摘要： 提出了一种基于实体语义的多级安全数据模型。该模型借鉴了Smith-Winslett 模型基于置信的语义和MLR 模型数据借用的思想。定义了ESM 数据模型，并描述了它的4 个完整性性质和4 个数据操作。ESM 模型消除了语义模糊性，同时又保持了向上的信息流。证明了ESM 模型的正确性、完备性和安全性。

关键词: 多级安全；实体语义；语义模糊性

Abstract: new multilevel secure data model is proposed which is based on the semantics of entities. It borrows the belief-based semantics from Smith-Winslett model and the data-borrow idea from MLR model. This paper defines the ESM data model and describes its four integrity properties and four data operations. ESM eliminates semantic ambiguity and retains upward information flow. This paper proves soundness, completeness and security of ESM.

Key words: Multilevel security; Entity semantics; Semantic ambiguity