1. A Distributed Open Asynchronous Information Access and Management Environmentby
Mehmet Sen
EECS, Syracuse University
Advisor: Geoffrey C. Fox
November 30, 2000
12/31/2018

2. Outline Research & Problem Definition Some Contributions
Related Work (Standardization efforts,…)
A Software Architecture
Middle-tier Services
Front-tier Interfaces
Related security issues
Issues of proposed distributed system
Summary of Contributions
Conclusions
12/31/2018

3. What Is Our Research?
Designing: a multi-tier architecture for commodity computing.
Studying: the basic needs for a learning management system (LMS).
Applying: our design as a LMS.
Analyzing: the results both from building the architecture and from practical usage.
Proposing: a new computing framework model based on our lessons.
12/31/2018

4. Motivations Why are we doing this research?
Learning technologies are improved in last half-decade as well as technologies in other fields.
Commodity technologies are shaping learning technologies. (Complete web-based learning environments).
Technology applications in learning
Prior to 1998
1999
2000
Primitive applications of technology
STANDARDS APPEARING
Widespread Technology Tries
12/31/2018

5. Basic Needs and Problems Encountered Leading to Our Research:
Distance learning: difficulties that off-campus geographically distributed students have in following a web-based course.
Providing a complete on-line course environment for on-campus students: benefits of keeping student records in a trustable, easily-securely accessible database environment
Technical overload of web course preparation: lists, accounts, home pages, add-drop, surveys many hours of human effort because of no automated environment.
Grading with distributed teaching teams.
Online progress tracking: Online grading, surveys and quizzes, on-the-fly generated evaluation reports, etc.
12/31/2018

6. Need for Further Research Why do we need to research, is there difference?
This area (educational technologies) is in its infancy, we do not have yet next generation sophisticated web-based learning environments.
There is a collapse to construct fundamentals on an educational architecture, or computing architecture between educators and computer scientists.
We are not expert in education research, but it seems that technical architectures are weak, i.e., old.
12/31/2018

7. Major Contributions
Scientific and architectural view of asynchronous support in distance education.
The multi-tier architecture model for a distributed, open, asynchronous information access and management environment.
Artifact: architecture’s prototype: virtual classroom manager (VCM.).
Lessons learnt and further/future research.
A new computing framework model based on our lessons.
12/31/2018

8. A Compact Taxonomy of Learning Technologies
Content preparation
Content delivery:
Asynchronous
Synchronous
Information management
12/31/2018

9. Advances in Learning Systems What is done as learning systems?
Development of academic and commercial sources
WebCT, Blackboard, Lotus Learning Space, WebMC … (mainly interesting as authoring strategy)
Tango, WebEx, Centra, Placeware (delivery)
Standardization Efforts: (examples)
IMS (Instructional Management Systems)
DoD; ADL (Advanced Distributed Learning ), AICC (Aviation Industry CBT Committee)
IEEE LTSC (Learning Technology Standards Committee)
ARIADNE (Alliance of Remote Instructional Authoring & Distribution Networks for Europe)
12/31/2018

10. IEEE LTSA (architecture) by Learning Technology Systems Consortium (LTSC)
V C M
framework for general learning technology systems (to understand sys.)
Neutral, promotes interoperability in 5-10 years
12/31/2018

11. Traditional classroom mapped to LTSA system components
12/31/2018

12. VCM mapped to LTSA system components
12/31/2018

13. How Do Standards Come Alive?
IEEE, ANSI, ISO: Accredited Standards
LTSC (P1484)
Liaison
Liaison
Liaison
Education & Learning Technology Orgs: AICC, ADL, IMS, ARIADNE
12/31/2018

14. Standardization Efforts in Learning Technologies I
Course content preparation;
SCORM (Sharable Courseware Object Reference Model) by DoD ADL (Advanced Distributed Learning)(1/00)
Content Packaging by IMS (Instructional Management Systems) (2/00)
Content Management by IMS (just starting)
LRN (Learning Resource Interchange) by The Microsoft (01/00)
Content Play Rules [Ostyn]
UFI Content Interworking Schema [FD-UFI]
12/31/2018

15. Standardization Efforts in Learning Technologies II
Metadata:
IMS Metadata for describing learning resources
IEEE LOM Learning Object Metadata describes learning content cataloging information (basically proposed by IMS and ARIADNE)
12/31/2018

16. Standardization Efforts in Learning Technologies III
Evaluation & Assessment;
IMS Question and Test Interoperability Specification (/00) (provides proposed-standard XML language for describing questions and tests. )
12/31/2018

