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Tele Education Essay Research Paper 10 INTRODUCTION

Tele Education Essay, Research Paper 1.0 INTRODUCTION 1.1 Background of Tele-education Tele-education has a long history beginning with systems like that for teaching children in Australian

Tele Education Essay, Research Paper

1.0 INTRODUCTION 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: · a much wider

range of technologies are becoming more accessible to potential distance

education participants · the costs of technological delivery are dropping

dramatically · the technology is becoming easier to use for both tutors

and learners · the technology is becoming more powerful pedagogically

· 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. 1.5

Acronyms 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 POP Point-of-Presence 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: · Tele-education service · Content of

Tele-education · Network architecture · performance of

Tele-education · 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: · Tele-education NB · Delta ’s Virtual

College · 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;

· Voice · SMART 2000 computer teleconferencing · 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: · The network shall

experiment with different technologies and endeavor not to rely on any one

technology or any supplier. · Existing equipment and distance education

sites in the province shall be integrated into the network wherever possible.

· The network shall establish computer teleconferencing and computer

conferencing links among the sites, including access to electronic information

highway and the Internet. · Satellite delivery and reception capabilities

and upgrading of sites to PC-based videoconferencing will be investigated for

implementation in future. · Other optional equipment may be placed in

sites at the request of users and institutions such as MACs and CD-ROMs.

· 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: · classrooms where

on-line lectures and presentation take place, · group rooms where on-line

cooperative work takes place, · 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, · teacher

offices where it is furnished with course administration tools, · 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. 4.0

CONSIDERATIONS 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: ·

Tele-education service · Tele-education content · Network

architecture of Tele-education system · Performance of Tele-education

service · 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: a) Self-study · Individual work with web based course

material including exercises and discovery/reference search. · This

paradigm is supported by the hypermedia and WebStore services. b) Lecture

· Teacher to class presentation. · Supported by the conferencing

and hypermedia services. c) Group work · Discussions, exercises or

project work performed by the students in groups. This paradigm can also include

shared discovery/reference search. · It is supported by conferencing,

hypermedia, and WebStore services. d) Consultation · Student to tutor

consultation · 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 The course includes both

synchronous and asynchronous delivery methods. The duration of the course is

three to four days with approximately three hours of teaching and studying each

day. The course consists of five lectures, three self study modules and three

group exercises with a follow-up discussion of the results. The different

modules and modes of the course are conducted in a Tele-educational environment

which includes course outline information, a database of participants with

pictures and CVs, a WWW billboard supporting off-line discussions, access to a

WebStore and a tea-room which participants can visit for informal chats. The

lectures are performed by using video/audio conference tools. A system was used

to show slides on the participants web-browsers. The self study modules

contained web pages with information to read and small built-in exercises. The

group exercises consist of a number of questions to be answered by the group and

returned to the teacher for correction afterwards. When the teacher has

corrected the answers they are discussed in a conference with all the

participants. In the first trial a shared editor was introduced for use in group

exercises. The shared editor is a tool for synchronous collaboration on smaller

texts, and is meant to complement the chat and whiteboard tools used in earlier

trials. An illustration of the new shared editor can be found below. In the

second trial, a new floorcontrol-system for use during lectures as well as a

complete new graphical design of the virtual learning environment was tested.

The floorcontrol system was used by the teacher during lectures, to determine

which students wanted to ask a question, and to mute or unmute the microphones

and video cameras accordingly. A new graphical design of the User Interface (UI)

