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Wi-Fi Gets Multi-Gigabit, Multi-User Boost With Upgrades To 802.11ac (arstechnica.com)
The Wi-Fi Alliance has announced its certification program for IEEE 802.11ac Wave 2, a technology that has been around on the market for more than a year. Wave 2 can deliver up to 6.8Gbps and lets an access point interact with more than one device at a time. Wave 2 features MIMO (or MU-MIMO) which improves the MIMO technology that lets Wi-FI transmit over more than one stream through the air. Wave 2 standard utilizes channels up to 160MHz wide (up from 80MHz channels available with Wave 1). It also creates more spatial streams and uses spectrum more efficiently, the industry group said on Wednesday. Ars Technica adds:On top of MU-MIMO, wider channels, and more streams, the Wi-Fi Alliance says Wave 2 features now being certified bring "support for a greater number of available channels in 5GHz," a change that "makes more efficient use of available spectrum and reduces interference and congestion by minimizing the number of networks operating on overlapping channels." You may have already noticed routers supporting some of these features, since the specification details have been available for a few years. In fact, routers with MU-MIMO started appearing in July 2014, and you can find routers that use 160MHz channels. The certification program takes a while to catch up with real-world implementations, but it ensures compatibility between devices and may spur faster adoption by vendors. End-user devices such as phones, tablets, and laptops must also be updated to take advantage of new features such as MU-MIMO.
I am now going to spend the rest of the day muttering moo-mimo under my breath....
My eyes reflect the stars and a smile lights up my face.
Meh, if you live in an urban setting the 50 assholes who live within wifi range and use a 40MHz channel width because they don't know what they are doing you'll get shit speed and connection anyway due to the interference.
That is true on 2.4GHz. AC uses 5GHz. More channels, less people.
Be or ben't
Actually if the standard garden hose in the US of 5/8" diameter represented 1.5Mb, assuming an equal rate of flow, I believe the 6.8Gb in 802.11ac Wave 2 would be represented by a pipe 60" in diameter.
Fewer people. Less range (which is one reason there are fewer people in range). Still better: Gigabit-Ethernet.
i use 60MHz you insensitive clod
Thanks for the reminder that I screwed myself by getting an integrated cable modem/802.11ac router. Meaning the router is controlled by Comcast. Meaning the firmware cannot be upgraded. Ever.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
The Nyquist limit only applies to amplitude encoding. Higher bitrates can be achieved by encoding information via attributes like phase as well, which should get you up to 16 times the bit rate. Not sure what the actual bandwidth of a WiFi channel is, there may be some overlap between adjacent channels.
I've abandoned my search for truth; now I'm just looking for some useful delusions.
It's about to be true for 5GHz as well, with Wave 2. The "Extended 5 GHz channel support" feature they are touting is carefully worded to whitewash the fact that 160MHz channels ruin channel plans by reducing the number of available non-interfering channels down to (with new FCC regulations) 4, only one more than 2.5GHz. Of course, nobody will be bonding 320G channel groups, so at least there won't be that part of the problem, and the additional channels are certainly welcome for 80MHz purposes, bringing the number up from 5 to 9. And 4 channels is certainly topologically much more than 33% better than 3 channels. It is a big relief that wave 2 didn't have to roll in on a 2 channel plan.
Wave 1 did indeed encourage device makers to actually put the 5GHz antennas back in, and wave 2 certification would encourage them not to leave any channels out (a.k.a. the "crummy hardware is why you cannot use 144 in a BYOD channel plan even though most systems support it" problem) and you don't *have* to turn on 80MHz, so there is some benefit to wave 2. Just, the hazard that prosumer equipment will come configured out of the box to run 160 puts us in a 4 channel universe when you don't have the authority to control spectrum use in a premises. Fortunately the standard also has some better avoidance/graceful-downgrade paths, whose full functionality I certainly hope are *required* for certification.
Someone had to do it.
Is this the kind of thing where most wave 1 devices can be software upgraded to wave 2 devices? Or is it yet another case of tossing out the silicon?
I would guess the glowing vendor support for this on one of TFS links would lead me to believe this will require new hardware.
From an AP support perspective, it really is annoying to have so many active fucking client standards to support. All the gee-whiz latest features are marginal benefits when half the spectrum is used by brain damaged clients vomiting all over the spectrum using old standards.
Well, that was a nice, easy solution, now wasn't it? I'm so glad you were able to come up with such a simple and obvious fix!
www.wavefront-av.com
True, but keep in mind that what matters is not just bandwidth, but bandwidth*time. If you have 100Mhz of spectrum to use, and user A and user B each get 50Mhz, let's say this gives them each 50mb/s of bandwidth. But if we let them both use all 100Mhz, then they each get 100mb/s peak bandwidth, while still having ~50mb/s each if it's congested. So if each of them has a fixed amount of data that they want to transfer, they use the same bandwidth*time as before. It only becomes a problem if you have a bandwidth hog who will use any available bandwidth you give them.
You mean to tell me that all the Ethernet cable I just finished running through my house is pointless.
Dammit!
That's wrong. I came up with 233 degrees Kelvin. That works out to around 3.2 acres for you metric people, and 85.67 Euros for the USA.
There were LANs before there was even internet access! Companies pay big money to upgrade their LANs (and WiLANs) even as their internet speeds don't increase.
If you've really got no use for it, no problem. Why you feel the need to announce it to a group of strangers is beyond my comprehension, but nevermind that. I can see millions of uses for it, even with slow internet speeds.
For the average person, you'll probably also see much better speeds when you're out on the fringe of the signal area, than you would with slower implementations, making it usable a greater distance from the router.
Plenty of people have DVRs, movie libraries, HDHomeRuns, and similar, where higher speeds would greatly help them view movies on their phones/tablets/rokus/etc.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
There is some benefit to contention issues from packets taking a smaller time. However, peak bandwidth is mostly worthless (as well as rarely achieved in RF) when put shoulder to shoulder with latency and packet loss. Which is why 11ac has fallback provisions for reducing the bandwidth, cutting slices out of channels to deal with interference. When you have a residential area where spectrum is not planned, or not enough staff/money to throw at really tuning things, contention mechanisms won't always work due to hidden nodes/APs Really the "160Mbps" is mostly a selling point for PHBs. Personally if they can get away with it, I can totally see network admins only turning on 160MHz channels near the CIO's office and the meeting rooms were they go the most, There are plenty of nice features in wave 2 which make it desireable to have (in about 5-10 years depending on the age of your client mix), 160MHz channels are not one of them.
Someone had to do it.
It does if the pressure is sufficiently low.
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