17. Standardization Efforts in Learning Technologies V
Human Information Management
Public and Private Information (PAPI) for Learners Draft Standard for Learning Technology (previously known as Personal and Performance Information)
Logical categories of learner information
12/31/2018

18. Further Organizations
PROMETEUS (PROmoting Multimedia Access to Education and Training in EUropean Society)
The Dublin Core:
Metadata for discovering Electronic Resources
author-generated description of Web resources,
Simplicity + Semantic Interoperability+International Consensus+Extensibility
Metadata Modularity on the Web: The World Wide Web Consortium (W3C) works on architecture for metadata on the Web.
The Dublin Core's Resource Description Framework (RDF) is for different metadata needs of vendors and information providers.
12/31/2018

19. Open Standards & Technologies
HTML, DHTML, JavaScript, JSP
XML, XSL, RDF, DOM, SAX
Java, Servlets,
HTTP, IIOP, COM
DCOM, CORBA, EJB, RMI
12/31/2018

20. Open technologies & Learning Standards
Will(may) provide us:
Integration of leading systems in one big environment
Easy management of systems
Rich set of properties such as discoverability, accessibility, interoperability, reusability, durability, extensibility, quality, modularity, simplicity, etc.
12/31/2018

21. What Standards and Current Practices Miss ?
Well designed architectures
Some standards or models may dependent on current practices’ scope.
Some standards or models may not be long-lasting (or equivalently problematic in long term)
12/31/2018

22. Our Multi-Tier Architectures Our very first short termed architecture
HTML+JavaScript
OWA, or
WOW+wowstub
Web
Server
Database
Bridge
Database
Connection
script
Database
client
Oracle Web Server
12/31/2018

23. Current architecture System Web Server client Legacy Systems Manager
Object
Providers
High
Level
Request
Brokers
Services
Legacy Bridge
Database
Bridge
Database
client
Database
Bridge
Database
Bridge
Database
Bridge
12/31/2018

24. Legacy Systems Web Server Database Represents Web Object SystemWO
Represents Web Object
Legacy
Systems
Web
Server
System
Manager
High
Level
Object
Request
Brokers
Object
Providers WO
Services
Legacy Bridge
Database
Bridge WO
Database WO
Web
Object
Web
Object
Web
Object
Web
Server
System
Manager
Object
Providers
High
Level
Request
Brokers
Services
Database
Bridge
12/31/2018

25. Multi-Tier Architecture(implementation view)
12/31/2018

26. Issues on Web Objects
There are various common object models, like COM, CORBA, Java, Web, etc..
Choosing an implementation model is not important as long as XML is the language to communicate between systems.
We preferred a Web Object Model, served as XML documents on the Web
12/31/2018

27. DB to WEB With XML (Object Service View)
HTTP, IIOP,
RMI, DCOM,
TCP/IP Socket
Request
Services
Web
Server
DOM
Object
Provider,
Broker
JDBC DB
Servlets
XSL
Templates
XML
Parser
HTTP
12/31/2018

28. Features of VCM Multi-tier architecture
Commodity user interfaces, and administration.
Asynchronous collaboration of users, e.g.,
supervisors, instructors, co-instructors, TAs, students, guests, and administrators
Security mechanisms;
SSL, user authentication, access privileges, ACL, browser protections, etc.
Virtual university records for
students,
courses,
Assignments
Faculty,
12/31/2018

29. Features of VCM II
Assessment tools: online grading, online surveys, statistics, etc.
Virtual university services, e.G.,
Online course registration, post-office & automated mail lists, password assignment, file uploading, class lists, surveys, quizzes, grades, performance assessment.
System services & legacy systems connections.
Web based configuration.
Continuous support, long-term referencing to the records, e.g., For statistics,
The entire architecture is implemented based on the concern of usability, performance, portability and easy installation to any machine.
12/31/2018

30. Typical Features for Public
List, browse, update, add, remove records, etc.
Automatic linking of web page references from various places to the course home page.
Students can online-register, access and modify.
Students can administer their virtual directories and personal accounts.
Students can take online quizzes, surveys, etc.
Access to enhanced class web links collected.
Students can access performance records, post office, upload homework files,
Automatic evaluation of results.
Performance tuning.
12/31/2018

31. 12/31/2018

32. Database Schemes performances Students answers courses grades
questions
assignments
Surveys
exam_grades
quizzes
layouts
Users
Questionnaire
12/31/2018

