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New Wi-Fi Brand Emerges: Wi-Fi Direct

The Wi-Fi Alliance, an industry trade group for the promotion of all things Wi-Fi, announced recently that a branded version of new wireless peer–to–peer networking protocols are in the pipeline. Dubbed Wi-Fi Direct, “The Wi-Fi Alliance expects to begin certification for this new specification in mid-2010, and products which achieve the certification will be designated Wi-Fi CERTIFIED™ Wi-Fi Direct…Only Wi-Fi Alliance member companies will be able to certify devices to the new specification.”

The 802.11 standard already supports peer-to-peer mode for creating ad hoc mesh networks, referred to as an Independent Basic Service Set (IBSS), where any device that starts a mesh network chooses the network ID, the SSID or Service Set Identifier. As is currently the case, not having a Wi-Fi Alliance badge doesn’t preclude interoperability with certified devices; it just means that a particular product may not work with certified peers.

Wi-Fi Direct is an extension of the existing 802.11 specification that will allow certified products to connect, even without a Wi-Fi network. Its peer-to-peer technology will enable users to connect Wi-Fi Direct devices to each other anywhere, with or without a Wi-Fi network, hotspot, or Internet connection.

In addition, two or more compliant devices will be able to easily connect, enabling applications such as printing directly from a camera, sharing and syncing music and contacts directly with a friend, and displaying pictures directly from a mobile phone onto a TV.

“Wi-Fi Direct works on standards–based Wi-Fi–certified devices… It’s additional functionality beyond what’s in the 802.11 spec. You’ve got to have one device that supports the Wi-Fi Direct spec, and that’s a software upgrade to standard Wi-Fi–certified hardware,” said Kelly Davis–Felner, marketing director at the Wi-Fi Alliance during an interview with her on October 20th.

“We’ll start testing and certifying products next year to that spec. That device can then go make a network with other Wi-Fi devices, several of them at a time, and those devices don’t even need this special kind of software/firmware load. But, you’ve got to have at least one that’s been certified to support the spec in order to make a Wi-Fi Direct connection or group.”

The Wi–Fi Alliance is all about interoperability, Davis–Felner said. “There’s kind of two pieces to it. This is a Wi-Fi Alliance–defined specification that lives on top of the garden variety Wi-Fi MAC PHY. So, if you go and buy an access point or notebook today, we are going to have tested and certified that product to make sure it interoperates. “Rather than IEEE going and writing a specification for how to make these device–to–device connections, the Wi-Fi Alliance went and wrote that specification. And so, we’re finishing that up (that next step), we’ll ship it to our members and they’ll be able to build products to that spec.”

“You’re not undoing anything that exists to the typical Wi-Fi functionality,” she continued, “but then you’re adding on the Wi-Fi Direct protocol that’s defined in the (new) specification. Then what happens is, you bring ’em in, and we test them and certify them. So, a two step thing that we’re doing here. One is, we’re actually defining the specification, which is a little bit different than how we typically operate…(The) IEEE say ‘This is 802.11n,’ and people build products to that, and then we just test the stuff. In this case, we are actually defining the protocol as well.”

If a manufacturer wants to make an existing 802.11 product into a Wi-Fi Direct device, the manufacturer would “…do a software build on (the) device” that will enable it to execute the Wi-Fi Direct protocol, then bring it back in for testing. If it interoperates correctly in the Alliance’s test bed, then it receives the Wi-Fi CERTFIED Wi-Fi Direct seal of approval.

When asked about the existing mesh or peer–to–peer protocols in 802.11, Davis–Felner said that Wi-Fi Direct will work differently from what is typically called “Ad Hoc Mode” in the existing 802.11 spec. “Wi-Fi Direct brings a few things that don’t exist in Ad Hoc today. One of them is rates that can be up to (802 dot)11n in terms of performance. Ad Hoc hasn’t really evolved in the spec over the years, it’s kind of stuck in the 2000s. So, it doesn’t have advanced power saving features, it’s not easy to use, and it doesn’t have good security protection in place. Wi-Fi Direct is addressing those shortcomings…It works differently that Ad Hoc mode, it’s what’s called a ‘soft AP’ model, so the software is essentially turning that Blackberry or whatever device into a software–based access point.”

According to the Wi–Fi Alliance, the first Wi-Fi CERTIFIED Wi-Fi Direct products are scheduled for introduction in mid–2010.

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