视图发布过程中信息泄漏的测量与消除

Measurement and Elimination of Information Disclosure in Publishing Views

视图发布给数据交换带来了方便,但也带来了安全隐患,在视图发布过程中有可能造成信息的泄漏.因此,保证发布视图的安全成为数据库安全的一个新课题.理论上讲,防止视图发布过程中信息泄漏的方法可分为两种:一种是针对视图接受者,另一种是针对视图发布者.在实际应用中,第1种方法是很难实现的,因此,人们把研究重点都放在第2种方法上.到目前为止,人们提出了有关的评估算法和保护模型,但是它们都不能够从根本上解决问题.为了消除信息泄漏,提出了相对误差的信息泄漏测量方法,并给出了相应的算法,在此基础上,给出了一个基于关键元组的信息泄漏消除算法,并用实验证明该算法能够有效地消除信息泄漏,保证视图的安全.

Although publishing views supply convenience to data exchange, it will potentially threat data owner because some information may be disclosed in the publishing process, so guaranteeing the security of the publishing views becomes a new issue of database security. Theoretically, the methods preventing the information from disclosing in the publishing process can be divided into two kinds, one is for the people who accept views, and the other is for the people who publish views. In practical applications, it is very difficult to realize the first method, so, people focus study on the second method. So far, relevant evaluating algorithms and protecting models have been proposed, for example, query answering, Kanonymity, probabilistic independence event model and so on, but all these methods have the same weakness, namely, limitation and can＇t eliminate information disclosure effectively, so they cannot resolve the problem completely. In order to measure the leakage of the publishing views and eliminate disclosure, an information disclosure measuring method of relative deviation is proposed, which can facilitate the information disclosure calculation, and a disclosure elimination method based on critical tuples is presented, which can eliminate the information disclosure of the publishing views completely. The experiment results show that the information disclosure measuring method of relative deviation can measure information disclosure effectively, and the information disclosure method based on critical tuples can eliminate information disclosure effectively. They can resolve the problem of information disclosure in the publishing process completely, and can guarantee the security of views in the logic level.