33. Middle-tier Services Learner Object Service(s)
Course Object Service(s)
Assignment Object Service(0s)
Quiz Object Service(s)
Survey Object Service(s)
Performance Object Service(s)
Supervisor Object Service(s)
AssessmentNugget Object Service(s)
12/31/2018

34. Learner Objects (Logical Information Categories)
Learner personal information
Learner relations information
Learner Security information
Learner preference information
Learner performance information
Learner portfolio information
12/31/2018

35. Learner Objects (information access controls)
Private information  personal information, …
Restricted access  performance information, learner relation information, …
Levels of public access  preference information, relations, security
Availability for applications  preference, relations, performance,
Availability for administration  personal, performance, …
Availability for humans  learner portfolio, …
12/31/2018

36. Course Objects (related study: SCORM)
12/31/2018

37. VCM Course Objects default = one element required;
“?” = zero or one (optional);
“+” = one or more required; “*” = zero or more required
12/31/2018

38. Assignment Objects
12/31/2018

39. Assignments Online Grading & Statistics
List, browse, add, remove, modify, publish
On-line grading
Access to grades is secure and private.
Privileged levels of accessing performance records
Various grading options and interfaces.
Automatic evaluation reports
Feedback information to individual students.
12/31/2018

40. Assignment Submission: NPAC Virtual File Manager
used for uploading homework files into virtual directories in server side, and directory-file manipulations.[VPL]
12/31/2018

41. 12/31/2018

42. 12/31/2018

43. 12/31/2018

44. Quiz Objects (IMS model)
12/31/2018

45. Quiz Objects (VCM Model)
12/31/2018

46. A Taxonomy of Question Types by IMS
12/31/2018

47. Response-Type Specific
Quiz Object
Repository
(XML codings)
XSLT
Rendering
Generic
Assessment
Engine
XSLT
Response-Type Specific
Assessment
Candidate
Transferable, editable,
remotely accessible
XSL codings
LMS specific, final codings in Java, C, C++, etc.
12/31/2018
QUIZ SERVICE

48. 12/31/2018

49. 12/31/2018

50. 12/31/2018

51. AssessmentNugget Objects
12/31/2018

52. Survey Objects
12/31/2018

53. Performance Objects
12/31/2018

54. 12/31/2018

55. Supervisor Objects
12/31/2018

56. System Administration Objects
12/31/2018

57. Front-tier Customizable Open Interfaces
We experimented with two kind of template structures;
Pure HTML page with inserted variable tags inside;
simple
very easy to edit
XSL templates to render XML objects;
more capable,
sophisticated for editing but now lots of commercial tools are available.
Both templates are editable by the final system users
12/31/2018

58. 12/31/2018 msen@ecs.syr.edu <html> ……………
<body bgcolor=white>
<b><input type=button value="LIST" onClick="list()"></b>
<a href="$help/user.html" target=help><img src="$images/mans.gif" border=0 align=ABSCENTER></a>
<script language="JavaScript">
//<record>
document.write("<tr ><td>");
if ("$url"=="")
document.write("<img src=$images/homeempty.jpg border=0 align=center>");
else document.write("<a href=$url target=hp><img src=$images/homefull.jpg border=0 align=center></a>");
document.write('</td><td><a href="frame.html?unum=$unum&comm=FRAME&framecomm=SHOW&file=browse.html&gslogin=$gslogin" ><b> $la
stname, $firstname $midname </b></a></td></tr >');
//</record>
</script>
<font size=-1><i>NPAC</i></font>
</body>
</html>
12/31/2018

59. XSL
12/31/2018

60. Security Issues of an Open Access Environment
Communication Channel Security
Front-end Security
User Authentication
User Access Lists
User privilege Levels (8 categories)
Presentation Security
Uniuque and random session key, timeout-windows, no-caching,
12/31/2018

61. Lessons on Interoperability Issues of Distributed Components
Integration of services (collection of services=different systems) is necessity for
Next-generation, large-scale distance courses, or in any other field.
We need one big container (= framework) to hold others such as CORBA, COM, EJB
12/31/2018

62. Software Components
The next software model after object-oriented paradigm, however,
Components (objects) are only usabe in their own framework
Plug-and-play properties are not satisfied (analogies are not true, e.g. similar to hardware comp., lego, etc.)
Non-professionals want to participate in development.
12/31/2018

63. Framework of frameworks
12/31/2018

64. Distributed Web Object Service Model
May play equivalent role of component model,
Properties need to be provided are:
Discoverability,
Accessibility
Interoperability
Reusability
Durability
Manageability,
And More…
Note that object definition is not the one in OOP.
12/31/2018

