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A Secure Data Aggregation Approach in Hierarchical Wireless Sensor Networks

As wireless sensor networks (WSNs) are employed in many applications, security of these networks must be ensured. Considering the limited resources of nodes in WSNs, it is a critical challenge. Meanwhile, the deployed nodes are separated and they need to cooperatively transmit the sensed data to the base station. To reduce the amount of sending data, an aggregation approach can be applied along the path from sensors node to the sink. However, usually the carried information contains confidential data. Therefore, a security aggregation approach is required. An efficient security data aggregation scheme using the renewable hash chain is proposed in this paper. The scheme provides data authentication, confidentiality and integrity for the WSNs. The system is implemented with the real nodes. The result shows that the proposed scheme is secure and efficient.