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High-level Design

The Interactive HTML high-level design -- which primarily involves defining extensions to existing WWW standards -- must be very carefully designed in order to meet the key issues of integration and standardization. One of the most important consideration is probably just the number of changes introduced -- the fewer there are, the less impact there is likely to be on either of these issues. This means that each change should be carefully justified, and designed to leverage off of the existing standards as much as possible.

HTML Extensions

Interactive HTML introduces two extensions to existing tags, along with the introduction of a new tag used to support these extensions.

The first extension is to the <LINK> tag, which is now able to incorporate external language modules into the document in which it is used. These modules may include packages for implementing new functionality (such as math libraries, user interface elements, etc.) or include components of a larger program defined by the entire document. The extension provides a means by which the document may request standard libraries, minimum versions, and instruct the browser to retrieve the module from an external source if what is available locally does not meet these requirements. This is intended to provide a path by which new browser functionality may be smoothly incorporated into the Web -- standard modules may be developed privately and then publically made available by individuals within the Web, and gradually be bound closer to the browser as they prove their worth, while still enabling older browsers which do not incorporate them to remain backwards compatible.

A similar change to HTML, but probably more important one, is the addition of similar new attributes to the <FIG> tag, which allows interactive program objects to be embedded in a document, where currently only a static image is allowed. The new tags incorporate the general functionality of the <LINK> tag; a simple tag <PARAM> is also introduced, which may occur only inside of a <FIG> and allows arguments to be supplied to the requested object.

URL Extensions

One new URL is defined by Interactive HTML, tcp:. This URL has the standard base syntax the other URLs such as http: use, i.e. <URL:tcp://{address}:{port}>. This tag is used internally by programs to open interactive TCP/IP connections with servers over a network. For example, the URL to open a connection with a server at the host "python.cs.orst.edu" on port 3000 would be <URL:tcp://python.cs.orst.edu:30000>.

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Dianne Kyra Hackborn <hackbod@angryredplanet.com>
Last modified: Wed Aug 14 16:03:43 PDT 1996

This web page and all material contained herein is Copyright (c) 1997 Dianne Hackborn, unless otherwise noted. All rights reserved.