It is difficult to knowall the relations between Snort rules. To deal with this problem, the topological relations between Snort rules are classified based on the set theory, and a method for calculating the topological relations between Snort rules is proposed. In the existing methods for analyzing the relations of Snort rules, the relations are usually determined only according to the header information of the Snort rules. Without considering the actions of Snort rules, the proposed method improves upon the existing methods and it can classify and calculate the topological relations between Snort rules according to both headers and options information of Snort rules. In addition, the proposed method is implemented by the functional language Haskell. The experimental results showthat the topological relations between Snort rules can be calculated rapidly and effectively. The proposed method also provides an important basis for conflict detection in the succeeding Snort rules.
数据迁移是大规模存储系统实现负载平衡的重要手段,可有效提高数据访问的性能。然而,现有数据迁移机制大多依赖于集中式算法,存在扩展性方面的不足。提出一种全分布式的数据迁移算法DBDS(Dimension By Dimension Spreading)来解决系统扩展性方面的问题。仿真实验表明,该算法在保证负载全局均衡性的同时,可有效降低迁移过程的消耗,适用于大规模分布式存储系统。
