关键词: 等级保护, 多级安全, 数据树, 安全标记, 标记绑定

Abstract: How to bind secure label to information object is always a key problem that restricts MLS from practicality on network. This paper puts forward a method for binding secure label to information object based on unified description of information object. Firstly, this method analyzes types of information objects, and establishes unified description model of multi-types information objects based data tree. Then, an algorithm about binding secure label to information object is given based on traversal of tree. Finally, operations on information object in multilevel security network are discussed. The method can not only unify the method of binding between multi-types information object and secure label, which may improve flexibility of binding, but also accomplish fine-grained mandatory access control, which may solve the problem that access control of heterogeneous data among multilevel secure system is more difficult.

Key words: classified security protection, Multilevel Security（MLS）, data tree, secure label, binding of secure label