Web based multimedia support in computer networks course: a case study




НазваниеWeb based multimedia support in computer networks course: a case study
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WEB BASED MULTIMEDIA SUPPORT IN COMPUTER NETWORKS COURSE: A CASE STUDY


Bülent Gürsel Emiroğlu

Baskent University, Department of Computer Engineering, Ankara, TURKEY

emiroglu@baskent.edu.tr


ABSTRACT


The purpose of this study is to show the difference between the classical, instruction based in-class education and web supported tutorial based in-lab self study education for the “Computer Networks” course in the Department of Computer Engineering. This paper aims to show the effect of using web based multimedia (animations, simulations and applets) in the subject “computer networks” for visualizing the activities virtually rather than experiencing in real conditions. The further goal of this study is to differentiate between traditional lecturing by the active role of instructor on the board and constructivism based tutorial guided self-study learning in the computer lab whereas the instructor acts as a facilitator, for the teaching of “computer networks” subjects at the university.


Keywords: Web Supported Learning, Multimedia Support for Teaching, Computer Networks


INTRODUCTION


Education is a field affected by the developments in the technology leading to reach better standards in the teaching and learning environments. That’s why the methods and techniques that have been formed over the long years may change relatively. In the past years, the field of higher education has been impacted very much from the developments on the Internet and Web technologies. There are always divided opinions for what is the best learning environment online, whether it was web based or web supported. It is likely an enthusiast will appreciate highly a web based learning environment and believe this will replace classrooms in the future. On the other hand, a traditionalist might be more careful to adopt a learning environment fully online, and it is likely that web supported option is more welcome here. However, the distinction between these two options is not always clearly made for learners, or even for instructors. Web based learning environment can be defined as at the least 50% of teaching and learning activities, for instance, discussions, questions, comments, and feedback evaluations are conducted through the web or web courseware. On the other hand, web supported learning environment can be defined as less than 50% of mentioned activities are forwarded by the web or web courseware. Over a half part of mentioned teaching activities are dominated by traditionally face-to-face classroom teaching.


Considering the enormous amount of activities in the field of educational technologies, a variety of approaches, architectures, and systems have emerged in the last decades. Current development models for the utilization of new technologies in the educational sector are insufficient, because they either focus on technology (software development models) or on didactics (didactical models). Due to the improvement in Information and Communication Technologies (ICT), web based multimedia support materials such as Java Applets and Flash Animations allow teachers and instructors of engineering departments to provide a better environment for learners to visualize concepts and apply their theoretical knowledge on the real applications, especially on higher education in universities.


After the technology became available and easily accessible for the instructional use in higher education, the learning is enhanced with the help and support of related technology used and applied by the teaching staff. Technology enhanced learning can be defined as the way of learning with the support of appropriate technology and guidance of the teacher in a specific subject manner applied in the educational domain. Its not like distance education or web based training, but can be defined as if it is “blended learning” whereas it combines traditional in-class education conducted with the teacher and the technological support provided with the available resources. Schmees (2006) states that in case of technology enhanced learning, ICT are used to support activities in teaching and education. In addition to e-learning, where learning technologies help achieving desired learning results, TEL also comprises activities without influence on this result, e.g. course or content management. Learning management systems (LMS) are the most frequently used applications in TEL. They are also known as learning platforms or portals and provide uniform access to provided resources. Much of the literature on technology enhanced learning shows that one of the main barriers to the effective use of teaching materials is the technology (for example, poor access, slow downloading) rather than the design of the learning materials themselves. It is vital that teachers take on expert help with technical issues in the planning, design, and delivery of web based learning programs.


