EDEC: Figure 1. Block Diagram of Delivery, Control and Communication System for EDEC Courseware.
The WWW was chosen as it confers several benefits:
It was also noted that the same framework could eventually support features such as higher security, charging, supply of ancillary material, etc. Therefore, this pragmatic solution to a particular problem has considerable potential for robust generalised electronic distribution.
Browser: The Netscape WWW browser is combined with a custom helper application and the run-time versions of the Authorware and KPWin multimedia packages, using a customised installer. This creates an EDEC Distribution System program group window, containing a Netscape icon. The browser is launched showing the EDEC home page, from which courseware is accessed by hyperlink and a username/password control.
A selected module is transferred as a compressed file to the user s machine, with a special extension that invokes a decompress/install helper application. This temporarily stores the compressed file, decompresses it, deletes the compressed version, copies and runs the installer. The module is loaded into a directory chosen by the user, then an EDEC Courseware program group window is created, and the temporary directory deleted. If any process fails, a dialogue box is generated. The procedures used minimise the possibility of corrupting the user machine configuration.
The 'forms' response enables comments to be returned to the server, and the 'mailto' facility provides feedback to the administrator.
Server: The NCSA HTTPD server provides HTML pages with hyperlinks to public EDEC information, and to courseware through a password access. Response form recording and automatic logging of accesses are provided. These are linked to an Access database, generating reports showing authorised user, title and time for downloaded modules, and other access details.
Modules are uploaded into the server from a remote development ftp site. Runtime files are packaged with dlls and drivers, and put into a directory structured for unique identification. When a module is modified, the old version is archived and the new version substituted. This provides an audit trail.
HTML editing, username/password generation and assignment, database maintenance, and email messaging are carried out on the server.
However, as noted in the introduction, the software used is mainly free issue or shareware, so has known limitations. It would not be difficult, with some additional funding, to produce a fully specified and robust version, incorporating additional features. This would be of benefit to all agencies with computer-aided learning material that requires delivery to dispersed audiences.
EDEC: Figure 1. Block Diagram of Delivery, Control and
Communication System for EDEC Courseware.