Research on semantic of updatable distributed logic and its application in access control.

The paper presents a distributed logic UD-Datalog whose advantage lies that it extends U-Datalog to distributed environment but still keeps the logic semantic and evaluation method of U-Datalog. The logic presented a new approach to define update in distributed environment based on non-immediate update semantics which distinguishes the language from other distributed datalog. The language is pure declarative and allows us to use top-down and equivalent bottom-up computational evaluation so the already developed techniques for Datalog evaluation can be reused. Firstly, the paper elaborates the syntax and semantic of the logic. Secondly, the evaluation method of the logic is explained. Finally, an application example of the logic in access control of network is discussed which shows the application and expressiveness of the logic. [ABSTRACT FROM AUTHOR]