1. Introduction
We developed a distributed-open asynchronous information access environment
where users have web-based interfaces from different locations through a
complete security mechanism and user authentication interface integrated to
commodity interfaces. The environment provides asynchronous collaboration of
supervisors, instructors, co-instructors, TAs, students, guests, and
administrators through the Web Browsers. Distributed students can register
on-line for the courses and get services like password assignment, post
office & automated mail lists, file uploading, pictured class lists,
surveys, grades, evaluations, performance assessment, and other account
administration. The student records and their performance records are
planned to be kept in a database continuously that provides a base for a
virtual university student services. Students performance pages include
their grades, grader comments, averages, expected grades, failures and
suggestions, etc. A student can access his performance page, at any time
from any where having web access, and can include his resume at job
applications for more reliable evaluations.

Besides the convenience of online grading and submitting the grades to the
students, instructors use the environment as a technical services provider
for the course preparation and as an assessment tool during the semester, or
later as a long-term reference. The graders can see various statistics about
the students at any time while grading from a web browser. A categorized
questionnaire database is useful for online surveys and quizzes. Preparing
class surveys provides tracking of the students' progress, understanding of
course quality, and increased adaptability to student needs. Possible
customizations of grades brings more flexibility to grading.

The environment also presents an user friendly administration interface on
the web. A server administrator can tune the performance and change the
configuration from any web browser connected to the Internet network.

Our architecture design considered a broad perspective of educational
environments. Similar feature sets exist in other course management systems
such as WebCT [WebCT]. The architecture of WebCT is based solely on the Web
Server and file system. While this is suitable for many situations, our
architectural design is driven by the need to incorporate commodity
databases as in PAPI [PAPI] specifications on data interchange formats, and
other advanced web systems used by our professors in developing course
materials such as WebWisdomNT [WebWisdom].

	2. Basic Needs and Problems encountered leading to the project
In our experience with distance learning, we realized that especially the
outside distributed students had difficulties in following a course
presented with recent web technologies. A new complete integrated
environment needs to be presented to the outside registered students to make
them feel like they are attending a virtual university, and also benefits
the on-campus students with a complete course environment on-line. Not
having the student records in a trustable, easily-securely accessible
database environment is a complete disadvantage for both on and off-campus
students. Specific web-based interfaces should allow users to access certain
information,perform related operations, and store the results in a stateful
environment.

The team offering the courses also felt overloaded by the work of technical
class preparation. Construction of class lists, email lists, making Unix
accounts, listing student home pages, submitting passwords to students and
keeping track with add-drop students, measuring class level with surveys for
different types of courses needed many hours of human effort because of no
automated environment. Issues like grading became a problem with distributed
teaching teams. Furthermore, online progress tracking, having a categorized
questionnaire databank, automatically generated evaluation reports, and
similar services became a need more than a luxury.

	3. Features
We designed the student records system specifically to offer the following
functionalities through the Web:
Menus Image URL http://carver.npac.syr.edu:3768/users-docs/msen7/paper/userstudentmenus.gif

	3.1 Course Records
One can see the courses listed to use operations like browse, update, and
delete on the present courses, or new courses can be added. Instructors can
prepare surveys to be filled by on-line registering students.
	3.2 Student Records
Staff users can see the students registered in each course listed. One can
create new students, browse, update, and remove students. Students can
access their own records, which they get by on-line registering to the
courses. They can always see their performance records, use the post office,
upload homework files, administer their virtual directories and personal
accounts, see enhanced class Web links collected, and use other tools.
	3.3 Assignments & Grading
The team offering courses to students can make new assignments through the
web interfaces and specify grading information about the assignments such as
weights, published URLs, etc.