was introduced, in an attempt to create an even more homogenous UI. The

floorplan metaphore was kept, but new images and controls where implemented

throughout the environment. 4.1.2 An Introduction to Relational Databases and

SQL This course covered the theoretical principles of relational database

technology as well as supporting the hands-on skills of using relational

database language (SQL). Students took the course over a three day period, for

two hours each day. At the beginning of the course a one hour lecture outlined

the objectives of the course and provided an introduction to the topics. The

educational content comprised of text, graphics, and animation and was divided

into four sections, consisting of a total of twenty one modules (a module

typically being 1-5 pages). The course was made available via the Prospect

Tele-educational environment. On accessing the course, a separate courseware

browser window was opened, called the Virtual Student Desktop (VSD). All student

interactions with the courseware are facilitated via this VSD. The

Tele-educational environment is also accessible by the student for conferencing

and synchronous interaction. The VSD is rendered as a set of WWW windows,

frames, tool bar and icons. All native WWW browser buttons are suppressed

(hidden) so as not to distract the user from the main goal of education. A tool

bar specially designed for educational use is provided by the VSD at the bottom

of the screen. From this tool bar the student is able to contact tutors or

fellow students (asynchronously), access external systems, as well as navigate

and interact with the educational course material. Figure 3 illustrates a page

from a module in the course, and shows the educational toolbar at the bottom of

the screen and an index of the topics dealt with by this particular module in

the course on the left hand side of the screen. Figure 3 : page from module in

the course Overall the course comprised several different types of information:

Administrative (i.e. how to use the course etc.); A database of (self contained)

modules; Indexes or Roadmaps of specific courses through various modules;

Evaluation Forms and a Case Study. The roadmaps were important as the modules

can be combined in several ways to satisfy the different requirements for

different student objectives. Each roadmap corresponds to different learning

objectives of the RDBMS course. Thus the roadmaps provide a means of re-using

existing modules with as little redundancy as possible of educational material

and administrative overhead. A significant feature of the system was to provide

direct access to a real ?commercial? RDBMS via the same interface as the

educational course. The relational DBMS is seamlessly integrated into the

student educational desktop. Thus the tool bar offered by the VSD contains an

icon which allows students to issue SQL queries on a live database. The idea of

this is to deliberately blur the distinction between the educational environment

and the ?target? systems. This encourages students to ?try out? various

parts of the course before attempting a larger project. Another feature was the

ability of the student to store references to distinct locations in the course

material (bookmarks). Traditionally these are stored locally on the student?s

machine. However this has disadvantages as students rarely use the same machine

all the time. The VSD allows such bookmarks to be stored within the educational

service and are thus (privately) accessible to an individual student at any

time. Also if the student has logged off the course and logs back on, the VSD

allows him/her the ability to resume at his/her most recent position or restart

at the beginning. Various forms of on-line tutorials are embedded into the

course. ?True or False? and ?Multiple Choice Questions? are supported,

with automatic correction and notification of marks to the student. Form based

(short unstructured text style) answers are also facilitated in some tutorials.

In these cases the student answers are automatically delivered to course tutors

for subsequent correction. Also integrated into the course are evaluation forms

which, when completed, are automatically submitted and stored for later analysis

by course tutors. The VSD provides buttons to contact other class members or to

seek tutor assistance. Again, this is offered via WWW forms and integrated

transparently with an email delivery system. 4.2 Tele-education Content There

are several modes of educational interaction, which could be supported by a

virtual theatre/study room. These would include lecture presentation, course

material presentation and browsing, self-study, group work (shared

application/work, class discussions, group presentations), consultation

(tutor/participant, participant/participant), tutorial sessions, virtual coffee

room/virtual lounge, and continuous assessment. There are also some other form

of learning that have been identified. These forms of learning are: ·

Self learning · delivery of formatted courses material for students own

study · Lecture presentation · a one-to-many presentation by the

tutor of course or organizational material. · Exercises · the

facility to perform exercises either in groups or individually · Project

work · the development of sizeable projects using software outside the

teaching environment. · Discovery/Reference research · ability to

locate and access background or supplemental learning material ·

Seminar/Class discussion groups · many-to-many communication between

participants. · Consultation · private one-to-one communication

between participants. There is some overtap between these learning forms. For

example, exercises, project work, discovery/reference search can be part of the

self-learning form, but all of learning forms are listed here for completeness.

It has been pointed out that not only should the different modes of teaching be

supported in the Tele-educational environment but also the different styles of

learning adopted by the students need to be supported. So for instance students

who like to annotate their work or their course material should be facilitated

in doing so. This is very much in the spirit of hypertext origins of the WWW.

