize is that it takes at least as much power to run an 802.15.4 receiver as it does the transmitter. In most cases, the the transmitter is the local oscillator as well. There isn't much power to be saved.
So why reduce power? To reduce the chance that a signal can be received by others with nefarious intent, and to reduce interference as you said.
I suggest people consider using different channels. Even though the 802.11 channel passband is over 22 MHz wide, and there are really only three channels that don't overlap, you can still choose an adjacent channel and use the despreading to your advantage.
I find that the default channel for most of 802.11b/g routers is channel 6. Use anything but that and you'll probably do OK. Those who can remember the heyday of CB radio, may remember that most of the kiddie walkie talkies used to be on CB channel 14. That was the one channel you didn't want to be on. It is interesting that we still haven't learned that lesson even today.
Nearly fifty percent of all graduates come from the bottom half of the class!
OK, in the US, the 2400 to 2500 MHz band is allocated for use by Industrial, Scientific and Medical devices. In this band RF devices may emit signals provided those signals are low power and they do not interfere with licensed users. These devices are also required to accept interference from other ISM devices and from licensed users. The only reason WI-Fi works is the probability that there are few if any licensed users in your neighborhood. I suppose we should all be thankful that Wi-Fi works as well as it does.
Currently, the licensed users of the 2400 MHz band are:
Amateur radio; 2390-2450MHz
US goverment radio location; 2417-2450 MHz
Fixed communications services; 2450-2483.5 MHz
Mobile communications Service; 2450-2483.5 MHz
Radiolocation services; 2450-2483.5 MHz
Satelite communications; 2483.5-2500 MHz
As far as the 5GHz band goes, ISM is allocated 5.725-5.875 Ghz. This band is also subject to the same limitations regarding licensed users. In the 5GHz band the users are amateur radio, radio location, fixed and mobile communications and satelite communications. This band is also potentially full too.
Those of us who use Wi-Fi or 5GHz should be thankful there aren't more licensed users in our neighborhoods.
The problem is that access point manufacturers will always set their devices to FUCKING LOUD because all they care about is their own product's range and signal strength.
So what if their router stops the neighbours router working and makes your bluetooth mouse have a fit? At least their product looks good with it's 3 MIMO antennas and TurboBoost which uses all 11 channels and gets you a couple of extra signal bars at the other end of the house. Unfortunately most people won't even realise that interference and too high signal levels are what are making other equipment not work properly, especially if their neighbour is the one with the offending device. All they see is a shitty Bluetooth mouse that doesn't work or a crappy phone which doesn't sync.
In my house I can't use channel 1 for wifi. It just never works. There are no other APs around that frequency so I presume it must be some other device belonging to my neighbours. I have a feeling if I asked them to check if any of their wireless devices are polluting that part of the spectrum I'd probably just get a blank stare.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
It sure was entertaining to watch my FIL bitch about how I'd broken something on his laptop, because the Internet wasn't working...
While he was talking on his 2.4GHz phone.
With the microwave cooking his dinner.
No, no degree of explanation helps the matter. Most people are like this; they don't get the whole 'frequency' thing at all.
~/ssh slashdot.org ssh: connect to host slashdot.org port 22: too many beers
As you get to the end of the range noise is generally dominated by receiver noise, interference etc not by transmitter noise (which don't forget is attenuated as much as the signal)
So I would expect cranking up the power to increase range unless the transmitter gets so noisy that even a close-by receiver is having trouble.
Still use it wisely and watch out for the FCC ;)
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
In addition, you're cramming more wattage through the wireless IC's. If you don't take steps to mitigate this (heatsinks, even a fan perhaps) you _WILL_ burn out the router, sooner or later.
On WRT hardware, the wireless IC's are under the 'shield' and is not actually the Broadcom chip.
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
Well, not quite all of them. One of the main benefits with tinkering with DD-WRT on Linksys b/g hardware is being able to boost the output from the rather puny(but effective for most) factory 28mW to well over 200mW.
