支持语义扩展的多关键词密文检索方案

Research on Multi-keyword Encrypted Search with Support for Semantic Extension

现有的多关键词的检索研究集中在支持关键词的精确匹配,文中提出一个支持语义扩展查询的多关键词密文检索方案,基于信息内容计算方法同时考虑到关键词与文档的关系引入TF-IDF技术实现语义扩展;采用平衡二叉树的索引结构,使用安全k近邻算法加密索引向量和语义扩展查询向量,确保计算出准确的相关性得分,实现多关键词排序搜索。通过进行索引和陷门的机密性、查询无关联性等安全性分析表明,本文实现的检索方案是安全的,可以防止内部威胁。

Most of the existing multi-keyword search studies focus on supporting the exact matching of keywords,a multi-keyword encrypted scheme is proposed to supports semantic extension query,and based on the information content calculation method and considering the relationship between keywords and documents,TF-IDF technology is introduced to realize semantic expansion;the index structure of balanced binary tree is adopted,and the index vector and semantic extension query vector are encrypted by the secure k-nearest neighbor algorithm to ensure that the accurate relevance score is calculated and the multi-keyword sorting search is realized.By analyzing the security of the confidentiality of indexes and trapgates,the irrelevance of queries,it is shown that the implemented retrieval scheme is safe and can prevent insider threats.