Another point raised is that multimedia activity in the virtual classroom should

be captured and associated with relevant course material. For instance, the

teachers comments on a particular slide could be captured with the slide in

question. Also the conversation of students working on group could also be

recorded and stored with the exercise. Course material could be presented as a

hyper-document with the participant capable of navigating through the document

or choosing the prescribed ordering of the presentation. In addition, the

participant could also be given access to the more traditional learning

material, for example, notes, books, etc. Course assignments could also be

electronically submitted to promote fast feedback on performance. An important

element of assignments and project work is the need to allow participants to

co-operate in groups. 4.3 Network Architecture of Tele-education System From the

application’s point of view, network operates as IP (Internet Protocol) network

routing both multicast and unicast IP packets. Connection from network level to

the Q-adapters managing the switches communicate via ISO stack over X.25 links,

but apart from this instances all network infrastructure is in support of IP

traffic. This network structure connects seven sites. The aim of the logical

network infrastructure is to provide stable network interconnections as well as

to be managed to some extent by the network management, and to provide a

working, broadband network infrastructure while also supporting an enterprise

model suitable for multi-domain environment. For the separate customer networks,

each sites posses of LANs of Ethernet, or mixed ATM/Ethernet LAN technologies.

For maximum efficiency of scarce international, broadband resources, only one

site in each countries (that taking part in Tele-education system) are

connected. The connection, internationally connected customer sites access the

public network ATM service via an ATM cross-connect (ATM XC) providing ATM

public network provider’s Point-of-Presence (POP) in each of relevant countries.

Each customer sites posses ATM Customer Premises Equipment (CPE) which is used

to interconnect ATM public network with local routers. For the connection within

the same country, it is performed via leased lines between routers at

internationally connected customer sites and sites not connected to ATM public

network provider. The ATM CPEs at internationally connected sites and routers at

all customer sites managed by VPN (Virtual Private Network) provider. It is

performed in concert with management of ATM public service by VPN provider to

provide Intranet style connectivity between hosts on customer site LANs. This

network is quite complicated because it connects seven sites in four countries

and consisting of the following core components: · Four ATM LANs ·

Seven Ethernet based LANs · Four ATM Cross Connects · Eight static

IP routes · Seven multicast routers · Two 2 Mbps leased lines

· Ten International ATM links (virtual path) · One basic rate ISDN

link The following is the figure of logical network infrastructure: Figure 4 :

Logical Network Infrastructure. The ATM infrastructure that represents ATM

public network provider consists of a single ATM XC at each internationally

connected sites. These XCs are interconnected by permanent VPs (Virtual Paths).

The ATM CPE at each site based on one or more Fore System ASX-200 switches. It

is employed as logically separate ATM LANs besides as providing ATM access

between public network and routers at each site. The following is the figure of

ATM configuration. Figure 5 : ATM Configuration. The IP configuration consists

of routers at each connected sites being connected by Permanent Virtual Channel

(PVC) running over VPs. The routing function at each site performed either by

dedicated hardware router or by workstations running routing daemon software.

Routing of multicast IP packets (used for multimedia conferencing applications)

is not fully supported by most current IP routers, therefore, routing performed

by multicast routing daemon (mrouteds) running on workstations. The mrouteds are

interconnected by unicast IP tunnels, which can be used to be routed via routers

together with all other unicast traffic. The IP tunnels between mrouted at

internationally connected sites used the second sets of VPs. This supports

partition of multicast traffic from other unicast traffic and thus enables

provision of more deterministic Quality of Service (QoS) for multimedia

conferencing application. For external infrastructure, the aim is to provide

international ATM links between IP routers at the customer sites. Parallel VPs

are used between each pair of sites; one for multicast routing and another one

for unicast routing. Figure 6 : The network configuration Reflecting the

contemporary trends in multimedia and information services, all software

communication is over IP, including management system traffic. For the network

infrastructures that are conducted at a single site, the requirement its network

is fairly simple, requiring simply Ethernet connection to support IP

communication between PCs and workstations. If the system includes the

management of connections over IP switches, then the network infrastructure

would include both a representative public network ATM cross connect and

customer premises network ATM work-group switch (a FORE systems ASX200). These

are connected and configured with multiple VPs to emulate a network with a

larger number of nodes. IP routing functions in this network are provided by the

SPARC workstations with ATM interface cards performing IP forwarding. The

following is the network configuration of this kind of network: Figure 7 :

