Wednesday, October 27, 2010

Wi-Fi Direct Certification Starts

Five chipmakers have certified Wi-Fi Direct reference designs: Wi-Fi Direct is a terrific addition to wireless networking where a device that offers a service can broadcast that service's availability, like printing or file exchange or what have you. It's a form of peer-to-peer networking that doesn't require an access point to intermediate, and is ideal for mobile devices, and devices that lack much of an interface. The first five reference designs have been certified a few months later than the original rough target announced last year. (See "Wi-Fi Alliance Peers into the Future with Ad Hoc Replacement," 13 October 2009.)

Wi-Fi Direct has a few things in common with newer Bluetooth devices that pair with less effort than in the original Bluetooth schema, and in that Bluetooth and Wi-Fi Direct both advertise available services. But the notion is that you get the speed (up to 802.11n) and security (WPA2 mandatory) of Wi-Fi with enormously simpler setup than connecting to a new Wi-Fi network for a moment and then setting up a connection with a specific device. And in cases in which you don't have an access point, such as trying to exchange a file between two mobile devices, it's extremely irritating. (On an iOS device, both parties could have a package like GoodReader that has built in WebDAV client and server software with Bonjour discovery, but you still need an access point to which both devices are connected, and security is an overlay.)

This announcement went around the world like a shot, but was typically covered incorrectly or incompletely in four ways. First, this is nothing new. The spec was announced a year ago; this is the culmination in silicon of that effort. It's great to see this implemented, because now we can move forward to have devices that support it.

Second, it's not yet available. The five certified devices are reference designs that other companies (OEMs or original equipment manufacturers), like Linksys, D-Link, Dell, Acer, and the like will build into products or relabel to sell under their own names. That means there's still some time to the market.

Third, this is host-side stuff—things to make a computer act as a Wi-Fi Direct enabler. It's not the technology needed for embedded client-side support in, say, an HP multi-function printer.

Fourth, there is no announced operating system support yet, even though Microsoft and Apple sit no the Wi-Fi Alliance board. That is not unusual for newly released hardware implementations of standards from the Wi-Fi Alliance or other groups. Apple and Microsoft both have near-term releases of operating systems upgrades on the timeline (Mac OS X 10.7 and Windows 8). It's most likely Wi-Fi Direct would appear in a new system, and might not be available in an older device.

Finally, and this wasn't addressed in any of the coverage I saw, you're going to need to see widespread adoption in mobile operating system platforms to make Wi-Fi Direct truly useful, and integration at a fundamental level of the OS. That means Android, BlackBerry, iOS, Palm WebOS, and Symbian (whichever version), as well as featurephone platforms from Nokia and others.

The reason is that mobile OS's, even the supposedly open Android platform, need to put Wi-Fi Direct hooks down into the driver level so that third-party developers can hook into a system-wide printing library that works with Wi-Fi Direct, or file-transfer support within apps.

Wi-Fi Direct is terrific, and I will be glad when it's widely available, But my prediction is that it won't have widespread impact until 2012. On the Wi-Fi timeline, that's perfectly fine. Each 802.11 standard as certified by the Wi-Fi Alliance has taken 2 to 4 years to percolate into the market. WPA2, rolled in 2004, is just now becoming the de facto security method, for instance. Wi-Fi Direct's greatest impact is on the future, not the present.



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