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IT Shops Coping With Overloaded 2.4GHz WiFi Band
alphadogg writes "Of the 470,000 Wi-Fi connections made on a recent day at Abilene Christian University, fully 94% used the 2.4GHz band, representing an extreme example of how today's surging number of Wi-Fi clients is crowding the band least able to accommodate them. At ACU, this is not considered a problem, at least not yet. In part, that's because of careful wireless LAN design and capacity planning. And partly because a goodly percentage of mobile devices that can run on the alternative 5GHz band, do so: on that same day, 47% of the school's laptops and desktops, and two-thirds of its iPads cruised on 5GHz, via either 802.11a or 802.11n. Yet relatively few of today's Wi-Fi clients support 5GHz."
94% used the 2.4GHz band
... cruised on 5GHz,
47%
I attend a state funded technical college in Kentucky. We just had a technology audit/overhaul done over the summer break. Before summer, I could always connect to the wireless without a hitch. Sure it was a little slow, but it worked. After we cane back from the summer, I can't even get my wifi to associate with the router. Turns out, they redid the subnet ting and only allow 255 ip addresses to be leased at a time. 255 ip addresses. On a school network. Where everyone has a laptop and a smartphone. What the hell? I talked to the it guys and they said they're waiting to hear from the ISP so the can raise the number of leased up addresses. That doesn't make a whole lot of sense. Someone explain that one to me?
I find it largely annoying that "Wireless N" doesn't imply support for 5GHz. Many "Wireless N" devices only support 2.4GHz and most are bad at labeling whether they support 5GHz or not. It makes it difficult if you're looking for devices that support 5GHz "Wireless N".
From a cost perspective, I understand why they might only support 2.4GHz. I just wish they called it something else, like "Wireless NS" or something.
No, hes not doing it wrong. 5 GHz is shit for anything but open-air.
Look at the number of smartphones, e-readers, laptops and Android tablets out there that don't support 5 GHz. With the premium price of some of these gadgets I'm surprised vendors are trying to shave expenses by getting 2.4 GHz-only 802.11n chipsets.
If you get an opportunity, let the vendor or salesman know you one of the features you look for is 5 GHz capability. Make a point of it.
Learning HOW to think is more important than learning WHAT to think.
Anyone knowledgeable about the conflict is 2.5GHZ that led the US FCC to limit wifi from using channel 14 (2.484 GHz)?
According to the FCC spectrum chart the top of the 2.4 wifi band abuts the "Standard Frequency and Time Signal" Band at 2.5 GHz. What is that used for?
The 2.4Ghz problems will evolve the same way on the 5Ghz band
Not really. 2.4G has 3 bands. 5G has, depending on the country has 4 to 8 times as many. Make that 2 to 4 when you turn on dual channel bonding, and then you are talking worst case 6 channels. That means that you can tesslate the 5G band much closer together, without APs that are on the same channel getting as close to each other (and no, dropping Tx power isn't a perfect solution to that problem on the 2.5G band.)
So it's much easier to microcell on the 5G frequencies, in fact AP density can be cranked up absurdly high.
Someone had to do it.
...but for some reason my house chooses to be the exception to the rule. I've always had trouble getting 2.4GHz to reach to certain portions of the house, but when I added 5GHz (Apple Airport Extreme) I can now easily get a signal from anywhere in the house and even outside...
There's the phenomenon...
...I can see 5-6 (check that, right now it's 9!) neighbors' APs on 2.4GHz, but so far I'm the only one on 5...
...and there, I'd say, is your explanation for it.
MCSE? No, sir...I don't do Windows. Yes, I am an idealist. What's your point?
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Look for 802.11a support. It requires the 5 GHz band.
The main problem is that 802.11A/N is totally the wrong kind of protocol for crowded environments where you have lots of individual users who need reliable and robust connectivity that doesn't necessarily have to be individually fast. 802.11N in particular was optimized for the questionable use case of making your neighbors hate you so you can avoid running cat5 between your living room and den, instead of enabling lots of adjacent users to peacefully coexist. Hand-offs are still kludgy, and it's rare to find someone who doesn't do wireless networking for a living who can literally walk from the back yard down to the basement and upstairs, then out to the front yard without having his connectivity break (and break *hard*) at some point along the trip.
What do I propose? "802.11u" (as in, "UMTS"), running on unlicensed 5.8GHz. Stick private picocells in every room, hallway, and area. Multiple ones, in large areas. Wire them together with ethernet, or optionally create a peer to peer mesh network for the backhaul (5.8GHz where good links are possible, 2.4GHz for links between floors or "difficult" walls). Then take more or less canonical UMTS, and implement it as micro cell sites in devices with the approximate form factor of a smoke detector.
The nice thing about UMTS is that it's CDMA, just like 1xRTT (and ironically, unlike EVDO). You don't have to do local spectrum planning. If an area has poor throughput, just buy and add more femtocells or picocells to the congested area, let the devices negotiate lower power levels, and watch CDMA work its magic. By linking the PicoFemto/cells together, they'll magically work the same way a real cellular network does (sharing their bitstreams, and allowing them to reinforce each other and cancel out local/directional noise).
5.8GHz private UMTS wouldn't be fast (it would probably max out around 2.5mbit/sec at the cheap end, and max out around 10 or 20mbit/sec for a high-end corporate network where cost was no object), but it would be perfect for places like college campuses, offices, etc. where you have lots of people who need mainly internet access, but no single user necessarily needs GIGANTIC amounts of individual bandwidth. In other words, the exact places that are a total clusterfuck mess today, because you have hundreds or thousands of users stomping all over each other trying to use a wireless protocol optimized for streaming HD media from a point source to a single hungry consumer.
It might even be possible to make a cheaper "home" version that ran with uplink & downlink sprayed across the entire existing 2.4GHz wifi band -- the idea being that if Qualcomm has a chip designed to do 1900 & 2150MHz uplink/downlink UMTS, extending it to add ~2.4-2.5GHz would probably just be a straightforward next-gen upgrade that would be easy to add to any Android phone (or iPhone) that already had UMTS capabilities.
I have no idea whether this could possibly be cheap enough to justify doing at home, but I suspect the costs would be fairly competitive to what businesses, colleges, and hotels spend kludging around with high-end enterprise WiFi *anyway* today.
WiFi cabled to switch-router, how about they get a better network designer.
If that many WiFi spots are cabled to the same nodal switch, then that is just one problem of many.
Has any one tried a flood-ping at any one of the WiFi spots, I suspect, it would be an avoidable single/few point DOS attack with a good network design.
Unaccountable leaders are masters, and unrepresented people are slaves. How do US and EU fare?