Implementing fault tolerant applications using reflective object-oriented programming

Abstract: Shows how reflection and object-oriented programming can be used to ease the implementation of classical fault tolerance mechanisms in distributed applications. When the underlying runtime system does not provide fault tolerance transparently, classical approaches to implementing fault tolerance mechanisms often imply mixing functional programming with non-functional programming (e.g. error processing mechanisms). The use of reflection improves the transparency of fault tolerance mechanisms to the programmer and more generally provides a clearer separation between functional and non-functional programming. The implementations of some classical replication techniques using a reflective approach are presented in detail and illustrated by several examples, which have been prototyped on a network of Unix workstations. Lessons learnt from our experiments are drawn and future work is discussed

Secure Method Invocation in JASON

We describe the Secure Method Invocation (SMI) framework implemented for Jason, our Javacard As Secure Objects Networks platform. Jason realises the secure object store paradigm, that reconciles the card-as-storage-element and card-as-processing-element views. In this paradigm, smart cards are viewed as secure containers for objects, whose methods can be called straightforwardly and securely using SMI. Jason is currently being developed as a middleware layer that securely interconnects an arbitrary number of smart cards, terminals and back-office systems over the Internet

Tracking decision-making during architectural design

There is a powerful cocktail of circumstances governing the way decisions are made during the architectural design process of a building project. There is considerable potential for misunderstandings, inappropriate changes, change which give rise to unforeseen difficulties, decisions which are not notified to all interested parties, and many other similar problems. The paper presents research conducted within the frame of the EPSRC funded ADS project aiming at addressing the problems linked with the evolution and changing environment of project information to support better decision-making. The paper presents the conceptual framework as well as the software environment that has been developed to support decision-making during building projects, and reports on work carried out on the application of the approach to the architectural design stage. This decision-tracking environment has been evaluated and validated by professionals and practitioners from industry using several instruments as described in the paper

Illinois Digital Scholarship: Preserving and Accessing the Digital Past, Present, and Future

Since the University's establishment in 1867, its scholarly output has been issued primarily in print, and the University Library and Archives have been readily able to collect, preserve, and to provide access to that output. Today, technological, economic, political and social forces are buffeting all means of scholarly communication. Scholars, academic institutions and publishers are engaged in debate about the impact of digital scholarship and open access publishing on the promotion and tenure process. The upsurge in digital scholarship affects many aspects of the academic enterprise, including how we record, evaluate, preserve, organize and disseminate scholarly work. The result has left the Library with no ready means by which to archive digitally produced publications, reports, presentations, and learning objects, much of which cannot be adequately represented in print form. In this incredibly fluid environment of digital scholarship, the critical question of how we will collect, preserve, and manage access to this important part of the University scholarly record demands a rational and forward-looking plan - one that includes perspectives from diverse scholarly disciplines, incorporates significant research breakthroughs in information science and computer science, and makes effective projections for future integration within the Library and computing services as a part of the campus infrastructure.Prepared jointly by the University of Illinois Library and CITES at the University of Illinois at Urbana-Champaig

An Experiment in Model Driven Architecture for e-Enterprise Systems

OMG's Model Driven Architecture demonstrates how a system's specification model can be used within the process of creating supporting software implementations. This article documents the findings of an experiment aimed at determining the extent to which this method of software engineering can be used within the domain of e-Enterprise systems

Towards an aspect weaving BPEL engine

This position paper proposes the use of dynamic aspects and the visitor design pattern to obtain a highly configurable and extensible BPEL engine. Using these two techniques, the core of this infrastructural software can be customised to meet new requirements and add features such as debugging, execution monitoring, or changing to another Web Service selection policy. Additionally, it can easily be extended to cope with customer-specific BPEL extensions. We propose the use of dynamic aspects not only on the engine itself but also on the workflow in order to tackle the problems of Web Service hot deployment and hot fixes to long running processes. In this way, composing aWeb Service "on-the-fly" means weaving its choreography interface into the workflow