Network configuration For this network configuration, the TES Customer is able

to request the set-up of a new connection to the TES provider. The TES provider

then requested the VPN provider to do likewise. The VPN provider made a request

to the Public Network Provider and Customer Premises Network Provider to ensure

that the end-to-end IP/ATM connection was in place for the TES Customer. This is

the goal for the configuration scenario. One of the most important on an ATM

network level management system is to provide end-to-end connectivity across

constituent ATM network element, and so support the connectivity provisioning

with fault management and quality of service features. Challenged by these

requirements, a system that is able to set up ATM Virtual Paths and to correlate

faulty conditions, determining how these fault effect the connectivity for each

end user has been built. The following is the Network infrastructure of this

system: Figure 8 : Network infrastructure The figure shows that all the network

equipment is connected to one Ethernet hub, that is, the hub that acts as a

backbone for one Public Network domain and two Customer Premises Networks. In

reality, this hub could be partitioned into a number of internets that are

inter-connected by routers, also known as the Internet. For the network that is

required to operate over six sites in four different countries, would require a

much more comprehensive network infrastructure. This infrastructure consisted of

an ATM VP service, leased lines, and the internal ATM and IP network

infrastructure. The following is the example of this network infrastructure :

Figure 9 : Network infrastructure 4.4 Performance of Tele-educational Service

4.4.1 Courses There were two courses, both aimed at students with above average

prior knowledge of computing and/or computer networks. The first, an

introduction to SQL, was a self-study course, consisting mainly of modules of

written text with assessments based on these. The second course, an introduction

to ATM, was led by a tutor and involved varied methods of delivery, including

lecture/seminar, individual study and group work. Students were therefore

expected to interact both with one another and with the tutor. This course, too,

included assessment modules. Both of the courses were offered over a three-day

period and students were expected to participate for three half days. Within

this time, those taking the SQL course was able to pace their own study. On the

ATM course, the students? use of the different resources was timetabled and

directed by the tutor. Time was divided between events, such as lectures, at

which all students were expected to be present, and study time, during which

they would work through a series of modules, with assessment associated with

each one. 4.4.2 Students There were 16 students on the more interactive of the

two courses, the Introduction to ATM, and a similar number on the self-paced

study course, An Introduction to SQL. All the students appeared to be

experienced computer users. This has to be accepted as necessary in a trial such

as this , which takes place in the context of a research project which uses

leading edge technology, some of it is still being tested. The prototypical

nature of parts of the system may make unusual demands on the students, such as

imposing unexpected delays. Having students who appreciate the difficulties may

well be important. Having said this, it appeared that although they were

knowledgeable about computers, these students were not experts in networked

multimedia technology, and did need some initial training in the use of the

software. This was given prior to the start of the course. The courses were

clearly directed at this target group, as their titles suggest. The students

also stated that they had a genuine wish to learn the subjects being offered and

that this was a major motivating factor. They were also paid for their

participation, which may have helped improve their persistence when there were

technical hitches. 4.4.3 System The system used for the ATM course is described

here. Those taking the SQL course used only those parts suited to self study.

There are three main elements: audio, and video communications channels support

a Tele-education system built on a web-browser base, but with considerable

functionality added. The audio tool, rat, allows participants to receive and

transmit audio, to identify who is speaking, control the volume of incoming and

outgoing audio streams. Since this tool was developed as a research platform,

there are many extra features which the average end-user is not likely to use in

an application such as this one, for example, the facility to change the audio

encoding scheme. The tool?s basic functionality is easy to learn and use. The

video tool, vic, also offers functionality suitable for its use as a platform

for research into networked video. For the non-expert, however, the most

important features are that multiple users can send and receive video

simultaneously and that they can control some features of both display and

capture/transmission (image size and frame rate are two examples). Video images

can be displayed at various sizes from thumbnail image to CIF. Enlarging images

does, however, involve creating a new window for each one. Students access the

Tele-education system via a web browser and navigate within it using hypertext

links, buttons and active areas of images. Initial access is password protected

and the system supports the notion of groups and hence, presumably of multiple

classes and tutorial groups. The interface is based on the metaphor of an

educational institution, a building divided into rooms whose function most

students will be able to predict from their real-life experience of education:

