Christian Och

Integrating infrastructure: enabling large-scale client integration

The open hypermedia community has addressed issues of client integration—providing hypermedia services in thirdparty applications—over the past decade. As a result, a set of models and techniques has emerged to guide developers in the task of integrating hypermedia services into their applications. We argue that the logical next step for the open hypermedia community is to develop techniques for integrating massive numbers of clients in tandem. Our approach consists of integrating existing infrastructure mechanisms that are already used by numerous applications. We believe that integrating an underlying infrastructure can provide a basic level of hypermedia functionality to client applications while reducing the level of effort required of application developers. We present issues encountered in performing client-integration-in-the-large, discuss an experimental prototype of a specific infrastructure integration, and describe related work in this area.

Integrating heterogeneous data sources using the COIL mediator definition langauge

Megaprogramming, module interconnection languages, and mediator-based approaches built on standard distributed object technologies such as CORBA and DCOM have provided promising advances in enterprise-level data integration. These distributed object technologies, however, still require relatively low-level, technology-dependent implementations to achieve object (or module) interconnection, communication, and coordination. The Component Object Interconnection Language (COIL) is a language designed specifically to facilitate rapid and flexible data integration through high-level object interconnections. COIL is an extensible language, with both declarative and imperative aspects. It has been designed to provide broad functionality in declaring and controlling structural and semantic data integration, and includes constructs for specifying updates, constraint enforcement, and update propagations. This paper presents an overview of COIL and a stylized example showing an application of the COIL language and its components.

Building mediators from components

Mediators as an integral part of a distributed database environment are not a new idea. However, mediators are often looked at from the outside. The goal of the Sanctuary project is to provide an environment that allows one to configure the internal components of a mediator in a quick and modular fashion that allows the power and breadth of a CORBA facility. The Common Object Interconnection Language (COIL) is a programming language in development by the Database Research Group at the University of Colorado that allows fine grained specification of components within a mediator. COIL is the language that is used to specify mediators within the Sanctuary data mediation run-time system.

Programmable ubiquitous telerobotic devices

We are investigating a field of research that we call ubiquitous telepresence, which involves the design and implementation of low-cost robotic devices that can be programmed and operated from anywhere on the Internet. These devices, which we call ubots, can be used for academic purposes (e.g., a biologist could remote conduct a population survey), commercial purposes (e.g., a house could be shown remotely by a real-estate agent), and for recreation and education (e.g., someone could tour a museum remotely). We anticipate that such devices will become increasingly common due to recent changes in hardware and software technology. In particular, current hardware technology enables such devices to be constructed very cheaply (less than

An Overview of Souk Nets: A Component-Based Paradigm for Data Source Integration

500), and current software and network technology allows highly portable code to be written and downloaded across the Internet. In this paper, we present our prototype system architecture, and the ubot implementation we have constructed based on it. The hardware technology we use is the handy board, a 6811-based controller board with digital and analog inputs and outputs. Our software includes a network layer based on TCP/IP and software layers written in Java. Our software enables users across the Internet to program the behavior of the vehicle and to receive image feedback from a camera mounted on it.

The COIL data mediator definition language

Construction of complex software systems with off-the-shelf components has become a reality. Component-based frameworks tailored specifically for the domain of database integration are lacking, however. To use an existing component framework, data integrators must construct custom components specialized to the tasks of the data integration problem at hand. This approach allows other components provided by the framework to be reused, but is overly tedious and requires the integrator to employ the programming paradigms assumed by the component framework for interconnection and intercommunication between components, and manipulation of data provided by them. An alternate approach would employ a framework containing components tailored to data integration and which allows them to be interconnected using programming methods that are more natural to the domain of data integration. Souk is a language-independent, component-based paradigm for data integration. It is designed to allow the rapid construction of data integration solutions from off-the-shelf components, and to allow flexible evolution. This paper gives an overview of this paradigm.

Sybil: Supporting Heterogeneous Database Interoperability with Lightweight Alliance.

Modern persistent applications typically run on top of numerous (often hundreds) of distributed, heterogeneous databases. Integrating data from various data sources in order to provide uniform, homogeneous, and consistent access to the data from the underlying data sources while preserving the integrity and autonomy of preexisting data sources is a huge problem, especially in evolving environments. The main issue that a global information sharing system has to address is heterogeneity on all levels of the participating data sources: the data might be stored in heterogeneous data sources, using different data models and access/middleware technologies. Another major type of heterogeneity that has to be addressed by a global information sharing system is due to differences in the semantics of the data from the data source participating in the integration process. In particular, the resolution of potential conflicts due to structural and semantic heterogeneity of the integrated data is an essential part of the integration process performed by a data integration environment.