Column

Learning From Bluetooth

Network Computing Mobile Observer, March 21, 2007

By Peter Rysavy

Bluetooth has always had tremendous potential, though difficulty in using it has hampered adoption. However, if all goes as planned, personal-area networking will be much easier in the future.

Bluetooth is a wonderful technology, marred only by being extremely frustrating to configure. I have spent more hours setting up Bluetooth connections than any other kind of networking technology. However, once things are working, I've found Bluetooth extremely reliable and useful.
Here are a couple of my recent Bluetooth experiences, the issues involved, and why efforts underway should make life better with next-generation personal-area networks such as ultra wideband (UWB).

Most recently, I tried to configure a Cingular 8525 phone as a modem. And who wouldn't? The phone supports High Speed Downlink Packet Access (HSDPA), a 3G service that Cingular indicates has average throughput rates of 400 Kbps to 700 Kbps, and burst rates of over 1 Mbps. Moreover,
the service allows simultaneous voice and data, meaning you can make or receive calls while on a data connection. I had an older Anycom Bluetooth PC Card in my laptop that I have successfully used for modem connections with the Bluetooth Dialup Networking (DUN) profile and a
variety of other Bluetooth phones in the past. To my dismay, I spent hours trying to get this card to work with my phone. With help from an engineering contact at Cingular (AT&T), we determined that the latest version of Windows Mobile 5 (AKU3) no longer supports the Bluetooth DUN profile. Instead, using the phone as a modem should be done using the Bluetooth PAN profile. After all these years of IT managers finally figuring out Bluetooth DUN, I'm sure Microsoft's phone is ringing off the hook about this decision.

I tried to get an explanation from an unofficial contact at the Windows Mobile group at Microsoft, but received no reply. Okay fine, I thought, I'll use that profile instead, but I had no luck. My Anycom card did not seem to support that profile. So I called Anycom technical support, but
learned my product was no longer supported. Finally, with some intermediate steps that I don't have to space to recount, I purchased a Toshiba Bluetooth USB dongle (meaning the Bluetooth device plugs into a USB port). Based on prior experience, I know Toshiba makes good
Bluetooth products. Sure enough, phone tethering with the mobile phone worked perfectly using the PAN profile. With Microsoft Windows seeing the phone as a network (instead of as a modem), connections were automatic and I must confess, more intuitive than using a dial-up model.
For example, you don't have to enter strange dial numbers or obscure username/passwords. So Microsoft is right. Other than the confusion factor from people trying to use DUN, this looks like a better way to go. At this point, I had over four hours invested. I should mention that
tethering using a USB cable[[isn't the dongle a wireless one? Where's the cable go??]] is much simpler.

The next step was to use Bluetooth for ActiveSync. Sure, I can use the cable, but sometimes it's nice to sync the device without needing a cable. Once again, my initial attempts here would not work. After an e-mail cry for help to Toshiba, I learned that this is challenging to configure, and they weren't sure what my specific problem was. I was only slightly discouraged. Finally I determined that Toshiba installs COM7 as a Bluetooth COM server on the computer, meaning that was the COM number I needed to enter into ActiveSync. I also needed to make COM9 an
outgoing COM port on the phone (obvious, eh?). Then things worked perfectly. That was another four hours. Crazy, I thought. What normal human being would figure all this out. Let me note, however, that getting the Bluetooth headset working (the excellent Motorola H700) took only a few moments.

Anxious at this stage for some good news about personal-area networking, I called MCCI, a leading company that delivers USB drivers under the hood to the industry, and is actively involved with UWB. The next wave of PAN technology, UWB is exciting because it provides extremely high
data throughputs, all the way to 1 Gbps. There is widespread industry support for two types of interfaces. One is Wireless USB, the other is WiNET. I'll discuss these in a future column, as there is lots of good stuff here. Bluetooth itself is evolving to support UWB at the lower layers, allowing easy migration of Bluetooth applications. MCCI informed me that there was more good news. Ease of use is a huge priority for UWB developers, especially in pairing devices together. The Bluetooth
Special Interest Group is leading the charge here with something called Simple Pairing. One planned approach is to use Near Field Communications (NFC), another hot emerging wireless area, where connections occur over extremely short ranges of just inches. With NFC simple pairing, you'll just touch two devices you want to communicate with each other and you'll be done. I can't wait!

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