基于Huffman树的密文索引构建方案

Scheme of ciphertext index construction based on Huffman tree

为实现安全高效的云端数据密文检索,提出基于Huffman树的密文索引构建及检索方案。将Huffman树型结构及其编码的思想引入密文索引结构的构建方案中,改进基于知识理解的中文分词算法提取明文关键词,通过改进的TF-IDF规则对检索结果集进行排序以返回最符合用户需求的Top-k个结果,并增加伪造的索引节点以增强索引结构的抗统计分析攻击能力。通过实验测试和性能对比分析可得出结论:方案在保证密文和索引信息安全性的同时,可以提高密文检索的效率。

To achieve safe and efficient ciphertext retrieval of data in cloud,this paper proposed a scheme of ciphertext index construction and retrieval based on Huffman tree.The scheme introduced the idea of the Huffman tree structure and its coding into the construction of ciphertext index structure,improved Chinese word segmentation algorithm based on knowledge understanding to extract keywords of plaintext,sorted the search result set through the improved rule of TF-IDF to return the Top- k results that meet the users’ needs mostly,and added forged nodes of ciphertext index to enhance capabilities of resistance to statistical analysis of the index structure.Through the experimental test and comparison analysis of performance,it can be concluded that the scheme can improve the efficiency of ciphertext retrieval,which can ensure the security of ciphertext and index simultaneously.