A standard in the making
802.11ad, although not a final standard, is on its way to becoming one at the IEEE (Institute of Electrical and Electronics Engineers), which for decades has hammered out new network technologies. By using the abundance of uncluttered spectrum in the high-frequency 60GHz range, 802.11ad will be able to transmit data much faster than today's 802.11n technology that uses 2.4GHz and 5GHz.
It wasn't easy getting to today's wireless networking technology, though. With 802.11g, Broadcom dominated the market for chips, Grodzinsky said, a situation that didn't please competitors. Its sequel, 802.11n, was bogged down as those competitors jockeyed over the standard, which took seven years to complete.
"This time, we learned from 11g and 11n," he said, and backers such as Broadcom, Qualcomm Atheros, Intel, Microsoft, Marvel, Cisco, Samsung and Wilocity have joined a consortium called the WiGig Alliance to cooperate. Now IEEE is working on the standard and has made more progress at this point on 802.11ad than it had at this stage of 802.11n's lifetime.
802.11ad also piggybacks on existing efforts such as the Wi-Fi Alliance's Wi-Fi Direct technology, which lets 802.11 devices--say, a camera and a smartphone--connect without relying on a home network.
How fast is it?
The technology is designed to reach speeds of 7 gigabits per second, though Wilocity's first chips reach just 4Gbps. That compares to a theoretical 802.11n maximum of 600Mbps, but in practice even high-end 802.11n consumer products only reach half of that.
The 802.11ad technology uses directional communications. Instead of bathing a room or a house in a wireless signal, 802.11ad technology sets up specific channels between devices' antennas. That minimizes interference.
Grodzinsky also argues that 802.11ad will have power consumption advantages. Unlike with 802.11n, for example, dialing down the 802.11ad data transfer speed by half will cut power consumption by more than half.
But there's no free lunch: 802.11ad works only over short distances. For practical purposes, that means within a room.
That distance limitation means 802.11ad is a lousy replacement for existing standards such as 802.11g, 802.11n, and the forthcoming 802.11ac, all of which can generally reach throughout a house. But that doesn't mean that 802.11ad is useless.
What's it good for?
There are two ways that Wilocity and its allies in the WiGig Alliance developing 802.11ad hope the technology will be useful.
First, 802.11ad will be paired with lower-frequency wireless networks, so devices that are close together can use the high-speed connections, Grodzinsky said, and devices can switch from one to the other behind the scenes without interrupting people's network use.
That's pretty important, since it offers a speed boost in some cases but a safe fallback otherwise. In other words, this scenario extends existing wireless network technology; customers paying a premium over 802.11n devices would be betting on its utility but not replacing more conventional wireless networking.
"We're not saying 60GHz will replace the home network. You'll still have 802.11n for the home network. 60GHz will be in-room or adjacent-room technology," Grodzinsky said. In Wilocity's case the 802.11n link is provided through a partnership with Qualcomm Atheros technology; Grodzinsky sees a natural evolution to 802.11ac as that technology matures as an 802.11ad partner.
Second--and this is the more dramatic idea when it comes to its utility--802.11ad adherents hope the technology will rid the world of some cables. Wilocity's data-transfer 4Gbps speeds is fast enough to transmit video and has low enough communication delays that it can be used for interactive tasks.
So, for example, a business traveler could bring his laptop back into the office and start using it with a large monitor, an external keyboard, and a mouse. Or a student could bring her laptop back to the dorm and it would automatically start backing up her data to a local hard drive. A tablet could transform into a device with a physical keyboard and mouse--and rapidly sync new video, photos, and music with a PC with no cable.
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