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MLB as an Access Grid node service
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Overview

Multimedia Lecture Board (MLB) is a sophisticated shared whiteboard - a full description is available at the MLB home page. At the time of writing, MLB version 1.1 is available for Linux and Windows environments.

This page describes how to use MLB as an Access Grid node service from within an access grid session. This means that an MLB instance is invoked every time a new room is entered - a whiteboard equivalent of the video & audio services.



Downloads

For Linux systems, download
    MLBService.zip for Linux

For Windows systems, download
    MLBService.zip for Windows


N.B. the MLBService downloads above already contain the appropriate versions of MLB; there is no need to separately download MLB itself. If you want the original MLB anyway, versions are available from the MLB home site as follows:
MLB for Linux
MLB for Windows



Method

Linux:
- depending on how your AG toolkit is installed, you may need to be root user to perform the installation

Copy the Linux MLBService.zip file to the directory /etc/AccessGrid/NodeServices


Windows:
 Copy the Windows MLBService.zip file to the directory c:\Program Files\AGTk-2.3\NodeServices


Usage:
From the VenueClient, select Preferences->Manage My Node. In the management gui which appears, select a ServiceManager (or add one); it should probably be the Service Manager which runs on the machine that the operator is using i.e. display machine. Now select Service->Add and choose MLBService from the list of available services. Whenever a room is entered, a new instance of MLB is created (or any already running MLBService instance is joined).

Start a new shared page from the "Documents" area on the left hand side of the MLB window by clicking on the "new Page" icon.


Gotchas:
  1. (Windows only) drawing activity at the initiating MLB instance is slow to propogate to instances at other sites which have joined (rather than started) the MLB session.
  2. There is an AG toolkit bug, which results in an incorrect extraction of this service (and some others). There is a fix in CVS which hasn't reached the general release packages yet (May 2005). Download the fixed file (Types.py), or retrieve it from CVS, and copy it to
    • for Linux, to directory /usr/lib/python2.4/site-packages/AccessGrid/
    • for Windows, to directory c:\Python23\Lib\site-packages\AccessGrid\


Acknowledgements

Universities of Mannheim and Freiburg for Media Lecture Board
Funding through UQVislab, QPSF and APAC Collaborative Services Group


Any comments, suggestions to Chris Willing <willing at itee.uq.edu.au>