Wi-Fi Direct Just Might Kill Bluetooth--Are You OK With That?

In late 2010, I blogged about Wi-Fi Direct's arrival. Though ad hoc wireless networking has been allowed under 802.11 operations since the standard was a baby, it wasn't exactly easy to execute. Now, Wi-Fi Direct puts a friendly face on device-to-device wireless communications, and some predict that it will seriously horn in on Bluetooth's place in the grand scheme of personal connectivity. Wi-Fi Direct has higher speeds and longer ranges than Bluetooth, so it's easy to see why Wi-Fi Direct may be appealing at first blush. But it isn't the right fit in all cases, and promoting Wi-Fi Direct as the deserving executioner of Bluetooth is a bad move.

The wireless realm is one that thrives on conflicting philosophies. Devices get smaller while networks get faster, and we're willing to cram ever more devices into a shared media technology in the name of mobility and portability.

We sink big dollars into spectrum analysis tools to help identify dozens of interfering devices that we know darn well we probably can't do much about in many cases. We're happy if we see the right number of bars to simply give us a decent connection, whereas on the wire we spit nails if we aren't getting gigabit speeds. It's just a different paradigm.

Within that paradigm, we've learned certain truths. We know that some competing technologies simply can't be tolerated within the radio spectrum used by our WLAN cells, while other ones are OK. Network administrators know that, on the whole, Bluetooth is a fairly good co-inhabitant of the 2.4GHz band used by 802.11n/g/b, especially where the newer frequency-adaptive version 2.x Bluetooth tries to avoid interference with the WLAN. Even where Bluetooth does impact, the effect is usually limited due to the fast and discreet hop pattern employed and its design as a short-range personal area network (PAN) technology.

Which brings us to why Bluetooth should not be allowed to die at the hands of Wi-Fi Direct. Bluetooth knows what it is and needs to be as a PAN technology. With millions of Bluetooth keyboards, mice and headsets in use far and wide in the same spaces where enterprise WLANs operate, the de facto truth is that, despite its potential to interfere at short ranges, we like Bluetooth. We know it well, and if we lose a bit of Wi-Fi speed while we check e-mail during a meeting when the boss uses the Bluetooth keyboard during his PowerPoint presentation, so be it. We also know that no one outside of the room is impacted, and the entire WLAN/Bluetooth equation is easy enough to wrap your head around.Wi-Fi Direct is still very much  Wi-Fi. There is no access point involved, but it is full-powered Wi-Fi, all day long. At home, Wi-Fi Direct may end up being a truly wonderful technology, where the PAN limitations of Bluetooth are often liabilities when we want devices to talk beyond short distances.

But at work, where we need our carefully designed wireless networks to stay carefully designed, Wi-Fi Direct has the potential to become a disruptive, destabilizing element. Few current Bluetooth devices in the business world need the higher speeds and longer ranges of Wi-Fi Direct, and non-infrastructure devices parked right on top of our finite channels and at higher power than the access points in our densely deployed "real" wireless networks is a recipe for disaster. There will forever be places where Bluetooth is just a better fit.

Final word: Wi-Fi Direct is cool and buzz-worthy. But it's also not suited for the enterprise, and getting giddy about it killing off Bluetooth simply because of higher speeds and longer ranges is foolish.