Gary J. Hill

Towards an integrated information environment with open hypermedia systems

This paper examines open hypermedia systems and presents the case that such systems provide a step forward for dealing with large, dynamic data sets in distributed, heterogeneous environments by allowing users to access and integrate information and processes in richer and more diverse ways than has previously been possible. In particular, the enhanced Microcosm model for open hypermedia is examined, and the ways in which it provides such an environment are discussed. The paper continues by investigating the advantages and the shortcomings of this model and identifies the areas in which further work must be completed before such systems can become widely adopted, such as the granularity of source and destination anchors, editing and version control. Some attempts to provide solutions to these problems are presented and discussed.

A distributed hypermedia link service

Open hypermedia is an established model within the hypermedia research community; it provides an approach to engineering flexible and maintainable hypermedia systems based on the concept of a hypermedia link service. However the World Wide Web, which provides an important solution for distributed hypermedia, is typically used as a closed hypermedia system: it does not exploit the link service concept. This paper presents the design of a system which applies the open hypermedia philosophy to the World Wide Web, whereby the link service component is abstracted out into a third party service known as the distributed link service (DLS). A scalable architecture for the DLS is discussed and experience with a prototype is described.

Extending the microcosm model to a distributed environment

In recent years, there has been significant growth in the use of computer networks to support electronic delivery of information. As the volume of available information has grown, a need for powerful tools that can manage access has arisen. It has been suggested that hypertext techniques can provide such a facility. The Microcosm system is a hypertext link service developed at the University of Southampton. The system is based upon a modular architecture which allows the functionality of the system to be easily and dynamically extended. This paper describes the development of a distributed version of Microcosm based upon this modular design. The distributed system described utilises the fine granularity of the Microcosm model to support a wide range of wide possible configurations. The system also extends the document management facilities of Microcosm to allow information stored by other information services to be incorporated. The result is a system that can apply Microcosms open linking services to a wide range of networked information.

MEMOIR — an open framework for enhanced navigation of distributed information

In large companies, whose business is critically dependent on the eAectiveness of their R&D function, the provision of eAective means to access and share all forms of technical information is an acute problem. It is often easier to repeat an activity than it is to determine whether work has been carried out before. In this paper we present experiences in implementing and evaluating the MEMOIR system. MEMOIR is an open framework, i.e., it is extensible and adaptable to an organization’s infrastructure and applications, and it provides its user interface via standard Web browsers. It uses trails, open hypermedia link services and a set of software agents to assist users in accessing and navigating vast amounts of information in Intranet environments. Additionally, MEMOIR exploits trail data to support users in finding colleagues with similar interests. The MEMOIR system has been installed and evaluated by two end-user organizations. This paper describes the results obtained in this evaluation. 7 2000 Elsevier Science Ltd. All rights reserved.

Implementing an open link service for the World Wide Web

Links are the key element for changing a text into a hypertext, and yet the WWW provides limited linking facilities. Modeled on Open Hypermedia research the Distributed Link Service provides an independent system of link services for the World Wide Web and allows authors to create configurable navigation pathways for collections of WWW resources. This is achieved by adding links to documents as they are delivered from a WWW server, and by allowing the users to choose the sets of links that they will see according to their interests. This paper describes the development of the link service, the facilities that it adds for users of the WWW and its specific use in an Electronic Libraries project.

Open information services

The Distributed Link Service[5] provides hypermedia services, layered on top of, but independent of, the underlying document data services provided by the World Wide Web. This model enables enormous flexibility for providing and manipulating links and designing information architectures, but conversely abandons any guarantee of synchronicity between changes in the data layer and the links layer. This paper contrasts this approach to link management with the more generally accepted (and safer) solution of a closed information environment (perhaps in the form of an object-oriented SGML database), and presents an expanded open hypermedia service for the WWW composed of link management together with document management and consistency maintenance tools.

The microcosm link service

INTRODUCTION As understanding of hypertext concepts has increased, the possibilities they present for the creation of a flexible system able to act as an integrator for a user’s whole environment are growing. This has led to interest in the concept of open hypermedia systems that are able to act as a link service to an existing set of applications. The key to this concept is in the perception of hypertext principles as a method for integration rather than simply as a delivery medium for a clearly defined information set.

An open framework for integrating widely distributed hypermedia resources

The success of the WWW has served as an illustration of how hypermedia can enhance access to large repositories of distributed information. However, current distributed hypermedia systems offer limited hypermedia functionality which cannot easily be augmented or simply applied to existing applications and data formats. This paper describes a model and prototype, based on the Microcosm system, of a reflexive and extensible distributed hypermedia framework for managing hypermedia application development, sharing and re-use.

Applying Open Hypertext Principles to the WWW

The concept of an open hypertext environment is now accepted as the best way to provide a flexible and extensible approach to the provision of hypertext functionality. Although very popular, the World Wide Web system created at CERN in Switzerland is a closed system, and suffers a number of drawbacks as a result. This paper describes how an open hypertext approach may benefit users and authors of World Wide Web material, and illustrates how the World Wide Web may be extended to provide a more open hypertext model.

An open architecture for supporting collaboration on the Web

The MEMOIR framework supports researchers working with a vast quantity of distributed information, by assisting them in finding both relevant documents and researchers with related interests. It is an open architecture based on the existing Web infrastructure. Key to the architecture are the use of proxies and the use of an open and extensible message protocol for communication: to support message routing for dynamic reconfiguration and extension of the system, to collect information about the trail of documents that a user visits, and to insert links on-the-fly. We present the MEMOIR architecture and its rationale, and discuss early experiences with the system.