A Distributed Open Asynchronous Information Access and Management Environment by Mehmet Sen EECS, Syracuse University Advisor: Geoffrey C. Fox November 30, 2000 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

A Compact Taxonomy of Learning Technologies Content preparation Content delivery: Asynchronous Synchronous Information management 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

Traditional classroom mapped to LTSA system components 12/31/2018 msen@ecs.syr.edu

VCM mapped to LTSA system components 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

Legacy Systems Web Server Database Represents Web Object System WO 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 msen@ecs.syr.edu

Multi-Tier Architecture(implementation view) 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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Database Schemes performances Students answers courses grades questions assignments Surveys exam_grades quizzes layouts Users Questionnaire 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

Course Objects (related study: SCORM) 12/31/2018 msen@ecs.syr.edu

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

Assignment Objects 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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Quiz Objects (IMS model) 12/31/2018 msen@ecs.syr.edu

Quiz Objects (VCM Model) 12/31/2018 msen@ecs.syr.edu

A Taxonomy of Question Types by IMS 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu QUIZ SERVICE

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AssessmentNugget Objects 12/31/2018 msen@ecs.syr.edu

Survey Objects 12/31/2018 msen@ecs.syr.edu

Performance Objects 12/31/2018 msen@ecs.syr.edu

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Supervisor Objects 12/31/2018 msen@ecs.syr.edu

System Administration Objects 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

XSL 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

Framework of frameworks 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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, http://www.uefa.com/ucl/ resource owner author property Alice name value email John Smith John@email.com 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu

Adapter Adapter Adapter NameSpace: LMS NameSpace:Science NameSpace:Government NameSpace: Science Adapter Adapter NameSpace: Entertainment Adapter 12/31/2018 msen@ecs.syr.edu

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 msen@ecs.syr.edu LMS 2

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu

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 msen@ecs.syr.edu