The on-line grading provides an asynchronous collaboration between
distributed staff team members which is invisible to the students. Students
may see their grades online, securely and privately after they are published
by graders. The grading interface contains different information and
comments depending on the security level of the accessing person; grader,
students, assistants, instructors, supervisors, parents, etc. The grader may
use various interfaces, has different grading alternatives, e.g., numeric,
countless customized word grades, etc., and feedback information while
grading, e.g., averages, ranks, etc.
Image URL http://carver.npac.syr.edu:3768/users-docs/msen7/paper/grading.gif
	3.4 File Manager
The NPAC Virtual File Manager is integrated in the environment for uploading
homework files into virtual directories in server side, and directory-file
manipulations.[VPL]
Image URL http://carver.npac.syr.edu:3768/users-docs/msen7/paper/filemanager.gif
	3.5 Surveys & Quizzes
Through the web interfaces, instructors can prepare surveys & quizzes for
students at any time during the course offered. A categorized question bank
is kept in the database to enable re-use of previous questions. Questions
may be distributed into different categories, and presented in a logical way
to the students independent of their preparation time. Beyond the regular
quizzes, different aspects of quizzes - from student-self evaluation quizzes
to pop-quizzes in class time - are currently in progress. The survey results
are automatically evaluated and immediately presented to supervisors on
their browsers. By using the surveys and quizzes the understanding level and
expectations of the class may be measured, and the performance of the class
can be improved.
Image URL http://carver.npac.syr.edu:3768/users-docs/msen7/paper/surveyresult.gif
	3.6 User records
In addition to the student, accounts are kept in the system for instructors,
co-instructors, supervisors, super users, TAs, graders, administrators,
browsers, other system administrators, etc. These records contain personal
information about the users and their access privileges. The security issues
about different levels of users will be discussed later.
	3.7 Services and legacy systems connections
One of the important characteristics of the project is that it contains many
services automated in its environment. The load of the staff offering courses in NPAC relieved considerably. Besides these services, there are
other services directly offered in the environment, like its own post-office
categorized email lists. Administrators can do performance tuning and
configuration changes from an easy front-end interface. The access logs of
students using web-based materials are kept for future reference and
assessment.
	3.8 Security Issues
Student records are among the most private kinds of information in
education. Because of its exposure to the public over the Internet, the
whole environment is subject to attacks to capture, to alter, to destroy the
private information. For the sake of completeness, complete security should
be inserted into the architecture. We solved the security issues under the
following categories:
Image URL http://carver.npac.syr.edu:3768/users-docs/msen7/paper/security.gif

3.8.1 Communication channel security: Currently, we are using the technology to
secure the communication channels over a public network by using public key
cryptography in the SSL protocol for securing the transfer of information
over the Internet.

3.8.2 User authentication: Like many computer operating systems, a user
authenticates himself by entering a user login id and a secret password
known solely to himself and the system.

3.8.3 User access lists: The second part of the authentication mechanism is
keeping access lists for the users. All the users are restricted only to
access to the allowed part of the database, HTML pages. Access lists can be
easily manipulated in the user records interface, simply by carrying present
course names to the access list box.

3.8.4 User privilege levels: Since privacy issues are most important in such a
system, user password authentication and access lists are not enough to keep
privacy by themselves. After those steps, a user must have powerful enough
privileges to access, delete, update some records, or to see HTML
information pages.

3.8.5 Presentation security: One of the challenging issues in the security is 
not the communication security but keeping the data private after the data
is transfered. It is highly possible that students may view their grades and
other private records in a public cluster. Although it is not possible to
provide complete security at this level, we improved different strategies to
make the risk as low as possible; the SSL server prevents browser caching in
general, timeout clocks destroy the windows, the new unique id given by each
login, with expiration time, prevents using same URL and stealing passwords,
etc.
	3.9 HTML Editable User Interfaces in template library
All the user interfaces are presented through the WEB browsers, and they are
also kept as HTML-like files in a template library separated from the
implementation and the database records. One can easily edit user interfaces
as HTML files without any technical knowledge of the environment. Also using
various style sheets for different users is possible.
	3.10 Easy system administration
A front end menu is prepared for the administrators, who are configuring the
connections like, JDBC-Database connectivity, and tuning up the performance,
etc. Any third party, who wants to use the project for themselves, can
easily use the project just by using user friendly front-end guides without
any deep knowledge of components without having highly skilled computer
experts.

