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Bluetooth Overview

Bluetooth is a cable-replacement technology designed to wirelessly connect peripherals, such as mice and mobile phones, to your desktop or laptop computer and to each other. An inexpensive, low-power, short-range radio-based technology, Bluetooth is not a wireless networking solution, such as AirPort. Rather, it is an alternative to the IrDA (Infrared Data Association) standard. Although the IrDA standard, too, supports wireless communication between peripherals and computers, it has two limiting requirements. First, IrDA devices must be very close, no more than about 1 meter apart. Second, the communicating devices must have a direct line of sight to each other.

Because it relies on radio waves, however, Bluetooth communication overcomes these strict requirements:

• Bluetooth devices can communicate at ranges of up to 10 meters.

• Bluetooth devices do not need to be in direct sight of each other.

This makes Bluetooth communication much more flexible and robust. It’s also important to note that because Bluetooth excels at low-bandwidth data transfer, it is not intended as a replacement for high-bandwidth cabled peripherals. For high-bandwidth devices, such as external hard drives or video cameras, cables are still the best option.

Apple's Bluetooth support is integrated into Mac OS X, version 10.2 and later, and is based on the Bluetooth Special Interest Group (SIG) specification (discussed in “Bluetooth Architecture”). Apple also provides some high-level bridges between Mac OS X functionality and the Bluetooth protocol stack. This means that many Bluetooth devices work transparently with computers running Mac OS X version 10.2 and later. The Mac OS X HID Manager, for example, handles a Bluetooth mouse just as it does a cabled mouse. In many cases, such high-level bridges allow your application to handle Bluetooth devices without including any Bluetooth-specific code.

Other applications may need to access Bluetooth-specific attributes and messages. For them, Apple provides a comprehensive API that allow you to take advantage of Bluetooth’s unique features. Be sure to read “Bluetooth on Mac OS X” for a description of the Bluetooth API available in Mac OS X version 10.2 and later. For concrete examples showing how to use Apple’s Bluetooth API, see “Developing Bluetooth Applications.” Note that Apple does not provide a separate API for socket-based access to Bluetooth devices; instead, use the APIs described in “Bluetooth on Mac OS X.”

In this section:

What Bluetooth Does Best
Future Directions for Bluetooth

What Bluetooth Does Best

The characteristics of Bluetooth technology—low cost, low power, and radio based— encouraged the concept of a personal area network (PAN). A PAN envelops the user in a small, mobile bubble of connectivity that is effortlessly available at any time. Bluetooth’s freedom from cables and potential ubiquity make it ideal for carrying your personal network around with you.

With a PAN, the possibilities are limitless:

• Imagine being able to connect to the Internet on a dial-up connection you access through your mobile phone. Surfing the Internet then becomes possible anywhere your mobile phone can connect to your internet service provider.

• Perhaps you prefer to use a traditional mouse with your laptop. Choose a Bluetooth-enabled mouse and you won’t have to keep track of a mouse cable.

• If you have a Bluetooth-enabled mobile phone that stores your business information in the Vcard format, you can easily share this information with your colleagues. Swap your Vcard with theirs, by wirelessly connecting to their Bluetooth-enabled mobile phones.

Future Directions for Bluetooth

Industry analysts predict the growing popularity and availability of Bluetooth-enabled devices. This in turn raises consumer expectations for mobile PANs and provides many opportunities for vendors to create new products. At the end of 2003, the Bluetooth SIG released the second version (version 1.2) of the Bluetooth specification. This successor to version 1.1 provides a number of improvements, including:

• Enhanced quality of service (QOS). This guarantees that your human-interface (and other QOS) devices will get the time to transfer data when they need it.

• A more adaptive frequency-hopping algorithm. The new algorithm increases communication reliability and decreases interference from other wireless emitters operating the same frequency range.

Apple’s ongoing support for Bluetooth communication is evidenced by frequent Bluetooth software updates and up-to-date SDKs. Using the software frameworks and built-in support Apple provides, you can bring your Bluetooth applications to Mac OS X with ease. Apple is committed to helping you find ways to provide your customers with the wireless connectivity they need.

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