I hope you checked it on a spectrum analyzer to make sure that your out-of-band radiation was still within legal limits when you cranked up that setting. Over-driving an amplifier can create lots of unwanted harmonics and doesn't necessarily make the intended signal any stronger.
How about we impeach your face!?
For large sets, this will be our guide even unto death, for the LORD will work for each type of data it is applied to...
I hope I'm not being picky here... Routers are not Wireless Routers. I have a couple of Cisco routers and none of them give me WiFi access.
w00t
http://xkcd.com/474/
I thought that we should always ask if the frequency is in use before we called CQ.
FB OM de w7com
-- I have a private email server in my basement.
Too bad the above is just a pipe dream. I can't imagine how bad it is living in dense residential/apartments, where these users still don't know how to configure things, but there are 2 dozen within range instead of 5.
Except for that mess-up in the early days of N that would just obliterate everything in range, it's not as bad as you would think. You're lucky to get 20m range in this apartment complex, but the apartments aren't that big anyway. Similarly, being in America, the signal degredation brings the transmission rates down to... oh... about the paultry upstream we get from the cable provider anyway.
The ______ Agenda
That's correct; as I said, "I don't know of any protocol that does this." 15.4 does do CCA, and yes, it has the limitations you describe. The hidden terminal problem lives.
We arranged the 15.4 channels so that there would be one between each of the three non-overlapping 802.11 channels, plus a couple above Channel 11, figuring that if any portions of the spectrum were clear, those would be the spots.
The receiver power consumption in the first 15.4 receiver I designed (still being sold by a major IC house, despite being long in the tooth) was actually higher than that of the transmitter, due to a rather conservatively designed ADC. This was fixed, in a manner that can only be appreciated by a semiconductor marketing manager, by increasing the rated transmit power until the "right" relationship was attained.
Bonus points when she's calling from her cellphone to complain.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
They understand frequency only in a very limited way. Frequency is something you dial your radio to to switch the station. And they don't overlap, simply due to reglations, so they don't get the concept that such a thing could happen.
They especially don't grasp the idea that different kinds of devices could interfere with each other. One is a cellphone, one is a WiFi Router, how could they get into each other's way. And a microwave? That doesn't transmit any data, so how could it in ANY way interfere? I spent a good deal of time trying to explain it, and even when the interference could quite obviously be traced to the microwave (mw on - interference, mw off - all ok), it was argued away that it's just coincidence, that it has something to do with the power lines and that somehow that microwave using power had some "bad influence" on the router (which happened to be on a completely different circuit...) and so on. It could NOT be a frequency problem, no way!
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Manufacturers don't care about their product's signal strength either. Know what they care for? Returns.
That's also the reason why they ship their routers by default with any security disabled and an empty admin password, configurable via cable and wifi and as open as can be, just to make sure that it "works" out of the box and nobody could remotely be too stupid to get that box up and running.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
I believe the FCC allows 802.x devices 1mW/channel over ~15 channels. That's what all wireless cards are set to.
Manufacturers make there products to produce the best experience for the most people. Most people don't live in multi unit buildings. They live in the burbs where maybe one or two neighbors has WIFI. People want to connect to their AP in the den from their bedroom, maybe two rooms away. 5GHz doesn't penetrate walls/doors nearly as well as 2.4GHz (higher frequencies are more line of sight). 5GHz equipment won't interoperate with older WIFI equipment. It costs more to manufacture also (higher frequency components cost more).
A system with M antennas (.11n) can give roughly M times the throughput of a single-antenna system or can cancel roughly M-1 strong interferers. Even if it isn't here now, future systems will do a smart tradeoff between high throughput and interference cancellation, use spectrum sensing ('cognitive radio'), and add more spectrum to give very flexible systems.
1,5,9,13, just move to europe, everybody knows any map can be coloured in just 4 frequencies (1,5,8,11) wouldn't be too bad either, but generally just fireup aircrack and find a fairly empty spot, even when i lived in london it wasn't to hard to find one (the fact i could borrow the neighbours if i lost signal helped too (WEP, LOL it's like they wanted me to use it))
I'm guessing these people have never used a Nextel/iDEN phone? I don't think anyone could miss the interference on their speakers, especially with all the people who like to use their phone while driving...
