Abstract not found

An important goal in software engineering is to describe complex software systems at an architectural level of abstraction. While there are many useful architectural paradigms (pipes, blackboards, etc.) they are typically understood only idiomatically and applied in an ad hoc fashion. We show how a formal model allows us to say precisely what we mean by a software architecture, explore its properties, and systematically describe instances of the architecture. We illustrate the approach using the well-known example of pipe-filter architectures. This research was sponsored by the National Science Foundation under Grants CCR-9109469 and CCR-9112880, and by Siemens Corporate Research, Inc. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the official policies, either expressed or implied, of Siemens or the U.S. Government. Keywords: Dataflow Systems, Pipes and Filters, Software Architecture, Software Engineering, S...

This paper argues that with the advent of explicitly speci ed software architectures, testing can be done e ectively at the architectural level. A software architecture speci-cation provides a solid foundation for developing a plan for testing at this level. We propose several architecture-based test criteria based on the Chemical Abstract Machine model of software architecture. An architectural (integration) test plan, developed by applying selected of these criteria, can be used to assess the architecture itself or to test the implementation's conformance with the architecture. This facilitates detecting defects earlier in the software lifecycle, enables leveraging software testing costs across multiple systems developed from the same architecture, and also leverages the e ort put into developing a software architecture. 1

This article reviews the growing body of scientific work in Artificial Chemistry. First, common motivations and fundamental concepts are introduced. Second, current research activities are discussed along three application dimensions: modelling, information processing and optimization. Finally, common phenomena among the different systems are summarized. It is argued here that Artificial Chemistries are "the right stuff" for the study of pre-biotic and bio-chemical evolution, and they provide a productive framework for questions regarding the origin and evolution of organizations in general. Furthermore, Artificial Chemistries have a broad application range to practical problems as shown in this review.

The description of a software architecture style must include the structural model of the components and their interactions, the laws governing the dynamic changes in the architecture, and the communication pattern. In our work we represent a system as a graph where hyperedges are components and nodes are ports of communication. The construction and dynamic evolution of the style will be represented as context-free productions and graph rewriting. To model the evolution of the system we propose to use techniques of constraint solving. From this approach we obtain an intuitive way to model systems with nice characteristics for the description of dynamic architectures and recon guration and, a unique language to describe the style, model the evolution of the system and prove properties. 1

When constructing software systems from existing components, the engineer is faced with the problem of potential conflicts in the interactions among the components. Of particular difficulty is guaranteeing compatibility in the dynamic interaction behavior. Using an architectural description of the system and its intended components, the engineer can reason about the interactions early and at a high level of abstraction. In this paper we give a case study of the Compressing Proxy system, which was first investigated by Garlan, Kindred, and Wing. We present architectural specifications and analyses of two versions of the system. One version is a seemingly obvious melding of the components. The other is a solution to deadlock problems uncovered by formal analyses of the #rst version. We use the Chemical Abstract Machine as an example of an architectural description formalism that can help uncover architectural mismatches in the behavior of components.

. We enhance Gamma, a multiset rewriting language, with a notion of structured multiset. A structured multiset is a set of addresses satisfying speci#c relations which can be used in the rewriting rules of the program. A type is de#ned by a context-free graph grammar and a structured multiset belongs to a type T if its underlying set of addresses satis#es the invariant expressed by the grammar de#ning T.We de#ne atype checking algorithm which allows us to provemechanically that a program maintains its data structure invariant. Keywords: multiset rewriting, graph grammars, type checking, invariant, veri- #cation. 1 Gamma: motivations and limitations Gamma is a kernel language which can be introduced intuitively through the chemical reaction metaphor #2, 3#. The unique data structure is the multiset whichcanbe seen asachemical solution. A simple program is a pair #Condi- tion, Action# called a reaction. Execution proceeds by replacing in the multiset elements satisfying the condition b...

Developing notations and tools for describing and analyzing software architectures is currently a main research issue in software engineering. Although there is no universally accepted definition, most researchers agree that an Architectural Description Language should allow to describe and analyze the structure of large software systems. This paper shows that PoliS, a coordination language, can be effectively used to design and analyze software architectures. We demonstrate that PoliS satisfies the requirements of ADLs and develop a model checking framework to reason on PoliS specifications.

In previous papers we have addressed the problem of deriving from an architectural description pieces of information useful to drive testing [2, 3]. Our approach is based on the use of the CHAM formalism for architectural

Component-based software development is generally accepted as a promising paradigm to develop large scale and complex software effectively. Software architecture is a core technology to realize the vision of software plug-and-play. In WRIGHT, an architectural description language, potential deadlocks caused by erroneous interaction of connectors can be automatically detected by a model checker called the FDR (failure divergence refinement). However, analysis that connector level WRIGHT description is free from deadlock is inadequate. That is, deadlocks can still be caused by an erroneous interaction of component's internal events. In this paper, we extend...