Process interface modeling and consistency checking

Abstract The conjunction, disjunction, and exclusive disjunction operators are proposed as extensions to the data flow diagram analysis tool for specifying the input/output interfaces of the processes. These interfaces are expressions which are formed by using the proposed operators. The input/output interfaces of a process P define the semantics of the process P, i.e., if α denotes the input interface and β the output interface of P, then the execution of P requires an instance of α to produce an instance of β. The notion of process interface modeling provides a formal basis for consistency checking in process decomposition. Let α and β be the input/output interfaces of a process P, and N p be a network of subprocesses which refines P. We say that N p is consistent with P if the execution of N p produces an instance of β when given an instance of α. A method for formally testing the consistency of a network of subprocesses with respect to the original process will be described. The method is illustrated by a software design example.