INTRODUCTION

Congratulations ! You have discovered one of the most versatile object frameworks for distributed control and monitoring application.

World Wide Lab ^TM  is designed to simplify the construction of complex control and monitoring systems that spans local and wide area networks. It allows the users to build a distributed system using "drag-and-drop" type of visual programming methods. At the same time, it provides a standard library for the users to customize their application using traditional programming techniques.

Typical Word Wide Lab applications include

• Teleoperation for remote experiments (NASA Payloads, robotics telescope, etc.)

• Integrated plant monitoring and control (factory, power plants, etc.)

• Building security

FEATURES

Because it is based on Java language environment, World Wide Lab ^TM offers all the benefits of Java. These includes open-standard, platform-independence, object serialization, universal database connectivity (JDBC), multimedia (JMF), etc.

More importantly, World Wide Lab ^TM provides the abstraction layer for a "white board" message-passing distributed computing architecture. There are three major entities under this framework:

1. White Board  (WB)
2. Data Publisher (DP)
3. Data Subscriber (DS)

A WB contained many Subjects which are defined by DPs. The messages passed from a DP to DSs are associated with an unique Subject. Message can be Simple or Composite. A Simple Message contains one object such as Double, String, Integer. A Composite Message contains a serialized collection of objects.

 
 
The following events take place in a typical message passing operation between a DP and a DS:

1. DP defines a Subject S on WB.
2. DS subscribes to Subject S on WB.
3. DP publishes a message related to Subject S on WB.
4. WB forwards the message to all DS who subscribe to Subject S.

TARGET AUDIENCE

The user is assumed to be a software engineer familiar with

• Java programming
• HTTP server setup
• Configurations for distributing Java Applets

If not, LIS Technologies (support@listek.com) can provide training and support for the above tasks for a reasonable fee.
 

SYSTEM REQUIREMENTS

Any computer that runs JDK 1.1