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Multimedia Software Engineering, Computer Aided Instruction, Object-Oriented
Design, Network Protocol Analyzers
Disclaimer: The views
expressed herein are those of the authors and do not purport to
reflect the position of the United States Military Academy, the
Department of the Army, or the Department of Defense.
Abstract: Educators are
showing an interest in media rich presentation systems as a means
of giving additional material to a class or of showing concepts
in a graphical fashion during class. Educators have concerns,
however, about the length of time it takes to design and implement
media rich or multimedia systems, about copyright issues, and
whether the system will be used more than once. They also want
to be able to design the system using sound instructional principles,
but may not have any time for acquiring such specialized knowledge
and, indeed, they probably did not take any education classes
while working on their advanced degrees. They do not want to
spend a great deal of time in learning how to use a multimedia
package nor do their students who may only need to do a multimedia
system once to fulfill the requirements of a project or degree.
Although educators and students could use expensive
instructional design and multimedia packages, they can accomplish
the same objectives with the World Wide Web (WWW) using the Hypertext
Markup Language (HTML) and SIMPLE designed by Marion Hagler and
Bill Marcy at Texas Tech University. Both are easy to learn to
use in a short period of time and are free to educators and students.
Currently, however, neither HTML or SIMPLE incorporate instructional
design, hypertext design, or interface design nor were they implemented
to do so. HTML provides a mechanism for allowing media rich presentations
to be made on the WWW and SIMPLE lets instructors pull already
designed and implemented instructional materials together into
In order to help educators and students to design
effective and instructionally sound systems quickly, a hypertext
instructional design engineering process can be used to help them
to concentrate on structuring their system and on monitoring design
violations. The process includes a requirements stage, a specifications
stage, an implementation stage, validation for each stage, and
evaluation of the resulting system. The products of these stages
are developed with object-oriented techniques which will eventually
result in a hypertext system for instructional usage. The process
has been utilized to develop a system for teaching machinists
how to use a computer numerically controlled machine. It is currently
being used for designing and implementing a network protocol analyzer
tutorial, and WWW courseware.
Educators and students are finding out that designing
multimedia or media rich systems can be a long, new-lessons-learned
experience that can take months or even years. Although they
have the best of intentions, they start out with the latest multimedia
package and find that it may take a few months of squeezed-in
time to learn the basic functions so a modest multimedia system
can be crafted. They learn that their multimedia system does
not run on all hardware configurations and they find out too late
that the restful wilderness backgrounds of the presentation cause
the students' minds to wander from the material or make text difficult
Although educators and students may design and implement
a usable multimedia system, the system may become outdated and
not be structured so as to enable them to introduce new information
and delete old information later. If the system is developed
in hypertext, as when using the WWW, the hypertext nodes may be
linked together in a hodge podge network that leaves students
frustrated and confused as to whether or not they made it through
all of the material they should have and whether or not they learned
Many books and materials on instructional, hypertext,
and interface design exist, but educators and students may not
have time to read them all nor to decide which ones would be the
best in guiding them in the design and implementation of multimedia
instructional systems. They further may not have any formal education
in design for the purpose of implementing instructional systems.
They may be keenly interested in such issues, but simply have
not found the time from their other duties to pursue such issues.
A need exists for a simple-to-learn methodology to
help educators and students design and implement hypertext instructional
systems. The methodology should facilitate the division of the
material into hypertext nodes that are structured according to
key concepts in the material. The methodology should monitor
the design process with metrics to ensure the hypertext linkages
are tight within key concept boundaries, but loose between boundaries.
It should use a simple instructional design philosophy to enable
the hyperweb of instructional material to be augmented with cues
to assist the student in knowing what is about to be presented,
tests to assess the student's learning of the material, and activity
nodes to enable the students to practice the material. It should
include mechanisms to help the instructor validate and verify
the effectiveness of the instructional material, where the students
spend most of their time in the system, and how well the students
perform the activity and test nodes.
