eLearning Applications
Video Conferencing
Page last updated 11 January, 2007
Videoconferencing: An Introduction
Video conferencing has been used within higher education for over 15 years, and within the world of business for a while longer. The technology enables people to see and hear each other by using a combination of computer and communication technologies. Users can communicate at a distance, share the same computer-based workspaces and visually collaborate. LEFT: A Videoconference in progress
(Courtesy of PictureTel Corporation) The most common kind of video conference equipment in the UK is desktop (PC) conferencing. This is where a camera sits on top of your desktop pc screen and connects through telephony to other desktop computers with similar equipment attached.
Desktop Video Conference Systems
There are two
kinds of connection currently available. Analogue videoconferencing relies on
modem technology and connects on a dial up basis.
This is a fairly cheap option, as the user needs only to purchase a modem and
video conference kit, which can be as little as £200. One telephone line is
used to make the connection, but the visual images are poor and movement on the
screen at between 1-4 frames each second can appear quite jerky.
Digital networks
such as ISDN provide a higher quality method but are more expensive to use.
ISDN is Integrated Services Digital
Network and is a public network. Normally, two digital lines are used
to give the system enough bandwidth to send moving pictures. ISDN2 will
typically yield around 12-15 frames each second, providing reasonable audio and
video quality.
RIGHT: A desktop videoconference system(Courtesy of PictureTel Corporation)
Sharing Applications
Imagine you have a colleague who is working with you on an important piece of written work. You are both using a wordprocessor on personal computers in your respective offices. Unfortunately, your colleague is 500 miles away in another part of the country, and it is impossible to travel to meet each other regularly. The solution... ...application sharing through video conference. With most videoconference systems, users are able to share the software they are using with a remotely connected site. This means that if you are using Excel spreadsheet XP version, you can share the work stored on this software with your partner, and both of you can move around in the spreadsheet, adding, modifying, saving and printing, whilst you discuss the work.Multi-Point Conferences
There are times when more than two sites wish to communicate together using video conferencing. This can be achieved by the use of a video bridge. Video bridges are specialised systems that enables several video conference sites to dial in together. At a receive site, the user will see their own local picture and a set of pictures showing all the other participating sites. In this kind of situation it is advisable to designate a chair person who can ensure that one site speaks at a time, to avoid confusion!
Room based systems
Another (more expensive) higher quality system is room based or 'roll about' technology. These systems use large monitors and usually more than two digital lines (combinations of 3 or 6 lines are the most common configurations). At the University of Plymouth, room based video conferencing has been implemented on an ISDN 6-12 line equivalent system. LEFT: A room-based videconference system(Courtesy of PictureTel Corporation) This provides enough bandwidth for 'full motion' pictures at between 25-50 frames each second.
Current Uses
At the University
of Plymouth video conferencing is used regularly for teaching sessions,
seminars, meetings, conferences and research. Each of the main University sites
are equipped with room based video systems, and there are also several desk top
pc video conference systems in place in key offices across the campuses.
Video conferencing is set to save teaching staff a great deal of time which
would have been taken up travelling by rail or road from one site to another.
Combining Video Conference and Satellite TV
The University is using a combination of digital satellite television and video conferencing to connect its dispersed student groups around the region. Videoconferencing technology can be used to enable remote students to call back into the studio whilst a live programme is on air and ask questions of the guests and experts (See the diagram above). This technique has been successfully used in the last few years in many of the university's live TV transmissions. With increased bandwidth and greater transmission speeds now becoming available, it will not be long before academics in any part of the university will be able to enter their local videoconference suite and broadcast a live programme to anywhere in the world. A very useful resource for those wishing to better understand videoconferencing can be found in the online paper by Lynne CoventryThe Future of Video Conferencing
Several commercial companies are developing new ways of using video
conferencing in education. One of the most recent developments is to
incorporate video conferencing into web based systems.
A web based system using
streaming video multi-casting is now reaching the education sector.
Teachers and presenters can sit in their own office or in a nearby studio and
present a 'live' lecture in front of a camera attached to a web server. Using a
simple switching device and several cameras, the presenter can provide remote
participants with graphics, whiteboard, flipchart and other visual aids as well
as alternative views of the local classroom, lecture room, etc.
These images and sound are subsequently
webcast - sent via the Internet to anyone who wishes to take part.
Alongside the video images and sound is a MS Powerpoint presentation or other
graphical sequence transmitted in a .gif file format. Synchronising software
enables the graphic images and presentation materials to reach the viewers at
the same time the presenter verbally cues them.
Beneath the tutor's video images is a text messaging box where students and
participants can offer comments, ask questions, and receive responses from the
presenter in real time. Research has shown that remote students are more likely
to participate in such a discussion when they are 'anonymous'. Recently, the
university tested a new webcasting system called Good
Mood, which successfully incorporates all of the above features. Read
the
evaluation for this project which was presented at the ALT-C 2006
conference in Edinburgh.
