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Tele-Education Essay, Research Paper
1.1 Background of Tele-education
Tele-education has a long history beginning with systems like that for teaching children in Australian Outback, the British Open University and other such organizations. These built on the idea of correspondence courses where course materials are sent periodically by post and augmented the experience with broadcasts either on radio or on TV. The problem of student isolation was addressed partially through techniques such as telephone access or two-way radio links with teachers. At the end of 1980s, the vest majority of distance education throughout the worlds was still primarily print-based.
Technologies used for distance education are evolving from primarily ??one-way?? technologies and applications such as computer aided learning, computer based training and computer aided instruction, to more ??two-way?? technologies and applications such as computer mediated communications and computer conferencing systems for education. The significance of ??two-way?? technologies is that they allow foe interaction between participant and tutors, and perhaps even more significantly amongst participant themselves. This development has allowed and in some senses force researches to look more closely at the impact of educational environment, on the students learning experience.
In the future, it is expected that the telecommunications-based technologies to become the primary means of delivery of distance teaching. The reasons for this are as follows:
?h a much wider range of technologies are becoming more accessible to potential distance education participants
?h the costs of technological delivery are dropping dramatically
?h the technology is becoming easier to use for both tutors and learners
?h the technology is becoming more powerful pedagogically
?h education centers will find it increasingly difficult to resist the political and social pressures of the technological imperatives.
1.2 The Emergence of Tele-education
Radical changes in the computing infrastructure, spurred by multimedia computing and communication, will do more than extend the educational system, that is revolutionize it. Technological advances will make classrooms mush more accessible and effective. Today, classroom education dominates instruction from elementary school to graduate school. This method has remained popular for a very long time and will probably persist as the most common mode of education. However, classroom education has its problems, that is the effectiveness decline with increase in the number of students per class. Other pressures affect the instructors, many of whom are not experts in the material they must teach, are not good ??performers?? in class, or simply are not interested in teaching. The biggest limitation of the classroom instruction is that a class meets at a particular time in a particular place. This essentially requires all students and the instructors to collect in one spot for their specified period. But with the emerging technology, these problems can be overcome.
1.3 Reasons for studying Tele-education
The current Tele-education systems that have been applied in some countries are generally of multipoint transmission technique. It is found that, this kind of transmission technique having several problems or defects. Mostly, problems raised during the application of the system. One of the significant problems raised is that, for the multipoint transmission, the signals or information transmitted by the sender do not completely received by the receiver. This problem is might be due to error that occurs during the transmission of the signals or information. Another problem is lag of transmission. For this case, the signals or information transmitted do not arrive at all the receiver at the same time, for example, the question raised by the lecturer might not received by the students at the same time and this is not a good environment for Tele-education system. Some receiver receives the signals earlier than the others and some later or even not receives at all. Therefore, it is important to study the Tele-education technology from time to time to overcome these problems so that the Tele-education system could provide a more effective way of learning environment.
In order to have a lecture from, for example, a very famous professor from other country would require him to come at our place. But the amount of money spent for paying him to give lecture would be very expensive and this also would cause troublesome for him. However, this problem can be solved with Tele-education system in which the professor does not need to go anywhere else to give his lecture. This would save a lot of expenses and time.
Another reason is that, in normal classes the learning process would not be very effective if the number of students in a class is very big. This is because the lecturer alone can not coordinate such a large class. With Tele-education system, one lecturer could deliver his lecture to as many students as possible effectively in a way that a large number of students from different sites having the same lecture at once.
1.4 Purpose of Research
The purpose of this research is to study the current Tele-education system that has been applied in some countries. This study covers the background of Tele-education; that is its definition, the publications of Tele-education; that is any papers that discuss about Tele-education as a whole, the performance of applied Tele-education, and also the technology of Tele-education; that is its network architecture. But the main purpose of this study is to understand the Tele-education system that have been applied in another country and try to implement it in our country.
