数据库的密文索引机制

根据加密数据库的特点，分析了建立密文索引需要考虑的主要因素，提出了采用B＋树实现密文索引的方法以支持动态结构调整和顺序查找。同时还提出了一种压缩技术来提高系统效率，减少I／O次数，分析了在这种环境下选取参数m的方法。此法比采用二叉树的方案更加快捷，效率更高，并且不需要额外开销。最后，分析了系统的安全性并指出了有待进一步研究解决的一些问题。

Ciphertext index mechanism for database system

According to the characters of the ciphertext database, the major factors to create a ciphertext index are analyzed. This article puts forward a method to implement the ciphertext index to support dynamic structure modification and sequential query by using B+ tree. In order to enhance the efficiency of the system and reduce the I/O burden, a compress technique is suggested simultaneously. Method concerned with the decision of the parameter m is discussed in this given environment. This method is faster, more convenient and more efficient than the one by using binary tree, and no additional cost is required. Finally, this article analyses the secure characters of anti attack strategies and points out several problems to be resolved in the further work.