Eckhardt Holz

Application of UML Within the Scope of New Telecommunication Architectures

The telecommunication market is one of the fastest growing markets in the last years. Deregulation in the provider market, new techniques and user demands lead to more flexibility but require also the coexistence of legacy telecommunication systems with new and more advanced technologies. Although being known conservative in the introduction of new technologies, the new requirements have forced the industry to increase the time-to-market for new services and to apply new reference architectures. This paper investigates, how the new object oriented modeling language UML (Unified Modeling Language) can be applied in this domain.

A method for the design and development of distributed applications using UML

Presents a design and development method for distributed applications running on top of advanced object-oriented middleware platforms. We introduce the basic concept of the distinction between a set of concepts and their relations, the definition of a notation supporting such concepts and rules for automatic code generation that help to provide a smooth transition from the design step to the implementation stage. Although the set of concepts is based on RM-ODP (Reference Model for Open Distributed Processing), we refine a number of ODP definitions in order to reflect practical design tasks. The supporting notation we present rests upon the customization of the Unified Modeling Language (UML). Automatic code generation issues are presented briefly, taking a extended CORBA 2.3 object middleware as the target distributed infrastructure.

An attempt to embed a restricted version of SDL as a target language in Focus

This paper presents a first attempt to embed a restricted version of SDL as a target language in Focus. Brief introductions to both Focus and SDL are given, and it is shown how both methods can be assigned a denotational semantics based on streams and stream processing functions. A set of Focus specifications, referred to as F-SDL, is characterized whose elements structurally and semantically match SDL specifications to such a degree that an automatic translation is almost straightforward. Finally it is outlined how Focus can be used to develop an SDL specification of a protocol.

Tool-based language development

This paper shows how to tackle the problem of ever larger languages and the problem of combining multiple languages. The central idea is to build a foundation for language definitions that uses a metamodel-driven approach with support of language engineering tools. Thus development and further evolution of languages will be transformed from the traditional paper- and -pen style into an engineering activity. This allows an early detection of problems within the language definition and increases the reliability of the language and the supporting tools.

Manufacturing software components from object-oriented design models

The paper presents a model-based approach to support the design of component based distributed applications through the provision of a suitable MOF based meta model in combination with a UML profile as supporting notation and code generation rules for CORBA-middleware platforms. The meta-model enables structural definitions of object types whose implementations are contained in components. It supports the specification of their configuration properties as well as interaction policies for communication between these objects. The modeling concepts also allow for the combination of different interaction types, which are operational, signal and continuous media interaction.

Structural and behavioral decomposition in object oriented models

The decomposition of large systems into parts is a general principle of software design. Even more, in the scope of distributed systems, a partition of the whole system into distributable components is necessary. Decisions about what constitutes a component of a system are usually either based on the behavior or on the structure of the system. Nevertheless, there is a strong mutual influence between both kinds of decomposition. Despite the importance of structural and behavioral decomposition, many modeling notations and languages define the semantics of these concepts rather vaguely, and this may lead to incorrect implementation. This paper presents the new structuring mechanisms in the object-oriented specification and description language SDL-2000. The paper also gives a critical evaluation of these concepts and a comparison with similar approaches in UML (Unified Modeling Language) and ROOM (Real-time Object-Oriented Modeling).

Improving the development and validation of viewpoint specifications

This paper presents an overview of the application of ITU-SDL for the development of distributed systems according to the RM-ODP. The use of the advanced Site tools for the simulation and prototype code generation of/from SDL specifications of computational as well as engineering objects is illustrated. The advantages of this approach are shown by applying it on the ODP trading function as an example. Furthermore, concepts and principles for a smooth, semi-automatic SDL based transition between viewpoints, which are currently under development, are sketched out.

A Development Method for SDL-92 Specifications Based on OMT

This paper sketches a combination between OMT used for analysis and SDL-92 used for design and simulation purpose. It is a part of a methodology for the design of hybrid hardware/software systems which is being developed within the ESPRIT Project INSYDE [2].

A formal approach to HW/SW co-design: the INSYDE project

The paper presents a formal approach to the co-design of hybrid systems based on object-oriented analysis and design, and the formal description languages VHDL and SDL. This methodology covers the whole development process from requirements capture, through design and implementation, to validation. The paper also presents some of our experiences to date with the methodology.

Validation of hybrid systems by co-simulation

This article describes the INSYDE3 methodology for the design of hybrid systems. This methodology covers the development life-cycle from initial requirements capture, through design and implementation, to validation. The validation of a hybrid system is achieved by co-simulating a formal description of the hybrid system. This formal description is derived from the initial requirements capture by integrating an object-oriented analysis and modelling tool, OMT, with two domain-specific formal description languages, SDL and VHDL, for the description of the software and hardware subsystems respectively. The automatic translation of the system, described in a formal variant of OMT, to SDL and VHDL ensures that descriptions of the software and hardware subsystems together form a coherent description of the hybrid system. The article describes how this formal description forms the basis for co-simulation. The advantages of using heterogeneous co-simulation for validating hybrid systems are described, and the article shows how the methodology, and supporting tools, support the co-simulation by automatically generating the necessary code to connect and synchronise the individual SDL and VHDL simulators.