classroom, tea room, hall, office, library and seminar room. Users are presented

with an aerial view of the layout, in which the rooms are labeled. They gain

access to a room by clicking on the appropriate part of this image. The

resulting window sometimes maintains the metaphor but is more often mainly

textual – a list of hypertext links, for example. Once "in" a room,

students have access to the resources they need for the part of the course they

are taking. As might be assumed from the description, the system is intended to

support a mixed mode of course delivery, including lectures, group discussions

and assignments, individual study, assessment with feedback. The existence of

the office implies that students can also access relevant course administrative

information. The Hall and tea rooms suggest that the intention is also to

support less formal, social interactions. 4.4.4 Positive Findings The courses

both seemed to be appropriate for the target group. Students reported that they

believed they had learned a considerable amount and felt they would retain the

important points. The pacing of the study also seemed successful. The tutor

clearly had a sense that this was a real class in a real institution and made

considerable efforts to generate a relaxed and positive atmosphere. Use of

students? names, and greeting them as soon as they logged in, contributed to

this. This is no mean achievement, given the constraints. The tutor tended to

refer to the environment as if it were a real place, arranging with students,

for example, to "meet in the tea room" or telling them to "go to

the library". Whether the students shared this perception is less clear.

This may be due to the short time available to become familiar with it. It would

be interesting to see whether the environment would become more "real"

to the students over a longer course. The room-based structure therefore seems

to have been successful. The metaphor seems to have been well chosen, since

students seemed to have appropriate expectations of each "room". None

of them appeared to have difficulty navigating between different rooms.

Observation did show that some students had to scroll up and down repeatedly,

however, when they were working on individual study texts. This seemed

particularly to be the case where they found the material more difficult. Again,

there was no sign that they were unsure of where to go or had difficulty in

navigation. In terms of course delivery, the trial showed that students

experienced considerable variety in the ATM course (inevitably less so in the

SQL course). Not only this, but the tutor seemed able to exploit the flexibility

of the system and to direct the student to alternative areas of study from what

had been planned originally, if necessary. One of the problems with distance

education is that such flexibility can be harder to achieve than in a

face-to-face situation, so this is promising and an interesting result of having

different applications integrated in this way. It also has a pragmatic use:

given technical problems in one area, it was possible to shift students to

another activity quite easily. Interactivity, both structured and casual was

potentially considerable. The shared whiteboard used for group work was

perceived by students as a good feature. It seemed, however, that they did not

all realize at first that they could write and draw on it. Perhaps this should

be pointed out in the introductory sessions, or the whiteboard should be

accompanied by a short explanatory note. It would also be fair to say that this

was not a long enough trial to assess usability of this part of the system. In

the limited time it was also not easy for students to establish relationships.

The system and the way the tutor used it did encourage students to get to know

one another since, for example, one of the first activities for students was to

upload their CVs and pictures and to browse through those of other students. The

level of concentration appeared to be high. Naturally, as in a classroom, there

were moments when students? attention moved away from the subject of study but

these were not frequent. Interestingly, they usually stayed at the workstation

but moved to another activity such as reading e-mail. The students observed

"live" appeared to maintain concentration despite considerable

background noise and other potential distractions. This is not a surprise, since

other computer-based teaching and learning trials have drawn similar conclusions

- but it is another promising feature. At best, the material with which the

students were engaged appeared well designed for delivery on a computer screen.

The information was "packaged" into manageable chunks and was visually

stimulating. Diagrams, colour and animation were used effectively, and the

layout was clear and appealing. As the next section suggests, however, not all

of the written material was so suitable for this method of presentation.

Feedback was given to students both by the tutor, during discussions (for the

ATM course), and as a result of assessments done at the end of each module.

Students appeared to take these assessments seriously and were observed to

return to the relevant part of the notes when unsure or when they had given an

incorrect answer. The scope of this evaluation did not extend to assessing the

course design or the assessment methods, but it is worth mentioning that the

regular assessment seems to have been a successful feature of the course.

Awareness of other students is something that is hard to achieve in distance

education. Interestingly, with the audio channel left open during private study

periods, it appeared that students experienced something similar to working in a

library with other students around them. They were able to hear conversations

and could have asked questions if they needed to. The potential disadvantage is

that the additional background noise might interfere with concentration. It

would probably be worth investigating whether the availability or otherwise of

the audio channel makes a difference to students. 4.5 Operation and Management

of Tele-education Service A vital element of any service is the reliability,

configurability and administration of that service. In order to ensure success

of an educational service from both the participants? and tutor?s

perspectives, the delivered service must be well managed and monitored. It is

crucially important to realize the software and procedures necessary to manage

and deliver Tele-educational services over broadband networks. Four basic

principles for successful teaching in a virtual classroom environment have been

identified as · media richness, · interaction, · timely

responsiveness and · organization of materials. Media richness and

interaction mechanisms can be satisfied by the educational services described

earlier. The organization of course materials and the insurance of timely

response by systems, participants and tutors are goals of the management

service. During the delivery of a course, there is a significant mass of

material presented to participants as well as a high degree of interactive

responses amongst participants. Unless this mass of materials is organized and

interaction controlled, participants can become confused and disillusioned.

