Two wireless start-ups, Airespace Inc. and Aruba Wireless Networks Inc. have launched in Europe -- and you might be forgiven for confusing the two. As well as both starting with A, they both focus on RF self-calibration, security and real-time applications such as voice. They also both make the bold claim that they can sell their wireless kit even to enterprises that don't want any wireless networking on the premises -- as a means of prevention.