A lifetime-optimized end-to-end encryption scheme for sensor networks allowing in-network processing

The use of converge-cast traffic and in-network processing to minimize the amount of transmitted data is a frequently used approach to increase the lifetime of a wireless sensor network (WSN). Consequently when aiming at security for WSNs, one has to focus primarily on protecting this type of traffic. Some recent proposals support the encryption of convergecast traffic with in-network processing. However, they either require the transmission of the sensors’ IDs, creating additional data overhead linear in the number of sensors, or require an elaborate key pre-distribution mechanism. In this paper we propose a solution for end-to-end encryption of converge-cast traffic with a simple key pre-distribution scheme causing additional data only logarithmic in the number of sensors. The scheme is robust with respect to unreliable channels, exhausted nodes and routing flexibility. It supports refreshing the keys at the nodes, which has so far been fully neglected.