CLAG 2004 – April/041 A Workflow-based Architecture for e- Learning in the Grid Luiz A. Pereira, Fábio A. Porto, Bruno Schulze, Rubens N. Melo

CLAG 2004 – April/042/21 Agenda Introduction/Motivation Description of the Environment Description of the Architectural Model Related and Future Works and Concluding Remarks

CLAG 2004 – April/043/21 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/044/21 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/045/21 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 costs reduction and quality improvement.

CLAG 2004 – April/046/21 Introduction/Motivation Proposed Solution(cont.):  (Cost) effective content delivery mechanisms  Web based environment  Massive computing power and/or data storage  Grid

CLAG 2004 – April/047/21 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/048/21 Introduction/Motivation TEAM (the architectural model): TEAM A TEAM (the environment): TEAM E, instantiated to e-learning.

CLAG 2004 – April/049/21 Description of TEAM E 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/0410/21 Description of TEAM E 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/0411/21 Description of TEAM E The environment is logically divided in two scopes, external and internal, according to user roles.

CLAG 2004 – April/0412/21 Description of TEAM E 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/0413/21 Description of TEAM E 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/0414/21 Description of TEAM E The distributed e-learning environment scopes Peer 1 … Peer 2 Peer 4 Peer 3 Internal Users External Users Internal Users

CLAG 2004 – April/0415/21 Description of TEAM E 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/0416/21 Description of TEAM A Architecture based on mediator(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/0417/21 Site 1 Site 2 Site 3 Site 4 P1 P2P3 P4P5 P6 Grid 1 Grid 2 Description of TEAM A TEAM A conceptual view TEAM Connection Grid Connection

CLAG 2004 – April/0418/21 Description of TEAM A Each peer in TEAM A 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/0419/21 Description of TEAM A TEAM 3-tier architecture 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. Application Browser User associated to site i Web services for data sources access Control Data Metadata JSP Web services Workflow enactment service Grid

CLAG 2004 – April/0420/21 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/0421/21 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