面向隐私保护的两层传感网Top-k查询处理方法

无线传感器网络中的隐私保护技术已经成为研究热点，其中具有隐私保护能力的Top-k查询已经成为富有挑战性的研究问题.提出了一种基于前缀编码验证(PMV)机制的两层传感器网络隐私保护Top-k查询处理方法.通过引入PMV机制，并利用加密和Hash消息身份验证编码技术，使感知节点对采集到的数据进行加密和编码处理，并上传至存储节点；存储节点利用PMV机制实现在无需感知数据明文参与下的数值线性关系比较，进而计算包含查询结果的最小候选密文数据集，并发送给Sink节点；最终由Sink解密密文数据，完成Top-k查询结果计算.为了降低感知节点能耗，给出基于Hash技术的能量优化策略.理论分析和实验结果表明，该方法能够确保数据的隐私安全性，且性能表现优于现有工作.

Privacy-Preserving Top-k Query Processing in Two-Tiered Wireless Sensor Networks

Privacy preservation in wireless sensor networks has attracted more and more attentions recently. Computing top-k query result while preserving data privacy is a challenge in wireless sensor networks. This paper proposes a prefix membership verification (PMV) based privacy-preserving top-k query processing in two-tiered wireless sensor networks, which is denoted as PPTQ. In PPTQ, each sensor node in the query aera firstly converts its collected data into encoded ones by using prefix encoding and hashed message authentication encoding mechanism, and encrypts all the collected data items, then submits the encoded data and the ciphertext to the corresponding storage node. According to the numerical comparison theory of PMV, the minimum candidate ciphertext sets containing the query result will be generated by the covered storage nodes, without knowing the actual values of the collected data items. Then, the storage nodes send the candidate ciphertext to sink, and the final top-k result will be computed by sink after decryption. To reduce the power consumption of sensor nodes, an energy optimization method based on a Hash function is proposed. The theoretical analysis and experimental results show that the PPTQ can ensure the privacy of the collected data and the query result, and it has better performance than the current work in query processing.