Data Consistency in Sensor Networks: Secure Agreement

Ensuring data consistency in a distributed network in the presence of malicious nodes is a fundamental problem. The resource constraints and security issues make designing mechanisms for information aggregation in large scale networks particularly challenging. We consider distributed sensor network with self-organized nature which requires no cetralized and reliable base station. We propose a general approach to achieve data consistency through secure agreement. In this approach a node collects the information from entire network and corrects its measured value based on the fact that malicious nodes may be present. Several algorithms are presented to solve secure agreement problem. Our model gives a good approximation of the actual value produced by the environment even if a fraction of sensor nodes are corrupted. The best algorithm is communication-ec ient and requires only sublinear communication between sensor nodes.