Secure and resilient scheme for data protection in unattended wireless sensor networks

Unattended Wireless Sensor Networks (UWSN) are usually deployed in human-hostile environments. Such architectures raise a challenge to data protection for two main reasons. First, sensors have limited capacities in terms of performance and memory, so not all cryptographic mechanisms can be applied. Moreover, the measurements cannot be immediately gathered, so they have to be kept inside the devices until a mobile sink comes to collect them. This paper introduces a new method for secure and resilient data protection inside UWSN. It is based on a lightweight fragmentation scheme that transforms data collected by a sensor into multiple secure fragments that are distributed over sensor's neighboring nodes in a way that only a certain amount of these fragments is required for data recovery. Moreover, data security is reinforced by the use of a dynamic key refreshed after each visit of the mobile sink. Authentication and integrity information are dispersed within the fragments to protected data from active attacks. Homomorphic properties of the algorithm allow to significantly reduce storage space inside the nodes. Performance and empirical security evaluation results show that the proposed scheme achieves a good trade-off between performance, data protection and memory occupation.