Presentation is loading. Please wait.

Presentation is loading. Please wait.

LON-CAPA 1 Management Issues in Distributed Learning Content Management Systems Gerd Kortemeyer Michigan State University.

Similar presentations


Presentation on theme: "LON-CAPA 1 Management Issues in Distributed Learning Content Management Systems Gerd Kortemeyer Michigan State University."— Presentation transcript:

1 LON-CAPA 1 Management Issues in Distributed Learning Content Management Systems Gerd Kortemeyer Michigan State University

2 LON-CAPA 2 Overview Example System: LON-CAPA Issues: Content Exchange Content Assembly Content Catalogization Content Rights and Licenses Commercial Content Protected Content Content Integrity Content Quality Control Scalability Content Replication Load Balancing Distributed Authorizations Distributed Coding Maintenance and Security

3 LON-CAPA 3 Example System For illustration, examples from the LearningOnline Network with CAPA will be used Cross-Institutional Learning Content Management and Assessment System Today, I will only focus on Content Management Implemented components, from bottom up (Just Do It): a cross-institutional distributed content repository a tool to seamlessly assemble this content a course management system to readily deploy this content

4 LON-CAPA 4 Example System Initial development started in 1992 at Michigan State University Distributed Content Management component since 2000 Model System for National Science Foundation Information Technology Research Project Investigation of a model for online resource creation and sharing in educational settings Faculty are the authors and users of the content material (sort of grassroots).

5 LON-CAPA 5 Example System Currently used at 3 middle schools, 16 high schools, 2 community colleges, and 16 universities Approx. 23k students/semester

6 LON-CAPA 6 Example System 20,900 content pages 18,600 homework and exam problems 12,500 images 2,100 content assemblies 1,100 simulations and animations 500 movies Publisher libraries, back of the chapter problems

7 LON-CAPA 7 Example System

8 LON-CAPA 8 Content Exchange Providing high quality learning content in an online environment is time and cost intensive Typical scenario today: Online material is developed by only one instructor Online material is used by only one instructor Online material is used in only one course No assessment of learning effectiveness In-effective use of time and resources

9 LON-CAPA 9 Content Exchange Much better scenario: Online material is developed and reviewed by more than one instructor Online material is shared among instructors Online material gets used across many courses and disciplines Continual assessment of learning effectiveness

10 LON-CAPA 10 Content Exchange Issue: Content Compatibility Content developed at institution A needs to run at institution B Three approaches Standardize content Standardize APIs for content handlers Standardize on one platform

11 LON-CAPA 11 Content Exchange Approach 1: Attempt to define how the content is coded: IMS, SCORM, QTI, etc Advantage: Portability between vendors Problems: content has to run in lowest common denominator system restrictive on content no standard is perfect: long loop to implement innovations no guarantee that this will really work all the time

12 LON-CAPA 12 Content Exchange Approach 2: Attempt to define how content handlers interact (APIs; content can come with its own handler): OKI Advantage: only mildly restrictive on content Problem: restrictive on overall system functionality no standard is perfect: long loop to implement innovations where is it?

13 LON-CAPA 13 Content Exchange Approach 3: Attempt to have the same platform everywhere: LON-CAPA (content-level), BlackBoard Building Blocks (API- level), etc Advantages: content that runs on machine A is guaranteed to run on machine B faster turn-around on innovations Problem: potentially costly solution for commercial products creating dependencies, all eggs in one basket

14 LON-CAPA 14 Content Assembly Writes module on statistical averages Writes module on statistical errors Includes the two into her unit on survey analysis Uses that unit in his course

15 LON-CAPA 15 Content Assembly Made possible (in LON-CAPA) through: Reuse: Separation of content for navigation/interface and presentations Self-contained content can be reused on low level of granularity Content Assemblies themselves can be reused Navigation is provided by the system based on the assembly data, not by the content On-the-fly rendering: XML structures for multi-lingual presentation, server-side style files

16 LON-CAPA 16 Content Assembly Virtual cross- institutional file system The aisles of your supermarket Your shopping cart: The Resource Assembly Tool

17 LON-CAPA 17 Content Assembly

18 LON-CAPA 18 Content Rights and Licenses Very important: distinguish between copyright and different rights of use (licenses) Who has the right to use a resource? Who has the right to deterimine that somebody else may use it? Who has the right to modify a resource?