	4. Architecture and technologies involved
The entire architecture is implemented based on the concern of usability,
performance, portability and easy installation to any machine. The involved
technologies include HTML, JavaScript, Java, JDBC, SQL, SSL and a limited
amount of Perl for specific local legacy systems. The below figure illustrates
the architecture of the environment;
Image URL http://carver.npac.syr.edu:3768/users-docs/msen7/paper/architecture.gif

The architecture is a multi-tier architecture. In general it can be seen as
a three-tier architecture. The more layers in the middle tier are especially
designed in semantics of modularity and easy integration with other related
projects.

The user interface is completely presented as an commodity interface. All
the data access, and functionality is managed through the client browsers.
The communication with the outside world is provided through dynamically
produced HTML pages by the servlets. The communication channel is secured
with SSL to complete other inside security mechanisms as previously
mentioned.

In the middle tier, the main intelligence of the environment is placed
hierarchically. The first level contains the high level functionalities to
talk with the clients and to perform the operations in a more advanced level
without considering the low level system dependencies like database
connectivity. The relational database records are considered as the objects
at this level. The second level mainly serves as a cache memory to database
objects. The cache mechanism provided performance increases by decreasing
accesses to the database for each operation. The objects in the cache are
defined as the objects which are kept in a single relational database table
row entry and the related methods to perform on them. The last level
performs low level operations like connecting to the databases and
performing database related operations. Each independent type of tables
like, students, users, courses, etc., has an associated class. The last
layer in the architecture is the database back-end. Since the implementation
is done with Java, any suitable database supporting basic SQL standards can
be chosen and the database access can be forwarded to the selected database
through a JDBC bridge update in the front end options. The parser
dynamically produces HTML user interfaces through the template library
stored in outside editable HTML-like files. Finally, the architecture
includes the legacy systems through a cgi module.

	5. Conclusion and Future Directions
NPAC's student records database environment has been used by many students,
about 450, and staff in the last two years. It has evolved with professional
experience and new needs both by on and off campus course offerings[SC98].
The environment keeps a rich set of online available tools useful in
education. Distributed students from Missisipi, Boston, Georgia, Houston,
and Syracuse have successfully  registered on-line for the same course 
offerings in the environment.

The implementation is entirely written in Java in a portable fashion.
Another educational organization has also installed it. Its layered and
modular architecture provides easy upgrading and integrability with other
environments, e.g., high level sharing database records. The environment
provides easy server administration and configuration through the Web
additional to its convenience for users.

Currently we are developing new assessment tools having a new horizon using
data mining techniques on combination of environment logs and other
synchronous and asynchronous resources logs. We are planning database
integrations with our other current projects through XML. Using DHTML in
user interfaces is another issue.
 
	Acknowledgments: We would like to thank S. ElMohamed and M. Ispirli 
for their feedback in various stages of this project.

	6. References
[VPL] K. Dincer and G. C. Fox, Using Java and JavaScript in the Virtual
Programming Lab: A Web-Based Parallel Programming Environment, in
Concurrency: Practice and Experience Journal, June 1997.

[HPDC-6] K. Dincer and G. C. Fox, Design Issues in Building Web-based
Parallel Programming Environments, in Proceedings of the Sixth IEEE
International Symposium on High Performance Distributed Computing (HPDC-6),
Portland, OR, August 5-8, 1997.

[SC98] David E. Bernholdt, Geoffrey C. Fox, Roman Markowski, Nancy J.
McCracken, Marek Podgorny, Thomas R. Scavo Syracuse University | Debasis
Mitra and Qutaibah Malluhi, Jackson State University, Synchronous Learning
at a Distance: Experiences with TANGO, SC 1998.

[WebCT] Murray W. Goldberg and Sasan Salari, "An Update on WebCT
(World-Wide-WebCourse Tools) - a Tool for the Creation of Sophisticated
Web-Based Learning Environments", Proceedings of NAUWeb '97 - Current
Practices in Web-Based Course Development, June 12 - 15, 1997, Flagstaff,
Arizona.

[PAPI] Frank Farance (edutool.com), James Schoening (US Army),Public and
Private Information Specification, http://www.edutool.com/papi/papi-500.html

[WebWisdom] Geoffry C. Fox, URL http://www.npac.syr.edu/users/gcf/wisdom/help/