Scenario-Based Software Architecture Modeling Using Message Sequence Charts

Modern approaches in software development propose the use of software architectures to help handle the complexity of large software system developments. An important technique to define, analyze, validate, and evaluate a software architecture is through the use of scenarios. A scenario is a brief description of a single interaction of a stakeholder with a system. Scenario modeling is a well-accepted practice among software architects. However, there is no agreement on how to model scenarios. Message Sequence Charts (MSC) is a graphical-textual notation used to specify scenarios. This notation is standardized by the International Communication Union (ITU) and has a well-defined semantics. In this paper we present an approach for describing architectural scenarios using MSC. The paper focuses in the features proposed by the MSC notation to describe complex behaviors and time constraints. In addition, a brief discussion on the advantages of using MSC to validate architectural scenarios is presented. This validation is performed using an executable interpretation of MSC.