© Copyright 2006 Texas Digital Library. All Rights Reserved.
Vol 1, No 2 (1997)
Editorials
Articles
A Vision for Open Hypermedia Systems
Currently, the Open Hypermedia Systems (OHS) Working Group claims three main areas of interest: scenarios, reference architectures, and protocols. The discussions over scenarios of OHS use are supposed to inform the work on OHS reference architectures, which in turn is supposed to enable the development of an Open Hypermedia Protocol (OHP) that will allow clients of one OHP-compliant OHS to use services of other OHP-compliant OHS's. In this paper, we start from existing proposals for an OHS reference architecture and an OHP. We then present a number of scenarios that motivate modifications to these existing proposals. These modifications primarily include adding the notion of an open structure processing layer to the reference architecture and adding a fixed minimal set of guaranteed services to the protocol. We then present our resultant reference architecture and protocol proposals. Our proposals are based on current working group proposals, but incorporate the modifications suggested by our scenarios. Finally, we conclude with some comments on the process we used to derive our proposals, an evaluation of current progress of the OHS Working Group, and suggestions for future directions.
View full text: ZIP Archive
Towards a Common Reference Architecture for Open Hypermedia
This paper contributes to an ongoing effort on standardizing open hypermedia system architectures and communication interfaces. Open hypermedia systems share the property of being able to provide non-hypermedia applications with hypermedia structuring and navigation capabilities. This support is currently provided in many different ways. To be able to standardize communication interfaces, it is necessary to develop common understanding of the different architectures of existing systems and to develop a common reference architecture for open hypermedia systems. A reference architecture should provide a common language for the design of open hypermedia systems in terms of architectural elements and interfaces. The paper identifies a number of important requirements and characteristics for open hypermedia systems and examines some of the most well known open hypermedia architectures and reference models. The analysis illuminates the commonalties and differences in terminology and architectural elements. The analytical results are used to propose common terminology and a common reference architecture for open hypermedia systems (CoReArc). CoReArc identifies several different architectural elements and communication interfaces for potential interface standardization. Interface standardization may be achieved through a single physical protocol with several suites or topics or through several independent protocols. CoReArc can be used to identify and discuss the different communication interfaces of an open hypermedia system.
View full text: HTML
OHRA: Towards an Open Hypermedia Reference Architecture and a Migration Path for Existing Systems
The open hypermedia research community recognised that to make progress on defining a protocol to enable third party applications to access open link services, it was necessary to first establish a reference architecture for open hypermedia systems upon which to base discussions. In this paper we argue that there is a need to extend yet further the scope of these requirements. We propose an overall architecture for the integration of existing open hypermedia systems in a distributed and collaborative model, and provide a clear evolution path towards achieving this goal.
View full text: HTML
A Critique of the Open Hypermedia Protocol
The Open Hypermedia Protocol is a proposed standard for enabling the interoperability of client applications with open hypermedia systems. This paper presents the protocol at a high-level of detail, performs an analysis of its strengths and weaknesses, and makes specific recommendations for improvements to the protocol. In addition, the paper records how a new version of the protocol is evolving. The arguments and recommendations of this paper are based on the information presented in [1] and [29] as well as the results of the discussions held on the protocol at the following events: the Second International Workshop on Open Hypermedia Systems (OHS 2.0), the December 1996 Open Hypermedia Working Group Meeting (OHS 2.5), the Third International Workshop on Open Hypermedia Systems (OHS 3.0), and the September 1997 Open Hypermedia Working Group Meeting (OHS 3.5).
View full text: HTML