Cloud-supported Internet of Things (Cloud-IoT) has been broadly deployed in
smart grid systems. The IoT front-ends are responsible for data acquisition and
status supervision, while the substantial amount of data is stored and managed
in the cloud server. Achieving data security and system efficiency in the data
acquisition and transmission process are of great significance and challenging,
because the power grid-related data is sensitive and in huge amount. In this
paper, we present an efficient and secure data acquisition scheme based on
CP-ABE (Ciphertext Policy Attribute Based Encryption). Data acquired from the
terminals will be partitioned into blocks and encrypted with its corresponding
access sub-tree in sequence, thereby the data encryption and data transmission
can be processed in parallel. Furthermore, we protect the information about the
access tree with threshold secret sharing method, which can preserve the data
privacy and integrity from users with the unauthorized sets of attributes. The
formal analysis demonstrates that the proposed scheme can fulfill the security
requirements of the Cloud-supported IoT in smart grid. The numerical analysis
and experimental results indicate that our scheme can effectively reduce the
time cost compared with other popular approaches.

本文提出了一种基于 CP-ABE 的高效安全数据采集方案，通过将数据分块并按顺序使用相应的访问子树进行加密，从而实现了数据加密和数据传输的并行处理，同时采用阈值秘密共享方法保护访问树信息，实现了对敏感且大量的电网数据的安全采集和传输，该方案经过形式化分析证明能够满足智能电网中基于云支持的 IoT 的安全需求，数值分析和实验结果表明与其他流行的方法相比，我们的方案能够有效降低时间成本。