The quality of a learning environment depends on a variety of aspects. The combination of didactical, technological, and domain expertise is crucial for designing successful learning environments. (Adelsberger, 2000) The traditional course model, in which the lecturer follows a text book, prepares and exhibits slides, and presents some theoretical exercises, is not enough to assure a precise comprehension of what is being taught. The problem is due to both the teaching model and the lack of appropriate tools capable of translating the theory being presented into a more practical reality. And without a practical vision the student tends to lose touch and just “float” around the introduced concepts and mechanisms without gaining a realistic view of what is really going on. (Maia, Machado, Pacheco, 2005) However, Oliver and Hannafin (2001) states that, in constructivist learning environments, the goal of encountering and addressing student’s naive theories and models forms the basis for designing and implementing lessons and activities. Naive mental models are coherent for the learners who hold them, thus experiences that serve to illustrate their limitations are critical to promote heightened awareness and revision (Hannafin, Hannafin, Land, & Oliver, 1997). Similarly, ChanLin (2008) argues that the assumption underlying constructive learning is students’ active participation in the learning task given. A common constructivist goal is to support intrinsic motivation and self directed learning in a meaningful context. To promote such learning, one approach is to equip students with hypermedia tools to explore knowledge and design knowledge artifacts within a learning community (Chen and McGrath 2003; Erickson and Lehrer 2000). Teachers need to take part in planning the environment for technology integration and promote inquiry. Moreover, ChanLin (2008) states that when integrating technology into learning, students are more likely to build on what they learn from technological skills and experiences when their existing knowledge is acknowledged and made central to the learning process. From this perspective, linking technology-focused knowledge construction to students’ needs and interest rather than simply delivering technical training isolated from the curricular or instructional objectives need to be emphasized. Similarly, Page, Buss, Fishwick, Healy, Nance and Paul (1999) points out thatexploration”, “discovery-based” and “learning by doing” are valuable methods of learning which give a learner the feeling of involvement. The availability and interactive nature of web based simulation provides a good medium for students to experience the complexity and dynamism of collaborative work and can be natural environments that combine distance education, group training and real-time interaction. (Page, Buss, Fishwick, Healy, Nance and Paul, 1999) In an active learning environment, on the other hand, students are given some general directions and then left to actively pursue the knowledge for themselves with the possible help of the instructor when needed. Use of appropriate software tools can help encourage and support active learning. Software-based learning environments generally provide users with a workspace, tools, and instructions for engaging in problem solving tasks. These tasks tend to be interactive in nature, with the user given some freedom for exploration and experimentation beyond just the scope of the assigned task.


On the other hand, Fischer, Troendle, Mandl (2003) argues that university education has largely remained unaffected by developments in web-based learning technologies. Too often, multimedia applications in university lectures are restricted to Microsoft Power Point slides and the Internet is used merely for e-mails or to present some Web pages containing staff information and lecture content. Thus far, university students have not profited extensively from ICT use to facilitate learning processes. Online seminars are often constructed within the constraints of specific group ware, rarely using design principles derived from theoretical approaches to learning. Tele-teaching applications, for example broadcasting lectures through one-to-many videoconferencing often simply attempt to emulate traditional practice with new media.


As we already know, the goal of every computer science department is to maintain a top-notch educational program in order to prepare its graduates for successful careers in the computing field. Most programs now couple traditional educational methods with more modern techniques such as active and team-based learning environments, online course materials and computer-based laboratories. Most educators see this coalescence of traditional and modern learning techniques as critical to providing well-rounded educational experiences for its students. (Hill, O’Neal, 2005) Computational science is an emerging graduate and undergraduate discipline, whose primary focus is the application of computational techniques to understanding, applying, and advancing the sciences. The computational techniques cover many areas, including high-performance computing and distributed collaborative work, but most involve modeling and simulation at their base. (Cunningham, Shiflet, 2003) Through web programming and the use of Internet technologies, designers can produce interactive course materials containing online activities, animations and simulations to support in-lab activities for the students. Similarly, Bogaard, Vullo, Cascioli (2004) declare that helping students to understand complex ideas will always be problematic for teaching professionals. Often, the students can be limited by not only their imagination, but by their experiences. When trying to explain something that is outside of the students’ imagination, it is often helpful to have either simple animations or even interactive simulations that the students can explore. The creation of interactive environments and the use of animation can greatly help educators get their point across and, as a result, help students comprehend the ideas.


Computer technology can be used to make very exciting and fun animations (Java Applets and Flash Animations) into which education and training can easily be incorporated. For example, science subjects can be thought by using computer animation. Instructors can also use computer animation to demonstrate things visually exactly how they want to since they have control of every aspect of the animation. It can be used to show how things come together and work together. In science for example, animation might be used to show how computer networks work. Instructors can create realistic models of those things like computer networks from the data they have and look at the way these parts of the systems will interact with each other. They can get a real animation of their experiments and look at it from different angles. Therefore, they can make an animation experiment exactly like the realistic in the lab with regard to materials and results. Therefore, computer animation also allows instructors to do things that would be extremely hard to do in real life. For example, exchange and overflow of the data within a computer network can be showed with well designed Java Applets and Flash Animations. Well-designed animations that are relevant to the topic can facilitate learning if helping the learner to form mental representations that integrate the dual visual and auditory channels, through which learners receive and process information. Animations are best suited for representing events that are procedural in nature, complex, or difficult to observe in the real world due to speed of occurrence, size and scope, etc.




