Docstoc

Introduction The Virtual Classroom

Document Sample
Introduction The Virtual Classroom Powered By Docstoc
					 ECE GRADUATE PROGRAM
                                                                                           Newsletter Date
                                                                                             April 14, 2010

 VIDEOCONFERENCE-BASED
 DISTANCE LEARNING
 Contact: Dr. Herb Kaufman hkaufman@uwindsor.ca, 519-253-3000 x2567
          Dr. M.A. Sid-Ahmed ahmed@uwindsor.ca,   519-253-3000 x2570


 Introduction
 The University of Windsor ECE Dept. is developing      Committee Members:
 the means to deliver Graduate courses online.
 Students from anywhere in the world can earn a         Dr. Xiang Chen, Chair
 graduate degree.                                       Dr. Narayan Kar
                                                        Dr. Roberto Muscedere
                                                        Dr. Rashid Rashidzadeh
 The type of course delivery system we have
                                                        Dr. Herb Kaufman
 envisioned goes beyond the traditional approach
 that offers basically only online notes in
 Powerpoint form. We propose a more dynamic
 version of online course delivery. To this end we
 have adopted the Virtual Classroom model.
 Students will participate in a “live” lecture
 delivered online, as well as having access to
 course resources such as notes and assignments
 through the existing CLEW system.
                                                       through which students and professor can
                                                       communicate in text message form.

The Virtual Classroom                                  It is also desirable to have a way for the professor
                                                       to handwrite notes in a “whiteboard” window.
Requirements:
                                                       A way of recording what was on the screen during
A student with a high-speed internet connection,       the lecture and the professor’s narration is also
anywhere in the world who has obtained valid           desirable.
login credentials by registering can participate.
                                                       The virtual classroom should allow for a quality
The system should be web-browser based and             learning experience, with student participation
work with any type of computer (PC, MAC, Linux,        (students asking questions and getting answers).
Unix) and support most web browsers.
                                                            Note: We presently have a
The professor and students login at the scheduled
time for the class. The professor delivers the              very workable solution to
lecture with slides presented online, which are             these requirements, but
narrated with an audio stream that can be heard             need to fill the reader in on
by the students.
                                                            the background of how we
There should be also a “Text Chat” window                   got to where we are.
Page 2                 ECE Videoconference-based distance learning

Setting Up a Virtual Classroom
Given these requirements we began researching          RHUB Device- We found that a hardware-based
the best way to meet them.                             solution to the streaming problem was available
                                                       from a company called RHUB. RHUB devices
We decided that Adobe Flash was the technology
                                                       could be purchased to stream lectures online
that could work on any browser and any
                                                       without worrying about the bandwidth.
computer, and began investigating and working
                                                       Depending on how many users you wanted to
on Flash-based approaches:
                                                       support, you could buy a hub for $7000 -
Commercially available “turnkey” approaches-           $20000. The main problem with this is that the
At the time we began this project there were some      last time we checked they did not support
commercially available software packages for what      streaming the audio component.
we were trying to do. (Recently the situation has
                                                       Open Source Video Conferencing Projects-
changed with more being available). These
                                                       Meanwhile, others had begun trying to develop
packages, for the most part were primarily
                                                       video conferencing software using the open
designed for video conferencing, rather than
                                                       source Red5 Flash Media Server, as we were,
educational use. There were complicated
                                                       and apparently were making significant
constraints on licensing with costs that escalated
                                                       progress. There was a project called DIMDIM
unfavorably for a larger number of users. It was
                                                       that was available in both open source and
difficult to assess the overall and long-term costs,
                                                       commercial versions. The open source version
due to hidden cost factors. There was also the
                                                       had restrictions on features (at the time) and
issue of sustainability –would the same product
                                                       was extremely difficult to install. Google
continue to be supported in the future?.
                                                       sponsored two open source projects based on
Media Streaming with Flash Media Server (FMS)-         Red5, with software development teams and
Video is streamed over the internet from a video       contributions from the worldwide open source
capture driver software package, which acts as a       developer community. One called
virtual camera. We found that this could be done       OpenMeetings initially showed much promise.
economically with open source components.              We installed various versions of it for testing.
Someone who was frustrated with the high cost of       We worked on the code to modify the interfaces
an Adobe Flash Server had written an open source       from videoconference to a classroom model.
alternative called “Red5”. A freeware video capture    Unfortunately, the software was plagued with
driver from Hmelyoff Labs called VHCapture was         bugs and presented many other difficulties.
found that could work with this. We wrote              Another Google open-source project called
software in FLASH CS3 in Actionscript 3.0 that         BigBlueButton was specifically oriented towards
accomplished streaming of what the professor           classroom (educational) use. It found a way to
sees on his computer monitor (desktop) to the          deal with the bandwidth difficulties by
students, together with audio. A text-chat window      converting each slide to an Adobe .swf file.
was also added. The main problem with this             (Slides were received by the client with no
approach is that it was extremely bandwidth            quality loss.) At that time we abandoned the use
intensive, and had issues with maintaining video       of this software due to limitations in ways of
quality.                                               audio delivery (at that time) and difficulty
                                                       working with their source code.
         ECE Videoconference-based distance learning                                                    Page 3

