eLib Technical Issues Concertation Day:

Mobile Code and VRML Brian KellyUK Web FocusUKOLN, University of Bath, BathB.Kelly@ukoln.ac.ukhttp://www.ukoln.ac.uk/

Contents

Mobile Code• CGI• Java• ActiveX

VRMLIssues

Mobile CodeCGI Model

• Common Gateway Interface• Run software on server• Output (virtual or dynamic document) delivered to

clientMobile Code

• Download code from server and run on client computer

• Examples include Java and SafeTCL• Security is a big issue

JavaJava is Sun’s implementation of mobile code:• Security built-in (runs

on virtual machine)• Support from major

manufacturers (Sun, Netscape, Microsoft, IBM, …)

• Not for the novice programmer

http://java.sun.com:81/nav/used/metamedia.html?

ActiveXActiveX is Microsoft’s implementation of mobile code:• A framework for

integration, not a programming language

• Developed from Microsoft’s OLE desktop model

• Security based on digital signatures

http://www.microsoft.com/activex/gallery/

ActiveX ExampleActiveX contols can be written in Java.Here the Future-Tense Texture ActiveX control gives contol over the layout, as well as restricting access to the document source

http://www.futuretense.com/texture/gallery/Gazette/Gazette.html

VRMLVRML:

• Virtual Reality Model(l)ing Language• Brings 3D worlds to WWW

VRML specifications:• VRML 1.0 -Simple spec, produced quickly. Based on SG Inventor • VRML 2.0 - Provides interaction • Voting on VRML 2.0 proposals, followed by agreement

VRML Example

VRML browsers are now bundled in with Netscape and Microsoft Explorer browsers

Further InformationJava

• http://java.sun.com/• http://www.jars.com/• http://www.gamelan.com/

ActiveX• http://www.microsoft.com/activex/• http://www.activex.com/

VRML• http://vrml.wired.com/• http://www.sdsc.edu/vrml/

See also resources athttp://www.yahoo.com/

Issues

Issues which WWW developers will have to address include:

• Is VRML relevant to my project?• Which architecture of mobile code to

use?• Deployment of new features (e.g. Java

support, VRML support)