The ability to carry out interactive learning sessions and simulation capabilities over the Internet is important. So far, most successful course development work over the WWW facility is in a passive learning format. Interactive experience can lead to improved learning. Palakal, Myers and Boyd (1998) states that hypothetical simulations with graphical output and interaction make a learning experience more realistic and interesting to demonstrate concepts in courses such as computer architecture, theory of computation, data structures and algorithms. (Palakal, Myers, Boyd, 1998) As stated before, the World Wide Web has become the most prevalent and pervasive information system. Today’s educators are utilizing this, from minimally putting course material on the web to holding entire courses online. Unfortunately, this is the limit to how many professional educators use this resource. Many are missing the opportunity of not only putting information online, but also interactive environments or simulations for their students to explore to help them better understand complex ideas. (Bogaard, Vullo, Cascioli, 2004) Many studies have examined the effectiveness of the Web as a study tool in terms of the various options it offers: asynchronous discussion forums, synchronous discussions (text, voice and/or video) and animated illustrations and multimedia applications in general. (Gal-Ezer, Lupo, 2001) However, it seems that students feel that the virtual learning environment cannot replace the live classroom, with its personal interaction between the students and the tutor and among the students themselves. The Web serves as an additional self-learning tool for the students when they sit alone at home and need to cope with the material from a distance, which requires a high level of self-learning ability on their part. Students who are used to the face-to-face study format from their previous experience, and especially the introductory students, find it difficult to use the Web as a study tool. In contrast, advanced students, who have developed self-study skills, were able to use the Web more efficiently. Where education is concerned, revolutions are unacceptable. Hence, the process of integrating technology into education must be evolutionary. Educators and policy-makers, separately and together, must carefully examine where the technology can help, and where it has little value.


Ursyn and Sung (2007) declare that in student-centered learning environment, students are actively involved in studying science by visualizing selected topics and producing graphical illustrations versus written descriptions of concepts they learned. Student cognitive skills enable them to interpret and comprehend the concepts they are studying by the way they make non-verbal representations of ideas and create or receive visual messages about science concepts. By creating knowledge based sketches and graphics, students learn about current approaches to dynamic presentation of data. There is growing demand in many disciplines for visual aids, scanned images, graphics, and dynamic images that display information or promotional materials. Multimedia materials, (images, simulations, sound, video, etc.), designed for lectures, books, references, computers, and web space are widely available and proven to be effective in science, both in teaching and learning. However, these materials are mostly produced by professionals who understand the concepts. Involving learners in the production process of visual illustration of basic science concepts has not been experimented with or reported in physical science courses.


While computers afford the design of highly interactive open-ended learning environments, decisions about how to design the instruction used in conjunction with the technology are often made with little understanding of how the user will perceive, process and interpret the resulting feedback that it provides. Tailoring the Java Applets and/or Flash Animations to the needs and goals of a particular course requires an understanding of the capabilities of the simulation and the ways it introduces and enforces various networking concepts. (Cameron, Wijekumar, 2003)


The importance of the Internet and the Web makes it clear that the basic principles of computer networks should be understood by every student majoring in computer science. In fact, making these principles accessible to an even broader audience is a worthwhile goal. Java applets serve two roles: one as a visual representation of different scenarios for the concept in question; the second as a vehicle for experimentation. The applets are designed to encourage user interaction. The user can make changes in parameter settings and then restart the applet to see the effect of the changes. (Holliday, 2004)


Recently, many interactive environments have been introduced on the web to support the learning of computer networks. These environments try to help users to understand better the complex interactions between processes within the execution of a computer networks. It is believed that studying the algorithmic aspect of communication protocols is the proper way to give the students insight into the problems and the tradeoffs involved in the design of computer networks. Communication protocols are complex algorithms which have characteristics that are unfamiliar to high school students: they are distributed, concurrent and they include uncertainly since it is never certain when, and if at all, a message sent from one end of a communication link will reach the other end. (Shifroni, Ginat, 1997) Teachers that tried to teach the protocols in a frontal lecture-type explanation reported that the majority of the students had severe difficulties in understanding the distributed and concurrent occurrences. In particular, the students found it hard to understand handling of message loss, message reordering and message duplication in computer networks. Often users can investigate interesting behavior and properties of algorithms by modifying respective parameters of the distributed computer systems. Although many of these environments have been created under educational aspects and provide a wealth of tools to help students, little is known about how teachers and students actually use them in class. An analysis of these results, from the perspective of seeing what such Java Applets and Flash Animation tools need to provide in order to be successfully used in class and how users (teachers, students) can be helped to improve the performance of the learning process. (Koldehofe, Papatriantafilou, Tsigas, 2003)


