A secure wake-up scheme for low power wireless sensor nodes

All visions of wireless sensor networks share the idea of small, inexpensive devices, distributed at all scales throughout everyday life. By using their smart phones millions of users were given an ubiquitous controller with a convenient user interface and the capability to set up their own wireless personal area network (WPAN). Smart home, ambient assisted living and health care applications were boosted within the last years by these technologies and are ready to enter the mass market. Critical for these applications are smart battery-driven devices, which enable short response times without scarifying node´s lifetime. In this paper, we describe an approach and the implementation of a software-based secure wake-up scheme for small devices over an unreliable wireless communication link. We will demonstrate that in contrast to common low duty cycle protocols (LDCPs) the message delay can be dramatically reduced without increasing energy consumption. We are convinced that a broad variety of application scenarios in wireless sensor networks will benefit from this technology significantly.