Higher-Order and Symbolic Computation, 15(4)301-348

Specification Diagrams for Actor Systems

Scott F. Smith, Department of Computer Science, The Johns Hopkins University, Baltimore, MD 21218, USA
Carolyn L. Talcott, SRI International, 333 Ravenswood Ave., Menlo Park, CA 94025-3493, USA

Abstract: Specification diagrams (SD's) are a novel form of graphical notation for specifying open distributed object systems. The design goal is to define notation for specifying message-passing behavior that is expressive, intuitively understandable, and that has formal semantic underpinnings. The notation generalizes informal notations such as UML's Sequence Diagrams and broadens their applicability to later in the design cycle. Specification diagrams differ from existing actor and process algebra presentations in that they are not executable per se; instead, like logics, they are inherently more biased toward specification. In this paper we rigorously define the language syntax and semantics and give examples that show the expressiveness of the language, how properties of specifications may be asserted diagrammatically, and how it is possible to reason rigorously and modularly about specification diagrams.

Keywords: specification, message passing behavior, actor systems, interaction semantics

This article can be downloaded [here]. 		[picture of journal cover]

June 2003 - hosc@brics.dk