Setting Up a Virtual Classroom - Continued-
Our Own Custom Written Software- We decided that             one selected student. The way it is configured, an
with all the time we spent fixing bugs in other              audio feed from only one selected student can be
people’s code, we could write our own software. We           enabled by the instructor. We have a number of
improved our software using what we had learned              problems to deal with using this approach. First of
from the other projects. We foresaw that we might            all, one machine must run all of these: Apache file
end up using commercial software, but thought it             server, Red5 real-time video streaming server, and a
would be good to have our own software to fall back          MySQL database server. What if dozens of students
on, in the worst case. We obtained an open-source            are trying to download the typically 900MB files
“front-end” to handle user login and getting directed        from recording a lecture at the same time virtual
to a Flash-based classroom from Sourceforge. It was          classrooms are running in real-time video? Also, we
written in php and ran on an Apache server. It was           are not able to write the code for re-sizable
software primarily written for course scheduling and         windows. It is very difficult to test this software, and
worked with a MySQL database. This software did not          the login section still needs work. Php now has a
fully deal with the authentication issue, as students        memory leak problem and ways of re-writing the
were allowed to self-register. (This is an area that         code to deal with this must be found. The
still needs work.) The courses must be scheduled for         installation of this software is extremely difficult and
the exact days that they run by an administrator who         requires finding compatible versions of php, Apache
logs into the administration part of the software to         and MySQL. The security issues must be analyzed
do this. The software has a “Course Files” section           and dealt with. For example our html command
where the instructor uploads slides (must be pdf.)           parameters are exposed in the URL line and a
ahead of time. Also the recorded lectures in .flv            student editing these could get into a classroom he
format are available for download there. The                 is not allowed into. The software is designed for
software has a slide presentation window, a                  Windows, which is very resource intensive for server
whiteboard window, a text chat window, and a                 hardware.
webcam window that can show the instructor and



 The Present Solution
                                                              Wikis on how to develop the software and build code
 Presently, the BigBlueButton project from
                                                              as well as how to install and run the code on a server.
 www.googlecode,com has made great strides forward.
                                                              There is also a lot of information for the software user
 The code has been improved, the bugs have been
                                                              –how-to-use videos and FAQ’s. The software is based
 worked out and the audio issue is resolved. Some
                                                              entirely on open-source components (including Red5).
 features (e.g. whiteboard) are still lacking, but we have
                                                              It can be installed on a server running Linux Ubuntu
 produced our own modified version of the software to
                                                              9.04 or CentOS. Installation can be done automatically
 deal with this. This software has the advantage that it
                                                              using packages. It runs an Apache Tomcat applet
 is stable and known to work and has been used by
                                                              server, an nginx application server, Red5 server and
 hundreds of people. (See the www.bigbluebutton.org
                                                              (for now) a MySQL database server). There are various
 demo site.) It has been tested by people all over the
                                                              sample login API’s that have been provided that can
 world. The project has a website with the open source
                                                              be modified for specific use. (We have done this.)
 code,
Page 4                ECE Videoconference-based distance learning


The Present Solution -Continued
   Here we see the basic screen layout:
   Note: Our modified version of the software has whiteboard drawing tools
   that appear at the bottom of the presentation window.
   ECE Videoconference-based distance learning                                               Page 5


ROLES:

There are three different roles for participants: viewer, moderator and presenter

Viewer: users who have no authority within the conference; their primary role is to view the
presentation as well as chat (text/voice) amongst other participants. In a course the viewers would be
the students. Can also appear in own webcam window and can have voice input.

Moderator: has all the capabilities as a participant, with the added features of uploading
presentations and sharing their desktop. (Only instructors will be moderators)

Presenter: has all the same capabilities as a participant, with the added features of uploading
presentations and sharing their desktop. ( A moderator can temporarily make a viewer (student) the
presenter –useful for students presentations).

-------------------------------------------------------------------------------------
---
Page 6   ECE Videoconference-based distance learning
ECE Videoconference-based distance learning   Page 7




  The WHITEBOARD

  -displayed in the presentation
  window

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:6
posted:3/10/2012
language:
pages:7