Yvon Kermarrec

GARLIC: generic Ada reusable library for interpartition communication

This paper presents an implementation of the distributed programming features of Ada 95 within the GNAT system. The work we describe is the result of an international collaboration whose goal is to produce a high level environment for distributed system programming. This paper focuses on issues of interprocessor communication, since this is the core element of our software architecture. We describe the design and implementation of GARLIC, an interface between the network and the application. GARLIC is an extension of the predefined interface specified by System.RPC.

Reliable Software Technologies – Ada-Europe 2009

This book constitutes the proceedings of the 14th Ada-Europe International Conference on Reliable Software Technologies, Ada-Europe 2009, held in Brest, France, on June 8-12, 2009. The 19 papers presented were carefully reviewed and selected from numerous submissions. Topics of interest to the conference are methods and techniques for software development and maintenance; software architecture; enabling technology; software quality; theory and practice of high-integrity systems; embedded systems; mainstream and emerging applications; ada language and technology; ada and education.

Providing fault-tolerant services to distributed Ada 95 applications

Yvon Kermarrec and Laurent Nana Telecom Bretagne Departement Informatique F 29 285 Brest Cedex France yvon. kerm arrec@ens t-bretagne. fr laurent.nanatchamnda@enst-bretagne.fr In this paper, we present various techniques and approaches for fault tolerance. We have selected recovery blocks and have already implemented this mechanism into an Ada95 environment. We extend this notion of recovery blocks to deal with distributed applications.

A distributed shared virtual memory for Ada 83 and Ada 9X applications

This paper presents our experience in developing a toolaet for distributed applications in Ada. Ada has been chosen as our programming language because it offers software engineering concepts and an interesting tasking model. In this paper wc shall present, among other things, a software component which implements a distributed shared virtual memory and which thus allows distributed Ada applications to communicate using a single address space. Our approach is based on an existing algorithm but we have extended it in order to tackle Ada peculiarities. This software component is a key component in our toolaet as it can be used either at the programmer level or at the level of the kernel implementor.

PARIS - Partitioned Ada for Remotely Invoked Services

This paper presents our experience implementing the Ada 95 Annex E to support distributed systems using the GNAT compiler[6]. The work has been performed by a multinational team from France and the USA. The paper describes the implementation of the Partition Communication System and the required support from the GNAT compiler. In addition, extensions beyond Annex E are described that facilitate programming the next generation of distributed applications in Ada 95.

Extending Enterprise Architecture Modeling Languages: application to telecommunications service creation

Enterprise Engineering offers a global view on multiple concerns such as processes, stakeholders, supporting technology. This global view is sustained by Enterprise Architecture frameworks, languages, tools and standards. The current effort has been focused on general purpose Enterprise Architecture frameworks, modeling languages and tools, which allow describing a wide range of domains. While they are expressive enough at the business layer, at the technical layer, where more detail is needed to describe a domain specific system, such general purpose Enterprise Architecture Modeling Languages sometime lack the semantic strength required. The concepts present in the language are too abstract, they need refinement and specification. To provide the necessary specific semantic strength, this paper proposes an approach to extend Enterprise Architecture Modeling Languages with domain specificity. The proposed approach is a model-driven one, allowing a high degree of automation in the building of tools for the language extension. To better show its benefits, the approach is applied on the domain of Telecommunications, for defining an Enterprise Architecture Modeling Language extension for service creation. The so defined language and its associated tools are illustrated on an IP Multimedia Subsystem conferencing service example.

Static/Semi-Dynamic and Dynamic Composition of Services in Distributed Systems

In an earlier context, we have proposed a metadata model for service description. It describes service by three levels of properties: static properties (like its provider, its location and so on), behavior and interface. We have used ontologies in order to index and store the properties provided by this model. We have developed and implement tools which constitute a trader based on ontologies to discover a service by querying its three levels of description from ontologies. Based on the metadata model that we have proposed, we propose in this paper, an approach which allows the client to compose and to combine services by using our trader. This approach defines three models of composition : static, semi_dynamique and dynamique. These models allow the client to benefit from the functionalities of more than one service and to combine them at run-time and at compile-time to get novel services which provide novel functionalities.

CORBA vs. Ada 95 DSA: a programmer's view

Recent evolutions in computer networks have made it possible to consider distributed platforms as possible architectures for numerous applications. The classes of distributed applications are numerous and go from time consuming application (performance quest) to geographically distributed applications through safety and critical softwares. As beforehand, hardware evolutions have been fast paced and much earlier than software techniques to build applications on these distributed targets. In this paper, we shall investigate and compare three different approaches: the language approach of Ada 95 for distributed systems vs. two distributed platforms. And for this evaluation, we shall take the developers view, that is to go beyond the technical response but to take into account the developer of the distributed application.

Ada-Linda: a powerful paradigm for programming distributed Ada applications

In spite of recent advances in hardware and computer technology, we still face a daunting task when programming parallel or distributed systems. The difficulties are linked to the expression and control of concurrent activities and to their communication and synchronization. In this context, our approach is to introduce software engineering features in a domain where these notions are not widely used. We have in mind a set of reusable software components which address various issues related to distributed system programming: control, communication and paradigms. In this paper, we present the Linda model which offers an interesting paradigm for the distribution of Ada applications.

Ada communication components for distributed and real time applications

ThM paper presents our experience in developing d= tributed applications in Ada. Ada has been chosen as our programming language because it offers software engineering concepts and an interesting tasking model. In this paper we shall present software components which allow communication between applications. These components have been designed through a systematic approach and implement the latest recommendations of standardization committees. These components can also be considered as the basic elements for the design of d~tributed kernels.