19 LON-CAPA 19 Content Rights and Licenses LON-CAPA: Authors keep copyright LON-CAPA: Authors (currently) grant right of use private only for own institution (after other instructor selects it) network-wide (after other instructor selects it) public customized: for certain institutions, courses,... access keys

20 LON-CAPA 20 Content Rights and Licenses Setting custom access rights Allowing access by key only (publisher content)

21 LON-CAPA 21 Content Catalogization Sharable content is useless if you cannot find it Metadata (data about data) needed What standard? Dublin Core? IMS? Too much data: nobody will fill it out Too restrictive data: cannot be used to store additional data, for example geo-coordinates Who does the cataloging? Librarian: not scalable Author: potentially inconsistent, unreliable

22 LON-CAPA 22 Content Catalogization LON-CAPA Static metadata: Dublin Core plus additional fields cross-walk to some of IMS Done by author with system assistance (keyword suggestions, hierarchical default entries) Dynamic metadata: use assembly data for recommender system:

23 LON-CAPA 23 Content Integrity What if you use somebody elses resource in your course … … and it goes away? … it changes in an undesirable way? LON-CAPA: once-published resource cannot be deleted Persistent system-wide URLs versioning: can choose to fix course to current version of a resource, can check on changed resources and selectively adopt new versions resource users cannot edit resource unless explicitly given co-author rights to the original source

24 LON-CAPA 24 Content Quality Control Could implement peer-review (example: MERLOT) Can inhibit growth of resource pool, not easily scalable LON-CAPA: keep dynamic metadata regarding Number of courses using the resource Number of other resources importing it Number of students who accessed it Problem-Content: Number of students who worked on it Degree of difficulty Subjective evaluations Usage data

25 LON-CAPA 25 Scalability Success can be a problem: Successful resources: server load Number of users: processing load Success must not be a problem: scalability

26 LON-CAPA 26 Scalability Network of connected servers Any server in the network can serve any resource in the system Content replication in background Network-wide persistent URL paths

27 LON-CAPA 27 Scalability North Dakota State University server serving resource from Michigan State University First time the resource is accessed, it is copied in the background (replicated) closer to user MSU not stuck with serving the resource will continue to work if connection to MSU down Leaves behind subscription on MSU server When resource updated at MSU, NDSU copy is either updated or deleted, depending on usage pattern

28 LON-CAPA 28 Scalability Network of connected servers Any server in the network can serve sessions for any user Servers can offload sessions to each other cross-institutionally Load-balancing

29 LON-CAPA 29 Scalability x5

30 LON-CAPA 30 Distributed Authorizations One user can have roles across the network Each role comes with a set of privileges within a certain realm (course, domain, whole network)

31 LON-CAPA 31 Distributed Coding Open-source free software GNU General Public License No license fees Can be modified, extended, improved, adapted... Runs on Linux, no license fees for operating system Developed by educators for educators Central CVS code repository Releases defined centrally

32 LON-CAPA 32 Distributed Coding Code contributions by Florida State University Ohio University Simon Fraser University Vancouver Hebrew University Jerusalem UNICAMP São Paulo Nagoya University

33 LON-CAPA 33 Distributed Coding

34 LON-CAPA 34 Maintenance and Security Danger in distributed network: trust relationships between machines: one rogue machine can leak problem source codes or be abused to grant higher authorizations to users Monitoring processes Local system administrators need to keep machines up-to-date Remote maintenance options Frequent release schedule and quick updates Mechanisms to quickly take machine offline

35 LON-CAPA 35 Funding Michigan State University Mellon Foundation Sloan Foundation National Science Foundation Ohio University, Florida State University, Ohio University, Nagoya University, UNICAMP, Simon Fraser University, Hebrew University of Jerusalem People who drive too fast


Download ppt "LON-CAPA 1 Management Issues in Distributed Learning Content Management Systems Gerd Kortemeyer Michigan State University."

Similar presentations


Ads by Google