The Future of 802.11ac

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Posted by timothy on Sunday December 30, 2012 @10:12PM from the always-a-game-of-catch-up dept.

CowboyRobot writes "The 802.11ac standard is expected to be ratified in 2013 and NetworkComputing has an interview with representatives of Cisco Systems and Aerohive Networks about what that will mean for everyone else. 'Out of the gate, the increases in performance over 11n will not be tremendously impressive. The second wave--which will require a hardware refresh--gets far more interesting... First-generation 802.11ac products will achieve up to 1.3 Gbps through the use of three spatial streams, 80-MHz-wide channels (double the largest 40 MHz channel width with 802.11n), and use of better hardware components that allow higher levels of modulation and encoding (up to 256-QAM). Whether we will actually see 802.11ac products capable of 6.9 Gbps is dependent on hardware enhancements on both the access point and client that are not certain.'"

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Re:I'm a wire guy by Ultra64 · 2012-12-30 22:35 · Score: 2

"I haven't seen more than low single digit MB/s over wireless LAN, even under line of sight conditions with hardly any interference."
You must be using shitty hardware. We're using ubiquiti hardware at my office and getting the expected speeds.
Not sure the big deal here... by RLU486983 · 2012-12-30 22:36 · Score: 2

damned ISP's choke the shit out of our connections so what is the purpose for exactly... killer LAN parties?!?
1. Re:Not sure the big deal here... by vlm · 2012-12-31 00:31 · Score: 3, Insightful
  
  My somewhat extensive experience with mythtv and wireless is that you need speed to work around latency due to interference or random multipath or whatever it is that occasionally slows stuff down. If you've got 1000 mb to transfer over 1000 seconds then on average you only need average speed X. However if you need to transfer exactly 1 mb every second, or the picture breaks up, and you occasionally endure 9/10ths of a second interference/outages, then you need 10 times the average speed to deliver. Or a bigger buffer, which means a long spooling up delay.
  A good IT analogy is its like the difference between batch processing and a realtime OS.
  Or maybe a standard /. car analogy is something like if you've got a 200 mile range gas tank, it doesn't really matter where the gas station is as long as its less than 200 miles away when you have a full tank... but the instant that the closest open gas station is 201 miles away, you're all done. Maybe thats an awful analogy...
  No wait I've got a better car analogy. My gas station can deliver something like 5 gallons per minute, which seems like gross overkill for my fuel injectors which barely burn 2 gallons per hour on the highway. However the key point is my fuel injectors do NOT use 2 gallons per hour, they really use a microscopic droplet 60 times per second. Or something like that. Too early in the morning...
  
  --
  "Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Congestion & old nets = little benefit by phayes · 2012-12-30 22:38 · Score: 5, Insightful

802.11ac isn't out yet but I have little hope of it really helping. I live in an apartment building I can already see 50+ routers on 2.4 & 10+ ON 5GH.
I just don't see that much of a benefit unless the congestion avoidance is really better than 102.11n.

--
Democracy is a sheep and two wolves deciding what to have for lunch. Freedom is a well armed sheep contesting the issue
1. Re:Congestion & old nets = little benefit by AmiMoJo · 2012-12-30 23:17 · Score: 2
  
  If you transmit at higher speed it takes less time to send a given volume of data, allowing everyone else more time for theirs. Compared to 802.11n which will use 50%+ of the available bandwidth for streaming HD video the new AC standard might only need 10%.
  Of course all that is mitigated by a single 802.11g router being maxed out by someone doing a download.
  
