802.11ac - New Era

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802.11ac, the emerging standard from the IEEE, is like the movie The Godfather Part II. It takes something great and makes it even better. 802.11ac is a faster and more scalable version of 802.11n. It couples the freedom of wireless with the capabilities of Gigabit Ethernet.
Wireless LAN sites will see significant improvements in the number of clients supported by an access point (AP), a better experience for each client, and more available bandwidth for a higher number of parallel video streams. Even when the network is not fully loaded, users see a benefit: their file downloads and email sync happen at low‑lag gigabit speeds. Also, device battery life is extended, since the device’s Wi-Fi interface can wake up, exchange data with its AP, and then revert to dozing that much more quickly.
802.11ac achieves its raw speed increase by pushing on three different dimensions:
●   More channel bonding, increased from a maximum of 40 MHz with 802.11n up to 80 or even 160 MHz (for speed increases of 117 or 333 percent, respectively).
●   Denser modulation, now using 256 quadrature amplitude modulation (QAM), up from 64QAM in 802.11n (for a 33 percent speed burst at shorter, yet still usable, ranges).
●   More multiple input, multiple output (MIMO). Whereas 802.11n stopped at four spatial streams, 802.11ac goes all the way to eight (for another 100 percent speed increase).

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