65. Possibility of such framework
Technologically possible,
There are samples; WWVM, WebFlow, Gateway, and HTML.
HTML is non-computational model providing all the properties.
12/31/2018

66. Interactions of systems
Currently we have
Machine-to-machine interaction (TCP/IP, HTTP, IIOP, COM)
Machine-readable (XML)
Human interpretable
We need
Machine-understandable content
Note that XML is common language, systems are thinking in other languages like me.
12/31/2018

67. Solutions;
Agreeing on common standards of object formats (syntax and semantics)
Agreeing on semantics of general properties of objects,
Agreeing on semantics of specific field objects, e.g. Learning System Objects
We will get interoperability and reusability.
12/31/2018

68. RDF Model (simple example)
Properties of educational objects, i.e., metadata, helps to locate, access, use and manage Web objects.
Metadata includes various aspects of current document like copyrights, price, pedagogical info, classification, rendering info, history, relation and links to others.
RDF (netrual, resource+property+statement,
resource
owner
author
property
Alice
name
value
John Smith
12/31/2018

69. A Description Framework of Web-Objects (Learning Objects)
Portfolio Info Object
Programming:
Game Applet
Assignment Report
Game Metadata ….
Recruiter Metadata
LMS Metadata
CLIENTS
Assessor
Recruiter
Child
METADATA CATOLOGING
12/31/2018

70. Adapter Adapter Adapter NameSpace: LMS NameSpace:Science
NameSpace:Government
NameSpace:
Science
Adapter
Adapter
NameSpace: Entertainment
Adapter
12/31/2018

71. Global Object Service Locators LMS 1
Course Content
Info. Services 6 5 7 1 2 8
Personal Info.
Services
Client
(LMS Application) 3 4
LMS
Learning Management System
Discoverability,
Durability,
(Manageability)
First Object Service Request
Second Object Service Request
12/31/2018
LMS 2

72. Web-Object Characteristics
Service
Web Object
<xml>
<Control>
………
</control>
<information>
</information>
</xml>
Control
Process
CLIENT
(Web Object Service)
Manageability;
Programming capabilities
Internal Services
12/31/2018

73. Contributions
Scientific and architectural view of asynchronous support in distance education.
The multi-tier architecture model for a distributed, open, asynchronous information access and management environment.
Artifact: architecture’s prototype: Virtual Classroom Manager (VCM.).
Lessons learnt and further/future research.
12/31/2018

74. Contributions 2 Our generic architecture is applicable to other fields
Our information management environment is applicable to any human-record keeping application development.
Designed a new web-object service architecture as a support for our new computing paradigm
Proposed a new computing paradigm through object web services. (discoverability, accessibility, interoperability, reusability,durability,manageability, …)
12/31/2018

75. Contributions 3 Designed inter-technology cooperation methods,
Proposed inter-disciplinary interaction methods,
We introduced new object types to LMS
We gave a complete LMS picture for learning technology developers
We illustrated how to use a large set of technologies for a single system.
We illustrated how to use a set of systems for a single purpose
We used objects as containers of others
12/31/2018

76. Contributions 4 Lessons:
Individual technologies, their computing frameworks and platforms are no longer important
Integration of systems will make them much powerful
One system or technology is not enough to fulfill large scale applications
Both professionals and non-professionals involved in the environments presented by a rich set of commodity technologies.
Technologies ( more realistically services) should be manageable by both professionals and non-professionals. (should be easy)
Analogies are not valid between software and other sys.
12/31/2018

77. Contributions 5 Lessons:
Practical social issues should be considered in application development, I.e, LMS develop.
Some standards are too detailed, may not be long lasting
Back-end tools, or legacy systems, are not important
They can be utilized with full functionality
Yet we can offer new computing models on top of them
However, modern backend tools may be more functional, e.g., XML Databases
12/31/2018

78. My advisor Dr. Geoffrey Fox Dr. Nancy McCracken
Thank you
I thank you very much
My advisor Dr. Geoffrey Fox
Dr. Nancy McCracken
for their great help to obtain my PhD.
12/31/2018

79. Resource Description Framework
RDF is an abstract data model
Cataloging(&describing collections)
intelligent agents
resource discovery; search service component
describing collections of pages that represent a single logical "document“
RDF consists of three different types of objects
Resource: anything with URI
Property: a relation or an attribute used in describing resources
Statement:resource+property+value
12/31/2018