| Similar to the mobile radio that sends and receives wireless voice and data on your Treo, there's a Bluetooth radio that is responsible for wireless communication via Bluetooth. Also like the mobile radio, you can turn the Bluetooth radio on and off whenever you want. The Bluetooth radio has an impact on your device's battery charge, so that's one reason you might consider not leaving the Bluetooth radio on all the time. Another reason has to do with security, which you learn about later in the chapter in the section "Assessing Bluetooth Security Issues." Note The only immediate competitor to Bluetooth is Infrared Data Association (IrDA), which is the infrared technology often found on notebook and handheld computers that enables you to communicate wirelessly with another computer or printer. Although IrDA currently enjoys a much larger install base than Bluetooth, the tide is rapidly turning. The major drawback to IrDA is that it requires a clear line of sight and a distance of no more than about a meter between the two devices that are communicating. Compare this to Bluetooth, which requires no line of sight and a communication distance typically in the 10-meter range.
Regardless of your motives for turning the Bluetooth radio on and off, fortunately it's easy to do. Just follow these steps: 1. | Press the Application button to open the main application screen (if you aren't already there).
| 2. | Press the B key to jump near the Bluetooth application, and then navigate with the five-way navigator to select the Bluetooth application.
| 3. | Press the Center button to launch the Bluetooth application. The Bluetooth screen displays the Bluetooth status along with a couple of options (see Figure 11.1).
Figure 11.1. You use the Bluetooth screen to turn the Bluetooth radio on and off as well as change the Bluetooth device name and make it discoverable. 
| 4. | The On and Off boxes on the Bluetooth screen are used to turn the Bluetooth radio on and off. Just below the boxes you can see the current status of the Bluetooth radio; the appropriate box (On or Off) is also highlighted to show the status. Another option on the Bluetooth screen is the device name, which applies solely to Bluetooth communications. By default, the name you use for device synchronization is used as the Bluetooth device name, but you can change it to any name you want. Just keep in mind that this is the name other Bluetooth devices see when you attempt to connect to them. The final option appears only when the Bluetooth radio is turned on and allows your Treo to be discoverable by other Bluetooth devices, which means that other Bluetooth devices can "see" your device and potentially connect to it.
Note On the near horizon is a competitor to Bluetooth that could ultimately render Bluetooth obsolete: Wireless USB (WUSB). WUSB is a wireless technology based on the popular USB communication standard. Similar to Bluetooth, WUSB is a short-range wireless technology geared toward connecting devices in close proximity. However, WUSB is much faster than Bluetooth, which could be its killer feature. WUSB is slated to have transfer speeds in the neighborhood of 60MB/sec; Bluetooth supports much slower speeds of 1.5MB/sec. Intel is putting a lot of marketing muscle behind WUSB, but it will be tough to shun the wave of new devices that support Bluetooth, including your Treo. It should be interesting to see how WUSB unfolds and whether Bluetooth can survive against it. | 5. | If you plan to connect to a Bluetooth device, go ahead and make sure the Bluetooth radio is turned on. You might also want to leave the Bluetooth application open as you continue reading because you use it again to establish Bluetooth connections.
|
With the Bluetooth radio on, you're ready to connect to a Bluetooth device and communicate over a personal area network. |