As a vehicle for showing the hypertext instructional
design methodology, a protocol analyzer tutorial is presented
which has already been developed without using the methodology
and used in class. The consequences of the development are shown
and then the hypertext instructional design methodology is shown
through the redesign of the tutorial. Finally, conclusions about
the methodology are presented and future work is considered.
At the University of Arkansas, computer systems engineering
students are keenly interested in networking and genuinely have
a thirst for the subject. To help to teach the students about
networking, a network protocol analyzer tutorial with a small
network protocol analyzer, called PROTAN, has been developed and
used in class  (more information can be found in ). The
tutorial tells students about protocol analyzers and their functions,
protocols, and the structure of PROTAN. The tutorial is written
in Ntergaid's Hyperwriter and runs under DOS on the PC. PROTAN
recognizes the TCP/IP suite on the Ethernet. PROTAN is written
in C and also runs under DOS on the PC.
The students' reactions to the tutorial were favorable
from a survey given to a graduate networking class. On a scale
of one (disagree) to ten (agree), their average response for agreeing
that the tutorial was useful was eight and for agreeing that the
tutorial added to their technical expertise was also eight. Seventy-five
percent of the students did not know about protocol analyzers.
They all agreed that the tutorial should continue to be improved
and material added to it.
A decision was made to move the tutorial to Windows
95 since DOS is no longer going to be supported. Since no funds
were available to upgrade to a new version of Hyperwriter, SIMPLE
was chosen to implement the new tutorial since it runs under Windows
95 and is free to educators. Although it was desired initially
to move the tutorial as it was in Ntergaid's Hyperwriter over
to SIMPLE, the structure of the tutorial did not lend itself to
future enhancement nor to easy conversion to SIMPLE. As with
many first efforts of design and implementation, much more was
now known about how the tutorial should have been structured.
Briefly, the structure of the tutorial is as follows:
The first screen allows the user to take a hypertext link into
screens entitled Read Me First, Protocol Analyzer,
PROTAN, Discussion of Code, Glossary, and
Hypertext. From the first screen, all links are structured
hierarchically and may lead the user down a path as long as seven
nodes as shown in Fig. 1. Each screen may be from half a page
to typically two and a half pages long. One screen is 6 and a
half pages long and the Glossary screen is eleven and a half pages
Adding nodes to a hierarchical structure is not very
difficult so that did not present a problem. Adding material
to nodes that were more than one page long simply made them longer.
Forming new links off the nodes did not seem to offer a very
good solution either. What was needed was to restructure the
material into the key concepts that students needed to learn and
to place supporting material into the hyperweb for this learning
to take place.
The methodology chosen for the redesign of the tutorial
is Adams' hypertext instructional design process  since it
is easy to learn and to use. It is also a complete process starting
from scratch and going through implementation and evaluation.
Both ease of use and completeness are needed to ensure educators
and students consider all factors from conception to implementation.
The methodology goes through several stages  in
helping the designer implement a multimedia system from scratch.
First the requirements stage enables the designer to focus upon
the key concepts to be presented in the material and produces
a graph of the overall structure of the system. The specifications
stage then successively refines the graph into the hyperweb structure.
The implementation stage takes the graph and implements it in
the chosen hypertext system. The entire process is undergirded
by validation and verification of the stages to ensure the key
concepts have been presented effectively.
III.A. Requirements Stage
The requirements stage focuses on the process of
determining the scope of the system entailing extensive analysis
of the subject matter to decide what information should be included
in the system and how the concepts will be grouped and linked
together. To facilitate this process, Object-Oriented Text Decomposition
(OOTD)  is used and provides a systematic method for decomposing
subject material into conceptual components. OOTD uses natural
language to communicate the information's structure and relation.
It utilizes top-down decomposition methods and concept-mapping
applications of Ausbel's learning theories  to produce a hierarchy
representing the information in a modular form. The steps are
Utilizing these steps, the protocol analyzer tutorial's
thesis sentence with key concepts bolded would be:
"Network protocol analysis is the process of
capturing network packets in real-time for the purpose of network
monitoring, specific condition testing, filtering
based on specific criteria, and data collection and analysis."
