We have developed a technique for providing an instant messaging and presence (IMP) middleware that allows IMP protocol implementations to be dynamically loaded as a client application roams among various service provider networks with different IMP services. This technique addresses the problem of maintaining IMP sessions while roaming between domains with different IMP protocols. We describe the mechanism, relate it to network handoff mechanisms, and analyze a prototype implementation.

The paper outlines an approach toward extending the OSGi (open services gateway initiative) framework to support interoperability with mobile devices. The approach is based on the use of SIP (session initiation protocol), which is likely to be employed by next-generation mobile networks. The extensions to OSGi allow a SIP device to participate in an OSGi platform and allow OSGi services to be exported into a mobile (SIP-based) environment. We propose an architecture supporting the integration of SIP with OSGi, provide some application scenarios and describe the details of the SIP Service for OSGi.

This poster presentation describes some possible scenarios illustrating the interaction between digital TV receivers and home networks. These scenarios are based on free implementations of open interactive digital TV (iDTV) platforms (DASE and MHP) and home network platforms (OSGi). A brief comparison of some available platform implementations is given in the presentation. Proposed scenarios include administration of a home network from the screen of an iDTV receiver, delivery of software bundles to an OSGi platform via a data broadcast carousel and interaction between iDTV applications and devices in home networks. Possible scenarios are illustrated by corresponding demonstrations of actual prototypes.

Interactive digital television (IDTV) promises to enhance traditional television programming. Current approaches to IDTV generally use either the primary television display or add a second display that resides on a traditional personal computer. This paper outlines a new approach to IDTV that uses a handheld IDTV device, and describes a working prototype that demonstrates the merit of this type of solution. The approach we describe allows interactive content to be delivered to an individual without impacting other viewers. Further, by targeting small devices, IDTV content can become portable, for "anytime, anywhere" interaction.

Exu is a new approach to automated support for safe, transparent and lightweight interoperability in multilanguage software systems. The approach is safe because it enforces appropriate type compatibility across language boundaries. It is transparent since it shields software developers from the details inherent in low-level language-based interoperability mechanisms. It is lightweight for developers because it eliminates tedious and error-prone coding (e.g., JNI) and lightweight at run-time since it does not unnecessarily incur the performance overhead of distributed, IDL-based approaches. The Exu approach exploits and extends the object-oriented concept of meta-object, encapsulating interoperability implementation in meta-classes so that developers can produce interoperating code by simply using meta-inheritance. An example application of Exu to the development of Java/C++ (i.e., multilanguage) programs illustrates the safety and transparency advantages of the approach. Comparing the performance of the Java/C++ programs produced by Exu to the same set of programs developed using IDL-based approaches provides preliminary evidence of the performance advantages of Exu.

Compiler projects frequently use parser generators to help students design and construct non-trivial translators. Unfortunately, the code and data structures produced by such generators, and hence the overall parser, can be difficult to understand and debug. In this paper, we present an extendible and flexible tool for visualizing the operation of generated parsers. The objective of this tool is to provide students with a deeper understanding of parsing algorithms, data structures and techniques.

No abstract available.

No abstract available.

Interoperability is a fundamental concern in many areas of software engineering, such as software reuse or infrastructures for software development environments. Of particular interest to software engineers are the interoperability problems arising in polylingual software systems. The defining characteristic of polylingual systems is their focus on uniform interaction among a set of components written in two or more different languages.Existing approaches to support for interoperability are inadequate because they lack seamlessness: that is, they generally force software developers to compensate explicitly for the existence of multiple languages or the crossing of language boundaries. In this paper we first discuss some foundations for polylingual interoperability, then review and assess existing approaches. We then outline PolySPIN, an approach in which interoperability can be made transparent and existing systems can be made to interoperate with no visible modifications. We also describe PolySPINner, our prototype implementation of a toolset providing automated support for PolySPIN. We illustrate the advantages of our approach by applying it to an example problem and comparing PolySPIN's ease of use with that of an alternative, CORBA-style approach.

Name management is among the most basic foundations of software engineering, since so many software engineering tools and techniques fundamentally depend upon manipulation of names and the entities that they represent. While many individual tools and techniques have included their own specialized, often elaborate and idiosyncratic, approaches to name management, no unifying models for name management currently exist. As a result, the individual approaches are frequently complex and error-prone, while attempts to integrate collections of software engineering tools or techniques are often impeded by the inconsistency and incompatibility of the name management approaches used in the individual components of the collection. In this paper we consider some examples in which name management problems complicate software engineering activities. In particular, we focus on context control-related problems that often occur during software development. We then outline a unifying model of name manag...