Australian Subject Gateways Forum

Definitions for Web-Based Services

A set of working definitions for Web-based services linking to high quality, reviewed resources for researchers and other interested parties.

These definitions, recently revised by the Australian Subject Gateways Forum (ASGF) working group, were endorsed at the ASGF meeting on 23rd February 2001.

They are provided as a guide only, to assist discussion and act as a reference point for creators of these types of services. In assessing the usefulness of these definitions, it is necessary to consider what the services will become.

Suggestions for additions or updates are welcome - please contact the Library at: csb@nla.gov.au

Types of Services

The research undertaken when reviewing this web page revealed a range of terms that refer to similar conceptualised services: subject gateways, subject-based resource discovery systems, Internet resource guide, information gateways, hybrid libraries, virtual libraries, and SINs - Special Interest Networks. These are just a few of the synonyms used on the Internet to describe similar services.

Six types are suggested for discussion (others may need to be added):

WWW Virtual Library

An early Web concept which reflects the scope of thinking in the mid 1990s, before the existence of standard metadata schemas for resource discovery. It was intended as an online catalogue of Web resources. Good examples still exist, such as the Australian Biological Research Network (also known as a Special Interest Network), and the Aboriginal Studies WWW Virtual Library.

Top

Clearinghouse

Contains computer-based education resources, with reviews, and links to related material. One particular clearinghouse service was funded by the Australian Committee for University Teaching and Staff Development. However CUTSD Coordinating Centre has been closed. There does not seem to be any value in rescuing the resources contained in each centre, as they are mostly out-of-date. This type of service may be superseded by IMS (IMS Global Learning Consortium Inc.)

Top

Subject Gateway

A subject gateway has been defined by the Australian Subject Gateways Forum as: "a Web-based mechanism for accessing a collection of high quality, evaluated resources identified to support research in a particular subject discipline". It is a service which is accessed via a portal, through open standard protocols (such as Whois++, LDAP, Z39.50, Harvest Broker) which allow it to slot in seamlessly behind the scenes. What the end-user sees is Web-based, behind the scenes is more structured.

A simple definition of a subject gateway is:

"An Internet accessible collection of descriptions and location details for a range of information, generally available electronically, organised by subject or discipline, and selected for inclusion based on a published set of quality criteria."

The IMesh Toolkit project provides the following definition:

"A subject gateway is a web site that provides searchable and browsable access to online resources focused around a specific subject. Subject gateway resource descriptions are usually created manually rather than being generated via an automated process. Because the resource entries are generated by hand they are usually superior to those available from a conventional web search engine." Reference: IMesh Toolkit: What is a subject gateway?.

A further description of subject gateways as promoted by the DESIRE Project, funded by the European Commission, is:

"Selective subject gateways on the Internet are characterised by their quality control. The core activities of resource selection and description rely on skilled human input (by librarians, academics and experts) and are not activities that lend themselves to automation." Reference: Selection Criteria for Quality Controlled Information Gateways, Work Package 3 of Telematics for Research project.

To summarise, subject gateways display the following typical characteristics (based on Reference: Traugott Koch Quality-controlled subject gateways: definitions, typologies, empirical overview) (http://www.lub.lu.se/~traugott/OIR-SBIG.txt):

1. Resource Selection
A human intermediary adds value by selecting appropriate Internet resources, usually according to rigid selection criteria. Resources are usually selected for their quality, authority, accessibility, currency and subject relevance. Other selection criteria may also apply such as language or geographic coverage.
2. Collection Maintenance
Regular maintenance of the collection occurs, including the removal of resources that are no longer appropriate, are superseded or contain data entry errors. Regular link checks may also be carried out. These procedures may be automated or carried out manually through human intervention. A policy will exist that details these procedures.
3. Resource Description
Selected resources are annotated by a human intermediary with a full description of the resource. The descriptions will be entered according to a predefined, structured metadata schema. The metadata is structured into separate fields. This enables the resource to be easily identified and located. It also facilitates structured searching. The descriptions may contain information about the content, author, publisher or publication date of the resource.
4. Subject Classification
A human intermediary uses a subject classification schema to index all resources. This facilitate subject browsing.

Subject gateways are also often characterised by application of standards to allow interoperability with other services, and various value-adding features.

Top

Gateway

This term is used by the Resource Discovery Network in the UK as the preferred term for subject gateways. It is a generic term that is sometimes used interchangeably with the term subject gateway. The term is used to describe a "range of Internet sites that in some way provide access to other, predominantly Internet-accessible, resources." Reference: Renardus: Gateways Defined. Renardus also distinguishes between 'gateways', 'subject gateways' and 'quality-controlled subject gateways'.

Top

Portal

"In the library community, [portals] may be defined as an amalgamation of services to the patron where the amalgamation is achieved through seamless integration of existing services by using binding agents such as customisation and authentication services, search protocols such as Z39.50, loan protocols such as ISO10161, and e-commerce. The result is a personalised service which allows the individual to access the rich content of both print-based and electronic systems." Reference: Debbie Campbell Australian Subject Gateways - Metadata as an Agent of Change.

An addition to the portal definition:
End-users can also specify options which will push selected content to them on a pre-agreed basis.

Portals (also sometimes called Megaportals, Horizontal Enterprise Portals or HEPs ) differ from vortals in that they provide a broad range of services and content to a diverse range of customers. They do not seek to target their services to a particular demographic group, industry or topical category. They can therefore be characterised as "horizontal" in scope as opposed to "vertical". They offer at least five features, including: web searching, news, reference tools, access to online shopping, and some communication capabilities such as free e-mail and chat. Reference: The Australian, Tuesday February 1, 2000, p.2.

Top

Vortal

Vertical portals or vortals are different in the range of users they target. Vortals provide content aggregation relevant to their industry, with links to related industry, supplier and even competitor sites. They may have community and collaboration capabilities, and e-commerce services for products and services relevant to its industry or niche. Vertical portals also try to leverage branding and associated technologies in a focused way.Reference: The Australian, February 1, 2000, p.2.

Top

Internet Resource Catalogue

A database of Internet resource descriptions that is made accessible through a structured and/or unstructured network service. Sometimes used synonymously with 'portal' and 'gateway' (eg by by the Resource Discovery Network [2007: now InTute]). An Internet Resource Catalogue may be just one of the services offered by a gateway or portal.

Top

Document History

Debbie Campbell, NLA, dcampbell@nla.gov.au
Initial Draft: February 2000
Addition to Draft: March 2000 (inclusion of definition of commercial portals)
Addition to Draft: June 2000 (inclusion of definition of Internet Resource Catalogues)
Revision: February 2001 by Nicole Van Kempen, Louise Arkles and Barbara Rozmus
Update: February 2003 by Barbara Rozmus
Update(links checked): October 2007 by Sandra Henderson

Date last verified: 16 October 2007

About This Site | Copyright | Privacy | Accessibility | Site Map | Site Search | Content A-Z | Contact Us