The expanded paragraph would be:
"Network protocol analysis is the process of
capturing network packets in real-time for the purpose of network
monitoring, specific condition testing, filtering
based on specific criteria, and data collection and analysis.
Network monitoring may use a graphical display to show
traffic, collisions, and bad frames. Specific condition testing
allows certain packets to be sent to check the operation of network
hardware. Filtering based on specific criteria enables
certain packets to be monitored based upon their addresses or
even their lifetime. Data collection and analysis allows
network traffic to be captured to a file and 'replayed later'."
The relationship between the key concepts and the
paragraph theme are as follows:
Each key concept then is expanded into its own thesis
sentence and paragraph. All key concepts are decomposed as far
as desired and are connected into an OOTD graph through their
relationships as shown in Fig. 2. The OOTD graph gives an overall
linking structure to the hyperweb. Each node in the OOTD can
itself be a hyperweb as well.
III.B. Specifications Stage
The specifications stage takes the OOTD graph and
refines it into a structure suitable for implementation in a hypertext
system. The first step in the specifications stage is to determine
the first and second order links in the OOTD graph to produce
a system flowchart as shown in Fig. 3. The first order links
represent the links the student should take to learn the material
and may even represent the ordering of a textbook's chapters and
section headings. The second order links are conceptual in nature
and serve to connect related material if desired. Then the system
flowchart is refined into the conceptual graph shown in Fig. 4
where key concepts are grouped into sets of nodes supporting a
single instructional theme. The groups may be tightly coupled
within themselves, but should be loosely coupled to outside groups.
The conceptual graph is augmented with additional
nodes through using Gagne's Events of Instruction  shown in
Fig. 5 to enable the designer to consider instructional and administrative
issues. As shown in the figure, to gain attention, a title screen
may be used. To inform the student of the lesson's objective,
an introduction segment may be used to present an overview, lesson
materials, lesson objective, and terminology list. In the tutorial,
review screens may stimulate recall, information screens present
material, and activity screens along with feedback provide learning
guidance. Practice screens review the material, test screens
elicit performance, and performance reports assess performance.
The content flowchart is the result of using Gagne's
Events of Instruction to augment the conceptual graph and is shown
in Fig. 6. All links are bi-directional in the flowchart, but
those to the test nodes which must be one way to keep the student
from exiting before finishing the test. The flowchart should
be verified to ensure that all nodes can be reached and concept
groupings are tightly coupled through measuring the centrality
of key concept nodes . The flowchart may also be given to
content experts to check the validity of the material.
III.C. Implementation Stage
Now the instructional designer can take the content
flowchart and implement it in the system of choice. It is also
at this point that the interface screens are designed and implemented
(they might have imposed a premature structure on the hyperweb
if designed and implemented earlier). The screens should be implemented
in a consistent manner with no more than three to six colors per
screen and to minimize user mouse movement and keyboard effort.
For example, instructional material and navigation links should
be placed in a common area on the screen.
The completed system should be reviewed by subject
matter experts to ensure completeness and that all links can be
traversed. Once again, centrality of the key concepts should
be verified. The system can be used by a limited number of students
to work out minor problems before general usage.
The methodology is designed to be easy to use and
represent a complete modular engineering design process. It is
a synthesis of research performed in the fields of software engineering,
computer science, and education. It enables designers to focus
on building systems that will be expandable by adding more key
concepts into the hyperweb, maintainable and amenable to modifications
as curriculum needs change via key concept node alterations,
and reliable through verifying links and instructional effectiveness.