METHOD


Subjects


This study is conducted at the Baskent University, Engineering Faculty, Department of Computer Engineering during the autumn term of the 2007-2008 academic year. The participants were the students of the “BIL 431 Computer Networks” course; whish is a compulsory course within the curriculum of the computer engineering in the university. Totally 54 students, 46 students from the 4th year and remaining 7 from the 3rd year, all from the Computer Engineering BSc (Bachelor of Science) program under Faculty of Engineering, Baskent University, Ankara, Turkey.


Instruments


Three achievement tests were used to assess the students’ achievement on “Computer Networks” subjects during the 10 weeks period.  All achievement tests were developed by the researcher, including both open-ended and multiple choice questions on the curriculum of the “Computer Networks” course. The subjects were: The Physical Layer, The Data Link Layer, The Medium Access Control Sublayer, The Network Layer, The Transport Layer, The Session Layer, The Presentation Layer, The Application Layer, Network Security, Internet and the Web. At the related weeks (on the 3rd, 7th and the 10th week) of the assessment tests, after the tests were developed by the researcher, three experts (two subject area specialist and one instructional technologist) assessed the test in terms of validity and relevance to the subject matter. According to the feedback collected from the experts, the tests were revised.


Procedure


Experimental and control group design was used. The study included 54 students (3rd and 4th year) enrolled in the “BIL 431 Computer Networks” course in the Department of Computer Engineering, Baskent University, Turkey. All the students are attended the theoretical part of the course, 5 hours per week, during the first 4 weeks. After 4 weeks, equally-sized groups are organized according to the surnames of the students on the class list. The first group, 27 students, composed of 22 students from the 4th year and remaining 5 students from the 3rd year; the second group, 27 students, composed of 24 students from the 4th year and remaining 3 students from the 3rd year, all members of the Department of Computer Engineering. During the remaining 10 weeks of the academic term, for the two-hours session of the course, while the control group was exposed to traditional education by the instructor in class with direct instruction on the board and presentation by the computer and the data show, the experimental group was in the computer lab, following the instructions written on the printed tutorial guide for accessing and interacting with the Java Applets and Flash Animations on the web to practice and visualize the concepts in the “Computer Networks” course. Table 1 below shows the data collection and analysis procedure for the two groups.


During that 10 weeks period, for measuring the performance of the students on the subjects covered, 3 assessments are implemented on both groups, at the same time. At the end of the term, the results are compared, showing that the use of multimedia (animations and simulations on the web) created a positive effect on the success rate of the experimental group, as seen in Table 2.



Table 1: Data collection and analysis procedures

Groups

Treatment

Assessment

Data Analysis

Control

(28 students)

Traditional classroom instruction

(10 weeks)

Achievement test

Means of the

students’ grades at the assessments

Experimental

(28 students)

Web based animations and simulations as learning support tools (10 weeks)

Achievement test


Table 2: Mean score results of experimental and control groups

Groups

Scale

Means of the 1st Assessment

Means of the 2nd Assessment

Means of the 3rd Assessment

Means of the all assessments

Control

(28 students)

100

57.3

62.5

55.2

58.3

Experimental

(28 students)

100

60.8

68.7

72.1

67.2




FINDINGS


The adoption of a constructivist pedagogic model opens excellent perspectives for improvements in computer networks course both in teaching and learning. A big pedagogic advantage of using “computer networks” Java Applets and Flash Animations is the construction of a hybrid teaching-learning environment where conventional expositive lectures and simulations may be combined. The use of the Java Applets and Flash Animations might also contribute to reducing the total time needed for theory presentation and explanation, perhaps extending the practical sessions, and possibly creating new laboratories. This way, the cooperative approach is applied in classroom and the constructivist thinking can be introduced to support knowledge construction, making it possible to experiment with the newly introduced theories. In this study, the results showed that the use of multimedia (web based Java Applets and Flash Animations) created a positive effect on the success rate of the experimental group by means of level of student achievement than traditional instruction conducted with the active teaching by the instructor. 


