As healthcare in many countries faces an aging population and rising costs, mobile sensing technologies promise a new opportunity. Using mobile health (mHealth) sensing, which uses medical sensors to collect data about the patients, and mobile phones to act as a gateway between sensors and electronic health record systems, caregivers can continuously monitor the patients and deliver better care. Although some work on mHealth sensing has addressed security, achieving strong security and privacy for low-power sensors remains a challenge.

We make three contributions. First, we propose Adapt-lite, a set of two techniques that can be applied to existing wireless protocols to make them energy efficient without compromising their security or privacy properties. The techniques are: adaptive security, which dynamically modifies packet overhead; and MAC striping, which makes forgery difficult even for small-sized MACs. Second, we apply these techniques to an existing wireless protocol, and demonstrate a prototype on a Chronos wrist device. Third, we provide security, privacy, and energy analysis of our techniques.