摘要： 为提高数据库中数值型数据的密文查询效率,提出一种为数据库中数值型数据建立索引的新方法。对敏感数据应用单调递增函数计算得出比较值,应用非单调函数对敏感数据计算求得混淆值,将比较值和混淆值组成索引值并随密文数据一起存入数据库中。密文数据的查询采用两阶段方法,第一阶段查询时先根据查询条件计算得出比较值,将数据库中的索引值去混淆后与其进行比较,筛选出符合条件的密文结果集,第二阶段对一阶段得到的密文结果集解密后查询得到最终所需的结果集。实验结果表明,该方法能够提高数值型数据的密文查询效率。

关键词: 加密处理, 两阶段查询, 数值型数据, 比较值, 混淆值

Abstract: In order to improve the query efficiency of encrypted numeric data,this paper proposes a new method to build index on the numeric data in database.The monotonically increasing function is used to compute the comparison value from sensitive data,and the non-monotonic function is used to compute the confusion value from sensitive data.Then the comparison value and confusion value are connected together to form the index value to store in database.A two-phase method is used to query the encrypted data.In the first phase,the comparison value is computed according to the query condition.Then it is compared with the index value whose confusion part is removed to select out the encrypted result set that matches the query condition.In the second phase,the encrypted result set of the first phase is decrypted and queried to gain the final result set.Experimental results show that the proposed method can greatly improve the query efficiency of encrypted numeric data in database.

Key words: encryption processing, two-phrase query, numeric data, comparison value, confusion value

中图分类号: 

• TP309.2