The World of Bluetooth

Bluetooth is a wireless specification intended to replace the need to use physical cables between devices. Bluetooth, for example, enables you to wirelessly connect keyboards, mice, and printers to your laptop or computer. You also can use Bluetooth to wirelessly connect a mobile phone to your computer or laptop to sync settings, transfer photos or videos, or share contacts. Many other types of Bluetooth devices are available as well, including ones that don’t even connect to computers or laptops such as devices used inside automobiles, exercise equipment, and games.

Bluetooth uses radio waves to transmit signals, much like many other types of technologies such as FM radio, television, and Wi-Fi. One primary difference between Bluetooth and other radio wave technologies is the distance between devices. Bluetooth is designed for very small distances; the idea is that Bluetooth is personal. You set up connections between your devices in a personal area network (called a PAN). Bluetooth is good within about 164 feet (50 meters), whereas other radio wave technologies can reach miles or hundreds of miles.

At the time of this writing, the current Bluetooth version is 4.0. Bluetooth 4.0 introduced low-energy wireless transfers to allow small, low-powered devices to use Bluetooth. Transfer rates allow data to be sent at up to 25 Mbps (megabytes per second, which is quite fast. If you’re thinking of setting up a permanent wireless network between computers, however, you may want to stick with the 802.11 standards described in Chapter 49, “Creating a Home Network.” But when it comes to connecting non-computer Bluetooth devices, wirelessly connecting a printer, or occasionally transferring files between computers, Bluetooth can’t be beat.

The following are some Bluetooth buzzwords and concepts that you’ll encounter in this section as well as in the instructions that come with Bluetooth devices:

• Discovery: A Bluetooth device finds other Bluetooth devices to which it can connect through a process called discovery. To prevent Bluetooth devices from connecting at random, discovery is usually turned off by default on a Bluetooth device. You manually turn on discovery when you are ready for that device to be discovered. After a device has been discovered, you can turn discovery off.
• Discoverable: A discoverable (or visible) Bluetooth device is one that has discovery turned on, so other Bluetooth devices within range can see and connect to the device.
• Pairing: Once two or more Bluetooth devices have discovered one another and have been paired (connected), you can turn off their discovery features. The devices will forever be able to connect to one another, and unauthorized foreign devices will not be able to discover and hack into the paired devices.
• Encryption: A process by which transferred data is encoded to make it unreadable to any unauthorized device that picks up a signal from the device. Bluetooth offers powerful 128-bit data encryption to secure the content of all transferred data.
• Passkey: Similar to a password, only devices that share a passkey can communicate with one another. This is yet another means of preventing unauthorized access to data transmitted across Bluetooth radio waves.
• Bluejacking: A process by which one user sends a picture or message to an unsuspecting person’s Bluetooth device.

A non-computer gadget such as a smart phone, MP3 player, or electronic pedometer that supports Bluetooth is called a Bluetooth device. A standard desktop PC or laptop computer usually isn’t a Bluetooth device, although many laptops do include built-in Bluetooth capabilities. As a rule, it’s easy to turn your PC or laptop into a Bluetooth device. You just plug a Bluetooth USB adapter — a tiny device about the size of your thumb — into any available USB port, and presto, your computer is a Bluetooth device. Making your computer into a Bluetooth device doesn’t limit it in any way. It just extends the capabilities of your computer so that you can do things such as:

• Connect a Bluetooth mouse, keyboard, or other pointing device
• Use the Devices tool in the PC Settings area to add a Bluetooth device
• Use the Add Printer Wizard to use a Bluetooth printer wirelessly
• Use a Bluetooth-enabled phone or dial-up device as a modem
• Transfer files between Bluetooth-ready computers or devices by using Bluetooth
• Join an ad hoc personal area network (PAN) of Bluetooth-connected devices (an ad hoc network is an informal network, where devices connect and disconnect on an as-needed basis, without the need for a central hub or base station)

When you install a Bluetooth adapter on your PC or laptop, you also install radio drivers. Windows 8 comes with many radio drivers preinstalled.