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802.11ac 'Gigabit Wi-Fi' Starts To Show Potential, Limits
alphadogg writes "Vendor tests and very early 802.11ac customers provide a reality check on 'gigabit Wi-Fi' but also confirm much of its promise. Vendors have been testing their 11ac products for months, yielding data that show how 11ac performs and what variables can affect performance. Some of the tests are under ideal laboratory-style conditions; others involve actual or simulated production networks. Among the results: consistent 400M to 800Mbps throughput for 11ac clients in best-case situations, higher throughput as range increases compared to 11n, more clients serviced by each access point, and a boost in performance for existing 11n clients."
The anonymous coward version of wi-fi.
Not bad though.
"Among (sic) the results: consistent 400M (sic) to 800Mbps throughput for 11ac clients in best-case situations"
Best case being: the only device on the network; inside a Faraday cage; on the dark side of the Moon; 3 centimetres away from the antenna.
BTW: Google.... fuck your dictionary. It IS centimetres.
When I switched from g to n (same router, same clients, just activated n mode), pings doubled, signal strength dropped by 10% and while the bandwidth is higher, so is the amount of random disconnects.
At 2 meter distance to the AP.
How's ac performing in that regard?
With 20+ APs contending for their own slice of half or third of 5 ghz band. 802.11ac took the best feature of the 5 Ghz band, plenty of non overlapping channels, then turned into back into the quagmire of the 2.4 Ghz band by allowing 80 and 160 Mhz spectrum usage. Of course, the router manufacturers are going to enable 160 Mhz by default even when everyone in the neighborhood is on a 25 Mbps cable modem connection.
someone like me with a 400kbps up/down Internet connection - wowsers!
Linux driver support for most of the 802.11ac devices are still iffy which doesn't help.
Hardware manufacturers I'm pointing my my finger at you. The most powerful features of 802.11n are largely unimplemented. Laptop/tablet/phone Support for 3 spatial streams is about as rare and rocking horse shit. Support for even 5 ghz is spotty at best and its hard to find out if whatever piece of hardware you want to consider buying even supports it. Heck even 2 spatial streams at 2 ghz is something your lucky to get unless you spend more than $699 on a laptop. The lowest common denominator for 802.11n and what the "wireless n" wifi support really means for half the devices on the market is a single spatial stream 802.11n at 2 ghz, which is 65 Mbps max. I can buy a mid range smartphone with 4g support and the wifi is still single spatial stream at 2 ghz. Hardware manufacturers have no incentive to put better implementations of 802.11n in their because most customers aren't savvy enough to tell the difference and demand better from device manufacturers. 802.11n is on old specification. There's no excuse why 2 spatial streams can't be the minimum. The silicon to do this is cheap and has been refined for many years.
802.11ac will probably suffer the same fate. The minimum implementation to get the "wireless ac" sticker on the box is going to be what half to three quarters of the devices on the market will support, even 10 years from now.
Have they implemented the full 256QAM 5/6 rate yet with full 80+80MHZ bonding yet? (160 MHZ of channel bandwidth) using 8 transmit antennas and 8 receive antennas on both AP and wireless clients?
I expect early APs and early chipsets will not yet fully implement all the advantageous features 802.1AC has to offer
They'll have made compromises to save money.
Seems I can't use speed as an argument for wired ethernet any more, as I'm not getting consistently over 60 MB/s with wired anyway, for file transfers. Technology is finally catching up, or alternatively, wired technology and OS-level file transfer efficiency have stagnated for long enough.
Some possible caveats, why wired may still be good: 1) Does this include client-to-client transfers, or are those half the speed? 2) Is there any directionality such that multiple clients can use more than the corresponding fraction of the badnwidth 3) what is the range...?
> The noise floor across the whole of the RF spectrum is rising by an average of 1db a year.
You are correct, but not for the reasons you discussed. If the millions of Transmitters were clean and well designed, they would not cause RF interference to other users (except where they were sharing common frequencies).
The problem is that much of the electronics junk generate spurious harmonics. Plasma TV's, PC's, BPL, etc. all put out a horrendous range of broadband rubbish.
This is compounded by many manufacturers and importers ignoring the existing EMC standards, as well as the corrupt regulatory bodies (FCC etc) turning a blind eye to the cheap plastic junk being imported.
Just one specific example. Once upon a time, manufactures used linear-mode power supplies with large transformers. In an effort to reduce costs, they have universally changed to using switch-mode supplies. These supplies are certainly cheaper, but they almost always generate much higher levels of radio interference.
There's a trade-off: Being able to buy cheap electronics means that there's a good chance you will be unable to enjoy it due to the resulting interference levels.
and yet ironically in my flat in Oxford earlier this year I couldn't get 802.11abcgn to work through the bloody thick walls!
Cue the 5m ethernet cable my brother lent me and I strung it across the flat (from filerserver to desktop you see)
I'm getting 7-9 MB/sec with my 802.11ac adapter, whether on the 2.4GHz band or the 5GHz band. So at least the theoretical speed of wireless G is finally real.
It is much faster than the 2.5MB/sec I was getting on the so-called "a/b/g/n" adapter.
For comparison, on actual gigabit ethernet, I get about 88-100MB/sec.
I want to be able to pull into any McDonalds parking lot and always have my laptop get a solid lock on the Wi-Fi -- as opposed to the current situation, which is rather hit-or-miss.
No number for worst case latency - Something needed so VoIP actually works.
I suppose it is not very good or they would have mentioned it.
My summery of the technology would be.
Got a bleeding edge MB last month, included ac wifi. Looked into buying an ac router. Not that many actually available, and the few that were cost 150-250$.
I will stick with my g router which probably is worth about 10$.
I will wait until they become a bit more affordable.