Proper maintenance and management of the dissemination of material must be put

in place to provide an effective learning environment. Segregation of material,

both between and within course modules should also be supported. The strategy of

?participant-paced? learning is important so as to ensure that the class

moves through the modules of a course together in order for the interactions to

be meaningful. Timely responsiveness has also been identified as a key

requirement for Tele-education. Thus access to course material, as well as other

participants and tutors, should be reliable and timely. To achieve successful

operation of the tele-educational service, participant (on-site) software should

be configurable for a wide range of computing environments. Also participation

of the class members should be manageable e.g. course registration, controlling

access to class discussions, automatic collection/distribution of assignments

and projects etc. The on-line management system should provide the range of

services as required by each course leader. 5.0 CONCLUSION Tele-education system

is a very new emerging technology. It has been applied in Europe and Canada, and

is still under study in order to improve it from time to time. From this

project, it is known that Tele-education is a revolution of distance learning in

which distance learning basically only provides asynchronous learning

environment. But Tele-education has improved it by providing both asynchronous

and synchronous learning environment. After studying all the materials found for

this material, it was found that Tele- education is not easy to implement. This

is because there are a lot of things need to be considered before implementing

such as what kind of network structures available, what kind of service can be

provided by network service provider, what is the most suitable network for

interconnection among the involved sites, etc. Another reason is that, after

implementing it, there need to have several trials on the service to look at its

efficiency which would take a long time. In general, it can be concluded that

Tele-education is becoming popular as the emerging of multimedia technology. Its

advantages that could overcome the problem in current learning environment also

has made it a preferable way of learning process. 6.0 REQUIRED EQUIPMENT AND

MATERIALS The following are the equipment or materials needed for the completion

of this project in third semester : a) Opnet software (Sun workstation) – used

to perform simulation b) TV Conferencing System with; i. ISDN Interface ii. H324

TV Conferencing Interface iii. Small TV camera iv. Speaker (stereo) ·

this is required for some experiment purposes on Tele-education system c)

Satellite System with; i. Antenna (2.6 m) ii. RF receiver (C-band) iii. 2 Mbps

TV conferencing Interface iv. ISDN (2B+D) Interface – Still under

study/discussion 7.0 SCHEDULE OF PLANNING (Timetable)

[1] Krebs, A.M, "D21A – The Initial Requirement Analysis", ACTS

Project AC052, http://www.fokus.gmd.de/research/cc/platun/coop/prospect/new/delivara.htm#D21A

[2] Jain, R, " A Revolution In Education", IEEE, 1997, pp. 1 [3]

Bison, T, "Distance Learning Is an Opportunity" , Circuit and Devices,

March 1997, pp. 41. [4] GammelGaard, A, "D21B – Final Requirement

Analysis", ACTS Project AC052, http://www.fokus.gmd.de/research/cc/platun/coop/prospect/new/delivara.htm#D21B

[5] Nielsen, A.B, "D53A – Evaluation of the First Trial Phase", ACTS

Project AC052, http://www.fokus.gmd.de/research/cc/platun/coop/prospect/new/delivara.htm#D53A

[6] Krebs, A.M, " D53B – Evaluation of The Second Trial", ACTS Project

AC052, http://www.fokus.gmd.de/research/cc/platun/coop/prospect/new/delivara.htm#D53B

[7]] Nielsen, A.B, "D51A -Operational Plan for First Trial", ACTS

Project AC052, http://www.fokus.gmd.de/research/cc/platun/coop/prospect/new/delivara.htm#D51A

[8] Johansen, A, "D51B – Operational Plan for Trial 2", ACTS Project

AC052, http://www.fokus.gmd.de/research/cc/platun/coop/prospect/new/delivara.htm#D51B

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