Modeling and analysis of real-time software systems using UML

Real-Time Systems (RTS) should not only function correctly but should also satisfy time constraints. RTS include embedded systems, which are used nowadays in a variety of applications. These are, for instance, house appliances, automotive, aeronautic/aerospace, and health monitoring systems, to mention just a few. The design of such systems is complex and challenging. In order to cope with the complexity of RTS, there is shift in their development to follow a model-driven approach, such as the Model Driven Architecture (MDA), which relies on using models of high level of abstraction. The Unified Modeling Language (UML) is the Object Management Group (OMG) standard modeling language to support MDA. UML is appropriate for software systems because it allows for a multi-view modeling approach through its multitude of diagrams covering the structure, the behavior and the deployment architecture. Moreover, UML is also used in the domain of real-time software systems. This is achieved through its profiles, including, the OMG standard profile for Schedulability, Performance and Time (UML/SPT) or the upcoming standard UML Profile for Modeling and Analysis of Real-Time and Embedded Systems (MARTE). However, UML modeling faces some challenging issues such as model consistency. This issue becomes worse in the context of real-time software systems because additional aspects should be taken into consideration, including time, concurrency and schedulability. In this thesis, we address several issues related to modeling and validation of RTS with UML. We focus in particular on the consistency of UML/SPT models. We adopt an incremental approach to check the consistency of these models by distinguishing the syntactic and semantic levels. The latter is further decomposed into behavioral, concurrency-related and time consistency. Our contributions in this thesis are fourfold. First, we leverage the extensibility mechanisms of UML to propose an extension to UML/SPT. This extension enables the modeling of multicast communications, which is required for the description of the behavior of certain real-time protocols. Second, we propose a formalization of the concurrency modeling capability in UML/SPT using timed automata. This formal semantics allows for applying well-established model checking techniques to check concurrency related consistency in UML/SPT models. Third, we propose an MDA-compliant approach to enable schedulability analysis of UML/SPT models. We present a proof of concept for this approach through a prototype implementation using the Atlas Transformation Language (ATL) and XML-based technologies. Finally, we use the schedulability analysis applied to UML/SPT models in order to check the time consistency of a system design modeled by means of a set of state machines with respect to time constraints modeled using a set of sequence diagrams annotated with UML/SPT time stereotypes. Keywords : Real-time systems, Model-driven Architecture, UML, UML/SPT, Model transformation, ATL, XML, XSLT, Consistency, Concurrency, Model Checking, Schedulability Analysis

Embedding Requirements within the Model Driven Architecture

The Model Driven Architecture (MDA) brings benefits to software development, among them the potential for connecting software models with the business domain. This paper focuses on the upstream or Computation Independent Model (CIM) phase of the MDA. Our contention is that, whilst there are many models and notations available within the CIM Phase, those that are currently popular and supported by the Object Management Group (OMG), may not be the most useful notations for business analysts nor sufficient to fully support software requirements and specification. Therefore, with specific emphasis on the value of the Business Process Modelling Notation (BPMN) for business analysts, this paper provides an example of a typical CIM approach before describing an approach which incorporates specific requirements techniques. A framework extension to the MDA is then introduced; which embeds requirements and specification within the CIM, thus further enhancing the utility of MDA by providing a more complete method for business analysis

A model driven approach for software systems reliability

The reliability assurance of software systems from design to deployment level through transformation techniques and model driven approach, is described. Once the reliability mechanisms provided by current component-based development architectures (CBDA) are designed in a platform-independent way, platform-based design and implementation models must be extended. Current CBDAs, such as Enterprise Java Beans, address a considerable range of features to support system reliability. The evaluation aims to test maturity of the approach, its applicability, and the effectiveness of reliability models. The techniques such as process algebras are generally considered time consuming, in regard to software development

ASPECTS REGARDING THE INTEGRATION OF THE MODERN INFORMATION SYSTEMS

Developing an information system integration strategy, at enterprise level is one of the most difficult issues that the information systems managers must solve, within the present conditions. When settling the integration strategy, two aspects must mainly be taken into account: assuring a complete integration solution of the information systems and building an integration infrastructure of the applications. The present paper aims at presenting few aspects regarding the integration of the information systems at organizational level and describing a specifically developed IBM architecture.information systems integration, software modelling, Model Driven Architecture (MDA), Model Driven Development (MDD)

A Practical Example for Model-Driven Web Requirements

The number of approaches for Web environments has grown very fast in the last years: HDM, OOHDM, and WSDM were among the first, and now a large number can be found in the literature. With the definition of MDA (Model- Driven Architecture) and the acceptance of MDE (Model-Driven Engineering) techniques in this environment, some groups are working in the use of metamodels and transformations to make their approaches more powerful. UWE (UMLBased Web Engineering) or OOWS (Object-Oriented Web Solutions) are only some examples. However, there are few real experiences with Web Engineering in the enterprise environment, and very few real applications of metamodels and MDE techniques. In this chapter the practical experience of a Web Engineering approach, NDT, in a big project developed in Andalusia is presented. Besides, it shows the usability of metamodels in real environments