Work Remains for Bluetooth

By Jason Brooks  |  Posted 2001-12-12
SAN FRANCISCO—The third annual Bluetooth Developers Conference is less about what the nascent cable replacement technology can do than about what remains to be done.

The sorts of products on display on the expo floor—Bluetooth modules packaged in CompactFlash and PC Cards, USB dongles and headsets—have for the most part made their debuts at previous shows, and the intended usage models for these products have been well defined.

Less well defined, however, are some of the ways in which these products will function reliably and while maintaining interoperability with other Bluetooth products.

One such hurdle involves situations in which multiple Bluetooth piconets, or ad hoc collections of connected devices, interconnect to form scatternets.

The guidelines for managing scatternets are laid out in Bluetooths Personal Area Networking profile. That profile, however, is not yet complete. As a result, certain usage scenarios will yield unpredictable results.

For example, if two laptop computers were each outfitted with a Bluetooth mouse, each system would represent a separate piconet. If a user attempted to transfer a file between the two systems, a scatternet would result and the file transfer, the mouse connections, or both could fail—the outcome would depend on the way that the vendors had interpreted the yet-vaguely defined portions of the Bluetooth specification.

However, several of the key Bluetooth usage models, such as the dial-up networking connection between a mobile phone and a laptop or PDA, are mature enough to deliver reliable performance.

Looking ahead, Microsofts announcement this week to support Bluetooth natively in Windows XP by mid-2002 should make for a stabilizing presence in the Bluetooth world.

While virtually all Bluetooth products currently work with Windows XP, the XP drivers and software from separate vendors often do not work together.

For areas in which gaps in the Bluetooth specification create the possibility of potential incompatibilities, the goal of interoperability with Windows will provide hardware and software developers with a point of reference.

Technical Analyst Jason Brooks can be reached at

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