Specifying Concurrent Program Based on TLA

. The Temporal logic of actions TLA is a logic for specifying and reasoning about concurrent systems, which make systems and their properties are expressed in the same logic. In this paper, we introduce the concurrent programming languages and behavior semantics, mainly describe safety properties and liveness properties in TLA and take NeedhamSchroeder symmetric key protocol as an example to illustrate how to specify these properties in concurrent program by TLA.