Architectural patterns are a key point in architectural documentation. Regrettably, there is poor support for modeling architectural patterns, because the pattern elements are not directly matched by elements in modeling languages, and, at the same time, patterns support an inherent variability that is hard to model using a single modeling solution. This paper proposes tackling this problem by finding and representing architectural primitives, as the participants in the solutions that patterns convey. In particular, we examine a number of architectural patterns to discover those primitive abstractions that are common among the patterns, and at the same time demonstrate a degree of variability in each pattern. These abstractions belong in the components and connectors architectural view, though more abstractions can be found in other views. We have selected UML 2 as the language for representing these primitive abstractions as extensions of the standard UML elements. The added value of this approach is twofold: it proposes a generic and extensible approach for modeling architectural patterns by means of architectural primitives; it demonstrates an initial set of primitives that participate in several well-known architectural patterns.

CWI is a founding member of ERCIM, the European Research Consortium for Informatics and Mathematics. CWI's research has a theme-oriented structure and is grouped into four clusters. Listed below are the names of the clusters and in parentheses their acronyms.

Abstract. Architectural styles represent composition patterns and constraints at the software architectural level and are targeted at families of systems with shared characteristics. They enable architectural reuse and hence can bring economy to the design of software architecture. Existing approaches support systematic description of style-based software architectures. Our approach, Alfa, focuses on the construction, instead of description, of style-based software architectures using architectural primitives. This is based on our observation that architectural styles and, indeed, software architectures share many underlying concepts that lead to architectural primitives. Previously, Alfa’s primitives were shown to be sufficient for modeling architectural styles. In this paper, we present the composition of a diverse set of styles for network-based systems using xAlfa, a systematic notation for composing styles from Alfa’s primitives. We then show that two reuse mechanisms in xAlfa, inheritance and composition, enable concise style compositions and unambiguously bring out similarities among architectural styles. 1

Architectural styles represent composition patterns and constraints at the software architectural level and are targeted at families of systems with shared characteristics. While both style-specific and style-neutral modeling environments for software architectures exist, creation of such environments is expensive and frequently involves reinventing the wheel. This paper describes the rapid design of a style-neutral architectural modeling environment, ViSAC. ViSAC is based on Alfa, a framework for constructing style-based software architectures from architectural primitives, and is obtained by configuring Vanderbilt University 's Generic Modeling Environment (GME). Users can define their own styles in ViSAC and, in turn, use them to design software architectures. Moreover, ViSAC supports the hierarchical design of heterogeneous software architectures, i.e., using multiple styles. The rich user interface of GME and support for domain-specific semantics enable interactive design of well-formed styles and architectures.

The codification of software architectural decisions made to address recurring software development challenges results in architectural styles. The primary benefit of architectural styles is that properties demonstrated at the level of a style are carried over into the software system architectures constructed using that style. However, in the absence of comprehensive techniques for checking conformance of a software architecture to its style(s), the expected stylistic properties are not always present in the architecture. This paper argues for a need to look beyond the existing formalizations of styles and architectures to construct style-conformant software architectures.

Abstract Systematic modeling of architectural patterns is a challenging task mostly because of the inherent pattern variability and because pattern elements do not match the architectural abstractions of modeling languages. In this paper, we describe an approach for systematic modeling of architectural patterns using a set of architectural primitives and a vocabulary of pattern-specific architectural elements. These architectural primitives can be used as the basic building blocks for modeling a number of architectural patterns. We introduce profiles for the UML2 meta-model to express the architectural primitives. The use of the primitives along with the stereotyping scheme is capable of handling some of the challenges for the systematic modeling of architectural patterns, such as expressing pattern participants in software design.