e-based system that promises to replace a mobile phone tower's room full of communications hardware with a single computer. The system is designed to making personal communications more affordable, particularly for small, rural communities. The software is also capable of running emergency communications-such as MORE EFFICIENT BASE STATIONS police, fire, and ambulance channels-on the same device as the civilian system, eliminating the need for a separate network of emergency communi- cations towers. "Rural customers are the first application of the technology, but large carriers are watching to see what happens," says John Chapin, chief technology officer at Vanu. Vanu scientists developed and tested the software with funds from the National Science Foundation, the federal agency that supports science and engineering research and education. Although not yet commercially available, the technology is beginning to attract the attention of service providers nation- wide. "When the telecom industry crashed, Vanu technology caused wireless operators to look at deployments differently," says Sarah Nerlove, the NSF Small Business Innovation Research program officer who oversees Vanu's awards. "Vanu was an ideal fit for their changing needs." Mobile phone towers dot the landscapes of cities and suburbs, providing millions of Americans with access to wireless communications. At the base of each tower is an air-conditioned shelter filled with expensive equipment called a base station. "As technology advances, all of that equipment continually needs to be overhauled or replaced," says Chapin. Besides replacing much of a base station's hardware with a single server, radio software can aggregate equipment from many stations into a single location that communications engineers call a "base station hotel." Vanu Software Radio performs all of the functions of a global system for mobile communications (GSM) base station using only software and a non- specialized computer server. The servers run the Linux operating system on Pentiu