ATM Asynchronous Transfer Mode
CCITT Committee Consultatif International Telegraphique et Telephonique
CPE Customer Premises Equipment
IP Internet Protocol
ISDN Integrated Services Digital Network
ISO International Standard Organization
JAMES Joint ATM Experiment on European Services
LAN Local Area Network
MAC Medium Access Control
Mbone Multicast Backbone
PC Personal Computer
PVC Permanent Virtual Channel
QoS Quality of Service
RAT Robust Audio Tool
SLIP Serial Line Internet Protocol
TCP-IP Transmission Control Protocol – Internet Protocol
TES Tele-Educational Service
UI User Interface
VIC Video Conferencing Tool
VP Virtual Path
VPN Virtual Private Network
VSD Virtual Student Desktop
WAN Wide Area Network
WWW World Wide Web
XC Cross Connect
2.0 METHOD OF INVESTIGATION
Since Tele-education is a very new technology that is popularly discussed today, it is quite difficult for me to find any books that discuss about Tele-education from the library. Therefore, the easiest and the fastest way to gather information relating this project is via the Internet. I have surfed and found many interesting sites that discuss about Tele-education. Besides surfing, I also have contacted several people who are involved in this area, Tele-education, by e-mail . But unluckily, this does not really help because most of them did not reply. Besides using the Internet, I also get the information for this project from the IEEE Database at the library of Universiti Telekom.
3.0 BACKGROUND STUDY
3.1 Definition of Tele-education
What is Tele-education? Before discussing about what Tele-education means, lets look at what distance learning is. This is because Tele-education and distance learning are very related to each other. Distance learning is the acquisition of skills and knowledge through electronic communications that allow student and instructor to be separate in either in time or space. The to distance learning is ??asynchronous learning?? which can be defined loosely as learning at different time. It is a highly flexible method of training because the sender and receiver do not need to be synchronized in space or time. But Tele-education is more than that of distance learning. In Tele-education, not only asynchronous but synchronous learning is also made possible. In other words, Tele-education is the evolution of distance learning.
As stated before, asynchronous learning environment is not real-time environment. It is a self-study-based application and is accessed via the Internet to a server. The requirement to the student is only an ordinary PC with standard software and Internet access. This application is applicable for a large amount of users who can access the course independent of each other. The combination of the lecture-part, group-work-part, and self-study-part is another type of Tele-education learning environment, which is synchronous learning. It is a real-time environment. In this environment, students and lecturers can interact with each other simultaneously.
Tele-education use the technology of video teleconferencing that allows two or more parties at different geographical area to interact with each other or to have learning process together. But people usually get confused whether video teleconferencing can be considered as Tele-education as well. Tele-education is actually different with video teleconferencing in a way that Tele-education usually involve a large number of people as compared to video teleconferencing, that is, it is in video teleconferencing many people use a single monitor to see other people at other area but in Tele-education, students have their own monitor that can be used not only to see their lecturer and colleagues but also to send and receive educational materials.
3.2 Publications of Tele-education
There are many papers discussing about Tele-education. Most of these papers cover only the general or overall scope of Tele-education. The area of discussion on Tele-education can be summarized as the following:
?h Tele-education service
?h Content of Tele-education
?h Network architecture
?h performance of Tele-education
?h operation and management of Tele-education
For Tele-education service, it describes about what multimedia tele-service and hyper media service is, and how it can be integrated into Tele-education service. It also describes about what Tele-education service facilitate. Content of Tele-education describes about the style or mode of Tele-education system, that is, what kind of education style used, and how the lecture notes or any materials delivered to all the students. For network architecture, it describes about the protocol used for the Tele-education system and its network infrastructure. Performance of Tele-education covers the performance of service of Tele-education and also the network performance. The description of these performances is from the customer point of view. For the operation and management of Tele-education, it describes about what should be taken into consideration in order to provide a well managed Tele-education service.
3.3 Examples of Systems
From the study of materials gathered, there are generally three examples of Tele-education system that have been applied in the Europe and Canada. Those examples are:
?h Tele-education NB
?h Delta ’s Virtual College
?h ACTS Project AC052 (RACE Project Report)
The purpose of looking into these examples is to try to understand what kind of Tele-education system is implemented, how Tele-education can be implemented, to know what are the requirements to implement it, and what considerations should be taken into consideration for implementing it.
