一种基于安全的网格数据副本策略模型

数据网格中数据副本的存在是为了获得对数据的更好的访问性能，同时也是为解决容错问题而采用的一种冗余技术，但系统复杂程度的增加会带来一系列不可预测的安全隐患。安全与容错是既相互统一，又相互矛盾的关系，应将它们综合起来加以研究。为此将数据副本机制与信息安全结合起来，提出一种决定数据资源副本数量的数学模型。该模型综合考虑服务提供者一方经济利益和声誉度，在合理的假设下对一个两目标的优化问题作了简化处理，通过数值计算和分析确定了数据副本数量的最佳限额。

A Model of Data Replication Strategy Based on Security in Grid

Data replication in data grid is an important technique, by which, better access performance can be got. It is also a fault-tolerant approach, but at the same time brings some hidden trouble for security. Therefore, security and fault- tolerance should be coUigated to research. Combining data replication with security, we proposed a mathematic model which can determine data replication quantity. In this model, taking economic interest and reputation index of service supplier into account, an optimization problem of two targets was simplified under reasonable hypothesis. Numeric calculation and analysis show that there is an optimal quantity for the data replication.