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Hierarchical Key Management Scheme with Multilevel Secure Access

With the rapid expansion of IoT, data collected by sensors and intelligent devices has a great value to Big Data analysis. However, privacy leakage is becoming one of most challenging concerns in information collection, sharing or analysis, and threatening the security of information economy such as data as a service. In this paper, we focused on the dynamic changes of the relationship of resource-constrained data suppliers and demanders, and proposed a hierarchical key management scheme with multilevel secure access (ML-HKM) based on Elliptic Curve Discrete Logarithm Problem. We present the system operations including setup, update, join and revoke to securely obtain the data encryption key and the multilevel mapping method to enhance the network extensible. At last, the scheme is analysed in correctness and security which indicates it is both forward secrecy and backward secrecy.