3.3.1 Tele-education NB
Tele-education NB is implemented at the University of New Brunswick, Canada. The present physical network consists of three independent networks that operate on telephone lines;
?h SMART 2000 computer teleconferencing
?h Computer Mediated Communications using NBNet
The SMART 2000 bridge for computer software sharing and audiographic teleconferencing is owned and operated by the Tele-education NB. This is accessed by simple dial connections using ordinary telephone lines. This allows for the computer monitor at each site to show images created by users at the other sites. The software can be used like an elaborate electronic blackboard, overhead projector, or slide projector. In addition, it is being used for software sharing at multiple locations.
Data communications are transmitted over NBNet using a SLIP server which resides in a user friendly simple menu front-end created by Tel-education NB to permit easy access to NBNet and to facilities available. Students and teachers can access NBNet for uploading and downloading assignments and other course materials. A CD-ROM server is being set up at the central site and at the University of New Brunswick library for permitting access to different databases.
Tele-education NB also supports an on-line learning center with a file server located at Mount Allison University. Information of relevance distance education and the network in particular can be accessed there. In Tele-education NB, a special listserv is created for internal communications among different sites. As an integral part of the province’s electronic information highway, Tele-education NB is supporting the development of an open, distributed network, taking advantage of media available. The most widely used delivery modes are audio teleconferencing with SMART 2000, as well as videoconferencing. However, it is not limiting the network to any one technology, or suite of technologies. It is actively promoting experimentation and cooperation in the reception and delivery of courses using other software and media.
Tele-education NB placed routers in the Community College Campus in each region, and other sites in regions that do not have a college. Initially it operates using 56K connections and will move T1. SMART 2000 runs not only on regular telephone lines but also on LANs and WANs using Novell, TCP-IP and other telecommunication protocols. Tele-education NB are now experimenting with synchronous transmissions using the TCP-IP protocol on NBNet. The Picturetel videoconferencing units existing in province all are CCITT compatible.
Tele-education NB has provided the guidelines for selecting appropriate technology for its network as follows:
?h The network shall experiment with different technologies and endeavor not to rely on any one technology or any supplier.
?h Existing equipment and distance education sites in the province shall be integrated into the network wherever possible.
?h The network shall establish computer teleconferencing and computer conferencing links among the sites, including access to electronic information highway and the Internet.
?h Satellite delivery and reception capabilities and upgrading of sites to PC-based videoconferencing will be investigated for implementation in future.
?h Other optional equipment may be placed in sites at the request of users and institutions such as MACs and CD-ROMs.
?h The network should be compatible as much as possible with other provinces and regions.
3.3.2 DELTA’s Virtual College
Delta’s Virtual College is implemented in Denmark (Europe). It offers the opportunity for students to participate in desktop Tele-education from their homes or offices. This concept means that individual students participate in Tele-educational courses using a desktop computer online connected to a course provider.
The user interface is a common Web browser, that is, Netscape Web-browser, extended with loosely integrated audio and video tools. The educational environment applies the metaphor of a virtual college. The idea is that students access DELTA’s virtual college server when participating in a course. The user interface looks like the plan of a college. From the college hallway, the student can enter different rooms with different functions. Those rooms are:
?h classrooms where on-line lectures and presentation take place,
?h group rooms where on-line cooperative work takes place,
?h studies where off-line study such as self-study material, exercises, slides from previous lectures, supplementary material and links to other sites on the Web take place,
?h teacher offices where it is furnished with course administration tools,
?h tea room where it is used for informal chat and social contact with fellow students during break.
The following figure, the “floor plan”, illustrates those rooms:
Figure 1 : The floor plan
The goal of this virtual college is to integrate different modes of teaching and learning. This includes synchronous mode like on-line lectures and group exercises as well as asynchronous mode like interactive self study, participation and threaded bill board conferences and sharing of documents.
