ring manufacture. This would allow the manufacturer to track inventory in every store and soda machine au- tomatically and dispense new inventory promptly. Some market studies show that the cost reduction and reduced cycle time offered by such a system actually would pay for its deployment and maintenance. Allowing ourselves to be truly speculative for a mo- ment, we would point out that telemetry provides more than just location. Why not in- clude a thermometer so that the soda bottle (or, more important, the ice cream bar) can call for help when the refrigeration shuts down? More realistically, such systems will be useful in more expensive pieces of equipment. They also will be valuable to society as we focus more and more on security. A new sys- tem for vehicular security at airports has passed its proof-of-concept stage and is being prototyped at a major airport. Fuel trucks and smaller vehicles are potential weapons for terrorists who might use them to attack commercial aircraft. In the prototype sys- tem, ignition keys are replaced with an electronic key. If a key is reported lost, then it is locked out of the system. A wireless airport network is notified any time anyone tries to start a vehicle. The vehicle transmits information on the key to the network by a wireless system. The network confirms the key owner's identity, work status (whether or not the employee should be working at this time), and right to use that particular vehicle. If that worker should not be driving that vehicle at that time, the vehicle shut down, and security is notified. If all is okay, then the vehicle starts. Going one step further, the system tracks each vehicle's location with a fair degree of precision and can Downloaded from Digital Engineering Library @ McGraw-Hill (www.digitalengineeringlibrary.com) Copyright © 2004 The McGraw-Hill Companies. All rights reserved. Any use is subject to the Terms of Use as given at the website. CDMA Now and in the Future Conclusion shut a vehicle down automatically if it enters an unauthori