  --
  const int one = 65536; (Silvermoon, Texture.cs)
  SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
Re:I'm a wire guy by TuringCheck · 2012-12-30 22:41 · Score: 3, Insightful

I've had just over 200 Mbit/s with 5 GHz 802.11n, sitting in the next room from the AP, with a wall between us.
And probably noone else using the 5 GHz band in your area - am I right? Because as soon as the signal / noise ratio decreases the high efficiency modulations stop working and you must live with much lower spectral effifciency - that is' much lower usable bandwidth for the same slice of the spectrum.
Unfortunately increasing the transmission power doesn't help a lot - after all, the neighbour wants high bandwidth as well leading to an arms race.
Re:ho hum. still waiting by TuringCheck · 2012-12-30 22:44 · Score: 2

for 802.11y hardware
The real speed will arrive with 802.11xxx - specially designed for broadcasting 3D porn ;-)
Re:I'm a wire guy by neokushan · 2012-12-30 22:54 · Score: 5, Interesting

Remember that 5Ghz has a much shorter range than 2.4Ghz so the problems with traffic congestion won't be as bad. If all of your neighbours switched to 5Ghz, you'd still see a noticeable real-world improvement over 2.4Ghz.

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+1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
Realism... by solidraven · 2012-12-30 23:22 · Score: 2

256-QAM modulation for wireless data transfer, sure...
What's the intended range in realistic situations, 5cm?
1. Re:Realism... by Luckyo · 2012-12-31 00:19 · Score: 4, Informative
  
  Shorter range is a significant advantage today because it reduces interference.
  Interference is probably the main reason for lack of speed and reliability in modern city apartment WiFi.
2. Re:Realism... by brunes69 · 2012-12-31 00:28 · Score: 3, Interesting
  
  And when you live in a house, like oh say 50%+ of the population, you will now have to purchase 3 wireless routers to ensure coverage, whereas previously only one decent one was enough.
crypto by spikestabber · 2012-12-31 00:09 · Score: 2

With all the recent Wi-Fi developments, why isn't encryption now standard? I should be able to setup an *open* access point with encryption these days so my users don't get their email passwords jacked. There is absolutely NO technical reason why this cannot be part of any modern specification. I will never ever use an open access point for this very reason...
1. Re:crypto by drinkypoo · 2012-12-31 02:12 · Score: 2
  
  I should be able to setup an *open* access point with encryption these days so my users don't get their email passwords jacked. There is absolutely NO technical reason why this cannot be part of any modern specification. I will never ever use an open access point for this very reason...
  Security: you don't understand it, so you're doing it wrong. Your problem is that you're too trusting. You don't trust sniffers, sure, but you trust the router you're connecting to, which is beyond daft. You should never trust some random jerkoff's AP. They could well be subjecting all of your packets to DPI to look for passwords after they are decrypted by the AP. Or you could use https or ipsec and then the data remains encrypted until it arrives at the intended destination, which is how you actually protect your data.
  
  --
  "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Re:Hoping for indoor range improvements by jones_supa · 2012-12-31 00:14 · Score: 2

Is it possible to simply deploy more APs?
Re:Hoping for indoor range improvements by Luckyo · 2012-12-31 00:18 · Score: 2

None. Most of them are about reducing congestion problems, typically through reducing range (like 2.4GHz to 5GHz shift) or various antennae and beamforming solutions.
Your problem is the exact opposite, and typically handled by installing additional WiFi routers or amplifiers. Your problem has been long solved, but it would appear that your motel is simply not interested in investing in solutions.
Re:I'm a wire guy by hairyfeet · 2012-12-31 01:06 · Score: 2

Bimbo Newton Crosby, it all comes down to the neighbors. in areas where nobody else is running .N hardware? I've been able to get speeds for my customers on their wireless networks that were as fast as the cable could go, whereas in places where multiple people are using? They are lucky to get 200k in some places.
The problem is just too damned many people are jumping on the wireless bandwagon and even the ISPs have started handing out wireless routers (at least in my area) so the whole thing is just too crowded. I would say we need another channel but considering how much wireless spectrum goes for good luck with that, I'm shocked some company hasn't bought from the government one of the channels we already have.

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ACs don't waste your time replying, your posts are never seen by me.
Re:The law by markdavis · 2012-12-31 01:59 · Score: 2

I know it would require more bands... and that is precisely what is needed. What is taking so long? The FCC auctioned off billions of dollars worth of bands to companies for mobile phones/etc, and we citizens are still stuck with these few crappy little crumbs for one of our most important wireless technologies.