The virtual college is run primarily in a local network environment in order easily to monitor and control the students and technology. Then, when there are several countries participate, each sites are connected by the JAMES (Joint ATM Experiment on European Services) broadband network.
3.3.3 ACTS Project AC052 (RACE Project Report)
This is a big project on Tele-education. It covers the whole aspects that should be taken into consideration for implementing Tele-education in Europe such as service aspects, management aspects, network architecture, etc. In this project, there are several trials have been done in order to obtain an effective Tele-education system. The details of this will be discussed later throughout this report.
It is not easy to find materials or any papers reporting the architecture of Tele-education. Most of the materials found are basically discussing about the general idea on what Tele-education system is, for example some papers discuss about the general system of a Tele-education service offered, its advantages over current educational environment, etc. However, I managed to find a very interesting material discussing about Tele-education as a whole, that is the ACTS Project AC052 (RACE Report Project). Therefore, I choose this report as my main reference in doing my study on Tele-education overall system description covering the architecture.
There are basically five main topics that are going to be discussed in quite detail regarding the Tele-education as a whole in this report. These main topics are:
?h Tele-education service
?h Tele-education content
?h Network architecture of Tele-education system
?h Performance of Tele-education service
?h Operation and management of Tele-education service
4.1 Tele-education Service
The multimedia tele-service provides both core and management services. The multimedia tele-services are briefly described as Video/audio conferencing service, which based on the MBONE (Multicast Backbone) tools VIC (video conferencing) and RAT (audio conferencing). Hypermedia service allows access to be provided to hypermedia information stored on a WWW server. The WebStore service is a managed WWW based multimedia document store, which allows users to store and retrieve arbitrary documents (text, video, audio, etc.), using the well-known interface of the WWW. The management of the WebStore includes subscription, accounting and access control.
A mapping between the learning forms and the multimedia teleservices has resulted in a list of four basic paradigms:
?h Individual work with web based course material including exercises and discovery/reference search.
?h This paradigm is supported by the hypermedia and WebStore services.
?h Teacher to class presentation.
?h Supported by the conferencing and hypermedia services.
c) Group work
?h Discussions, exercises or project work performed by the students in groups. This paradigm can also include shared discovery/reference search.
?h It is supported by conferencing, hypermedia, and WebStore services.
?h Student to tutor consultation
?h Supported by video/audio conferencing and hypermedia services.
In order to support these four paradigms the multimedia services are integrated into a Tele-educational Services (TES) which provides both the core service and the management service functionality. The core Tele-educational service provides two user interfaces, one for the teacher and one for the students.
In Tele-educational service, each course, presented as part of Tele-educational service, would involve the rendering and seamless integration of audio, text, graphics/bitmaps and appropriate video segments, to suit the presentation of the course material. An educational service would also facilitate the interaction of course participants with one another in class discussions, as well as with the course tutor. In this way, a course tutor can guide debates on issues arising from course material and allow participants to exchange views and share experience. This interaction is very important, as participants need to be encouraged to learn both from the tutored course as well as from each other’s practical experience. This forum of discussion also supports the tutor in assessing feedback from the participants concerning the comprehension, benefit and effectiveness of a course for participants.
The educational service could also facilitate access to simulation environments and ‘live systems’, which are parts of the participant’s course material. For example, it could provide access to specific commercial database information, which would be part of a Database Modeling course. In this way, access may be gained to systems and information, which would otherwise not be available on the participant’s site. Course could be taken when the participant’s work schedules permitted. Similarly, participant/participant interaction could be scheduled flexibly. An educational service can be seen as incorporating several interaction (tele-services) and course presentation mechanism, for example, multimedia presentation tools conferencing, e-mail or notice board systems.
The following is an example of service layer used in the ACTS Project AC052:
Figure 2 : Service Layer
In the ACTS Project AC052, there are two Tele-educational courses offered as a trial of the management service. These courses are ” An Introduction to ATM ” and ” An Introduction to Relational Databases and SQL “.
4.1.1 An Introduction to ATM