It enables the instructional system to be visualized before implementation
to allow design faults to be caught before the final system is
Another aspect to the methodology is that since it
can be learned quickly, students can use it during a semester
for semester projects and also can benefit from designing their
own instructional systems for other students. Both educators
and students can learn the benefit of concentrating and dividing
material into key concepts to help them understand and teach the
The hypertext instructional design process has been
used to construct a tutorial for teaching machinists how to use
a computer numerically controlled machine, a Novell NetWare 3.12
tutorial, and an Artisoft LANtastic 6.0 tutorial. It is currently
being used to implement the protocol analyzer tutorial, two robotics
tutorials, a JAVA WWW tutorial, a Novell NetWare 4.0 tutorial,
and instructional material on the WWW. In all cases, individuals
using the process have produced more effective and modifiable
tutorials than if they had not used it. The process causes them
systematically to address issues, such as interface design, how
much material to put into a node knowing the node should only
have as much as one screen of text, keeping the hyperweb shallow
and broad, and how best to divide the material into effective
lesson presentations. They also do not consider it a difficult
process to use.
The first step is to automate the hypertext instructional
design process to produce a skeletal or complete multimedia system
from the design. In order to make the best use of the time of
educators and students, they must be able to design and implement
almost at the same time. They consider it tedious to do the design
and then have to do the implementation afterwards. The implementation
will be done in SIMPLE and/or HTML since they are free to educators
and students who enjoy working with either of them since they
are easy to learn.
A convenient means for educators to implement multimedia
systems and track students' progress is SIMPLE, a multimedia development
system designed to pull together various media elements into one
whole. SIMPLE, written in Microsoft's Visual Basic and utilizing
Microsoft's Access database package, is capable of producing such
systems as Broderbund's MYST and is, therefore, powerful enough
for most educators' and students' needs. More important, it is
free to educators and students through the WWW from Texas Tech
University's Computer Science Department link in the College of
Engineering. SIMPLE, developed by educators, Marion Hagler and
Bill Marcy, for educators, can be learned in less than a week
for those familiar with computer systems and includes a log utility
showing the progress of students as they use the system. Log
utilities are usually only present in expensive multimedia systems
and must be hand-crafted on WWW systems.
The automated system can generate a SIMPLE database
or HTML files from the design. The system can also monitor the
design for the ability to reach all hypertext nodes and the centrality
of all key concept nodes. It can enable others to check the system
for instructional material validity before the tutorial is implemented.
It can allow designers to make changes to the system in the design
and then generate a new implementation. It can allow cross-referencing
to be performed from stage to stage to ensure all of the requirements
and specifications have been met.
The automated system will be written in a modular
fashion so as to allow other instructional design methodologies
to be used if desired. It may even allow other design methodologies
to be plugged in and used as well.
All terms know to be trademarks or registered trademarks
This work was supported in part by the University
of Arkansas College of Engineering and the Advanced Manufacturing
Many thanks to Marion Hagler and Bill Marcy for making
SIMPLE available and for continuing to support it.
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Design Principles and Graphical Design Techniques to Computer
Aided, Hypertext Based Instruction. Master's Thesis, Computer
Systems Engineering, University of Arkansas, Fayetteville, AR,
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Ethernet Networks with a Hypertext-Based Tutorial. Master's
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Fayetteville, AR, 1995.
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Susan A. Mengel received her Ph.D. in Computer Science
from Texas A&M University in 1990. She joined the Computer
Science Department at Texas Tech University in 1996 as an Assistant
Professor. Previously, she was employed in the Computer Systems
Engineering Department at the University of Arkansas in Fayetteville.
She is currently developing multimedia tutorials to help students
learn networking and robotics concepts. She also has interests
in object-oriented software engineering and intelligent systems.
She has been chosen as a NASA Summer Faculty Fellow at the Jet
Propulsion Laboratory in Pasadena, CA. She is a member of IEEE,
ACM, International Neural Network Society, and ASEE. She is active
in Engineering Education being the Newsletter Editor of the ASEE
Educational Research and Methods Division. She may be reached
CPT William J. Adams is an Instructor at the United States Military Academy. CPT Adams is an active duty Signal Corps officer with over ten years of service. He has a Bachelor of Science degree in Computer Engineering from Syracuse University and a Master of Science in Computer Systems Engineering from the University of Arkansas. He is a member of Upsilon Pi Epsilon, AFCEA, and the ACM. His research interests are primarily focused on hypermedia development and integrating hypermedia into instructional programs. He may be reached at email@example.com.