I've had luck in this department too. All the neighbors have their routers set to, which basically translates to channel 1. So while they're overlapping like crazy, I've got about 10 channels to use that are free and clear.
And I don't have a microwave.:D
Deck, stupid Windows 7 handwriting recognition swallowed my word.
Meant to say that all the neighbors have their routers set on "Auto".
When I moved to where I am now, I had very intermittent wireless signal due to poor neighbouring configs. I pushed a short pamphlet through some local letterboxes regarding wireless channels and how to get maximum signal strength without crippling everyone elses connections after Netstumbler found 6 access points using channels 4 to 9 around me. I guess they were binned, as after a week nothing had changed.
After a week of channel-hopping with a borrowed +15dBi antenna, I had some folks come and ask me about proper wireless configs. Sometimes a mallet to the skull really is the only way to teach some people...
Finally had enough. Come see us over at https://soylentnews.org/
if a couple hundred channels were available instead of just 14 or so, i think it could work much better. that would veer off the 2.4ghz frequency i suppose, but it's the only way that i see. in fact if a whole bunch of stuff was moved onto frequency-hopping we could get more available frequency, and cleaner.
Build your own energy sources from scratch. http://otherpower.com/
Well, here's a question. How many people are going to use the software router functions? Honestly?
Apart from say some chap at an airport paying the fee to get access and then sharing it to his friends/coworkers/family members so they can get net access wiithout paying for it...who is going to use that feature all the time?
Take me for an example. I played with the software for all of 30 minutes. I got my Wii to share my laptop's 3G card and said "Wow! That's Spiffy!" and then turned it off and turned my Comcast connected hardware router back on.
Why would you need a software router unless you didn't have a hardware router in your house.
For that matter if you didn't have a hardware router and just happen to be able to get your mitts on a USB Wireless Adaptor for cheap...I could see you using the software...but then you're using no more or less of the 2.4GHz band than some chap WITH the hardware router.
So, Is it really the fault of the software, or is it a fault of the simple fact that everyone and their grandmother makes wireless devices on 2.4 instead of using the other bands?
-- Wiccan Army, 13th Airborne Division "We will not fly silently into the night"
I just left it with wep, though my devices aren't wpa compliant. after cracking wep a couple of times, i saw that any sufficiently good networking tech can do it, but it's not for really just any amateur. one needs to know where to get the tools, and how to implement and operate them. need to understand wifi fairly well, networking, linux, and cracking, besides being in the neighborhood by chance, or being motivated enough to hang around outside on the street cracking my wep. and so now i have the wep key of a few neighbors. so what? i have internet already, and i don't see any use in seeing their files or their email or their breaking the copyright laws. and even if i did want to do that, it would be quite a lot more work, time and expense. it's not just about what is technically doable, it's more about how much it is feasible or practical to be done.
Build your own energy sources from scratch. http://otherpower.com/
You get that with any TDMA protocol: DAMPS and GSM, too. Though not on GSM if you have a 3G voice connection, that's CDMA.
-Dave Haynie
Yeah, my old AT&T GSM (non 3G) phone would not only drive speakers crazy, but also my CRT monitor when it was close enough. I've never directly observed interference from a CDMA phone.
- Me getting massive bandwidth gains trough being able to transmit trough all those forwarding routers.
- You losing all your bandwidth.
- Me making evil plans and stroking my white cat with my iron glove, while laughing maniacally.
Any sufficiently advanced intelligence is indistinguishable from stupidity.
About a 3rd of our wireless clients at any given time are 5Ghz devices, at about 2 to 1 .11n vs, .11a.
You need a wifi jammer.
Not every place builds houses from wood and paper. Over here they are made of steel reinforced concrete and I'm lucky if I get better than "Very low" signal strength between 2 places 10 meters apart within one flat. On the other hand it can be the crappy WiFi router supplied by my ISP.