A Workflow-based Architecture for e-Learning in the Grid

1. A Workflow-based Architecture for e-Learning in the Grid Luiz A. Pereira, Fábio A. Porto, Bruno Schulze,Rubens N. Melo {lpereira,rubens}@inf.puc-rio.br, {fporto,schulze}@lncc.br CLAG 2004 – April/04

2. Agenda • Introduction/Motivation • Description of the Environment • Description of the Architectural Model • Related and Future Works and Concluding Remarks CLAG 2004 – April/04

3. Introduction/Motivation • Motivation: • PGL (Partnership In Global Learning) Project (PUC/UF) • Many partners providing learning content in a global scale: data distribution, technological heterogeneity, easy and cost effective content access. • e-Learning scenarios requiring computational-intensive learning objects for simulation purposes (LNCC) • Fluid mechanics course containing the simulation of a fluid path, which requires the computation of virtual particles trajectories (applied to hemodynamics) CLAG 2004 – April/04

4. Introduction/Motivation • Requisites: • Effective e-learning environments should promote high cooperation. Benefits: • in the cognitive domain, improving learning capacity and academic performance. • in social and affective ones – improving group and individual self-confidence. • It is important to consider new methods to reduce learning content development costs. • It is also important to consider (cost) effective content delivery mechanisms. • Many cases requiring massive computing power and/or data storage usually not available in a single workstation. CLAG 2004 – April/04

5. Introduction/Motivation • Proposed Solution: • Cooperation  WfMS, providing: • Executor-task assignments • Effective interaction coordination • Execution duration control and synchronization • Coordination of the execution of tasks involving massive computation and/or data processing. • Content development cost reduction  use of modular and reusable learning modules (LOs): • To facilitate deployment and execution assignment • Reusability and standardization contributing to content development costsreduction and quality improvement. CLAG 2004 – April/04

6. Introduction/Motivation • Proposed Solution(cont.): • (Cost) effective content delivery mechanisms  Web based environment • Massive computing power and/or data storage  Grid CLAG 2004 – April/04

7. Introduction/Motivation • TEAM is both • An architectural model: Teamwork-support Environment Architectural Model • Operating environments based on the architectural model:Teamwork Applications Manager CLAG 2004 – April/04

8. Introduction/Motivation • TEAM (the architectural model): • TEAMA • TEAM (the environment): • TEAME, instantiated to e-learning. CLAG 2004 – April/04

9. Description of TEAME • Students and teachers would execute instructional steps cooperatively guided by a WfMS • WfMS deals transparently with distribution, autonomy and technological heterogeneity of the content repositories that are located in the partners’ sites • Content is LO-oriented and is described using the IEEE-LOM standard. CLAG 2004 – April/04

10. Description of TEAME • The processing unit of the environment is called a peer, working as a gateway to environment • Provides user’s authentication, • User-environment interaction control, • Execution context management. • Each user is associated to a peer • A site is a logical collection of peers sharing a common learning purpose • Users have transparent access to resources within sites in which his home peer is included CLAG 2004 – April/04

11. Description of TEAME • The environment is logically divided in two scopes, external and internal, according to user roles. CLAG 2004 – April/04

12. Description of TEAME • The external scope: • Provides an environment for students accessing courses they are registered to attend. • External users “see” the (distributed) environment as just one piece • The workflow enactment services provide this transparent vision to external users, routing, retrieving and allocating resources to/from proper peers CLAG 2004 – April/04

13. Description of TEAME • The internal scope: • Refers to the working context of the environment’s the internal users: • Technical support staff, • Application developers, • Database administrators and • Learning content developers CLAG 2004 – April/04

14. External Users Internal Users Peer 1 … Peer 2 Peer 4 Peer 3 Internal Users The distributed e-learning environment scopes Description of TEAME CLAG 2004 – April/04

15. Description of TEAME • What about content? • It is LO-oriented • Developed in “reusable modules” from scratch and/or • Developed by aggregating LOs developed by other partners • Lightweight or • Heavyweight, requiring Grid resources CLAG 2004 – April/04

16. Description of TEAMA • Architecture based onmediator(s) and wrappers • Peers are functionally identical but some of them run on top of a grid (operating) system to access resources provided by grid environment(s). • Grid resources management to be done transparently from the user perspective CLAG 2004 – April/04

17. P1 P2 P3 Site 2 Site 1 P6 P5 P4 Site 4 Site 3 TEAM Connection Grid Connection Grid 2 Grid 1 Description of TEAMA TEAMA conceptual view CLAG 2004 – April/04

18. Description of TEAMA • Each peer in TEAMA is a stack of three layers (a 3-tier architectural model) • User Interface, • Workflows services (business processes/rules) • Other services (data persistence, resource scheduling, …) . CLAG 2004 – April/04

19. User associated to site i Application Browser JSP Web services Workflow enactment service Web services for data sources access Grid Metadata Data Control Description of TEAMA User interface with the environment: a web browser or a .NET application. The functional core of the architecture: The workflow enactment service managing a convenient portion of the whole workflow instance. Service layer provides data persistence and grid access for heavyweight tasks. TEAM 3-tier architecture CLAG 2004 – April/04

20. Related and Future Works and Concluding Remarks • At LNCC we are developing a grid infrastructure to be used transparently from several kinds of applications. • One of these types of applications is an e-Learning Management System capable of sharing distributed e-learning modular content and controlling student-student and student-teacher collaboration. CLAG 2004 – April/04

21. Related and Future Works and Concluding Remarks • TEAM extension towards its integration with grid infrastructure is at its initial phase. • We need to integrate user authentication between TEAM and the grid • We need to develop a more refined authorization policy that will include information on user rights to access a LO • We need to extend our current LO storage and query services • We need to refine how our search for LOs will be implemented • We need to improve workflow specification to work on a non-structured scenario CLAG 2004 – April/04