RESULTS AND DISCUSSION


The Computer networking has long been regarded as one of the more difficult technology-related subjects to teach. Historically, this type of course was thought to require much hands-on interaction with the instructor. Due to recent advances in network simulation technologies, complex networking systems are easily modeled on the computers with the Java Applets and Flash Animations. (Cameron, Wijekumar, 2003) Moreover, the use of interactive learning tools, such as animations, simulations and applets, have the potential to increase the student motivation in learning environments. Simulations offer immediate feedback and allow the learner to explore different alternatives when needed. Simulations enable knowledge application through multidimensional problem solving and improve knowledge transfer leading to discovery-based learning.


A simulator attempts to create a dynamic and simplified model of reality. In educational applications, we consider its potential far more efficient than other conventional tools. Within the sphere of computer science there are simulators supporting the teaching of various disciplines such as operating systems, computer networks, programming and computer architecture. Additionally, interactive computer graphics (Java Applets and Flash Animations) are powerful tools that can be used in the educational process. The research shows that learning process is highly enhanced when this kind of approach is used in computer science teaching, not only because of the motivation they engender, but also because high end results can be easily generated with relatively little effort. In fact, interactive tools are growing in importance for supporting computer science learning, since they are capable of covering many of the typical topics included in the curriculum: Linear Algebra, Artificial Intelligence, Computer Graphics, Network, Real Time Simulations, Human Computer Interaction, Software Engineering, among other important topics.


Moreover, web based instructional multimedia is getting popularity and playing an important role in the academic enterprise of teaching and learning at the field of higher education in universities. On this study, assessment results showed that, if provided by the well designed guidance of the instructor, multimedia content (Java Applets and Flash Animations on the web) can help to facilitate learning in the “Computer Networks” subjects. Furthermore, although applied within a small sample, this study shows that using web based technologies as support tools in computer science subjects may increase the success rates of the students if applied within a constructivist approach well-designed by the instructor of the related subject domain.


REFERENCES


Adelsberger, H.H., Bick, M. Pawlowski, J.M. “Design Principles For Teaching Simulation With Explorative Learning Environments”, 2000, Proceedings of the 2000 Winter Simulation Conference, pp 1684 – 1691


Bogaard, D.S., Vullo, R.P. Cascioli, C.D. “SVG for Educational Simulations”, SIGITE04, October 28–30, 2004, Salt Lake City, Utah, USA.


Cameron, B. H., Wijekumar, K., “The effectiveness of simulation in a hybrid and on-line networking course”, 2003, In Proceedings of the 34th Technical Symposium on Computer Science Education, pp. 117-119. Reno, Nevada


ChanLin, L.J. “Technology integration applied to project-based learning in science”, 2008, Innovations in Education and Teaching International Vol. 45, No. 1, February 2008, pp 55–65


Chen, P., McGrath, D. “Moments of joy: Student engagement and conceptual learning in the design of hypermedia documents”, 2003, Journal of Research on Technology in Education, 35(3), 402-422.


Cunningham, S., Shiflet, A.B. “Computer Graphics in Undergraduate Computational Science Education”, SIGCSE’03, February 19-23, 2003, Reno, Nevada, USA.


Erickson, J., Lehrer, R. “What’s in a link? Student conceptions of the rhetoric association in hypermedia composition”, 2000, Computers as cognitive tools: Vol II: No more walls, pp. 197-226. Mahweh, NJ: Erlbaum.


Fischer, F., Troendle, P., Mandl, H. (2003) “Using the Internet to Improve University Education: Problem-Oriented Web-Based Learning with MUNICS”, Interactive Learning Environments, 11:3, pp 193 – 214


Frigg, R., Hartmann, S., “Models in Science”, The Stanford Encyclopedia of Philosophy, 2006, Zalta, E.N., (Editor). http://plato.stanford.edu/entries/models-science/


Gal-Ezer, J. Lupo, D. “Integrating internet tools into traditional CS distance education: students’ attitudes”, 2002, Computers & Education 38 (2002) pp 319–329


Hannafin, M.J., Hannafin, K.M., Land, S., Oliver, K. “Grounded practice in the design of learning systems”, 1997, Educational Technology Research and Development, 45(3), 101-117.


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