The ELearning Lifecycle and its Services: The Web Services Approach

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The E-Learning Lifecycle and its Services The
Web Services Approach

• By Angad Grewal, Shri Rai,
• Rob Phillips and Chun Che Fung

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Overview

• The e-learning industry is moving forward. One
  of the pressing issues at present is the strife
  for common accepted standards so as to encourage
  interoperability and reusability.
• In our Interoperable E-Learning Infrastructure
  Lifecycle using Web Services, all the e-Learning
  components and learning objects would be well
  established, effectively discovered and loosely
  connected.
• As we move towards a world of loosely coupled
  applications capable of exchanging data freely
  and communicating with a broad range of devices.
• In a diverse environment where content,
  delivery, management and analysis tools are being
  produced by a number of vendors, interchanging
  data and developing a common interface between
  various components calls for development of
  common standards.

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• Interoperability emphasizes the need to have a
  standard communication methodology (protocols)
  between various components of e-learning systems.
  
• Thus the use of open standards would allow
  interoperability and reusability at different
  stages of an e-learning solution.
• One significant way of achieving
  interoperability is through agreed standards and
  specifications. These may be international or
  local. There will be some local needs such as
  curriculum requirements. The specifications and
  standards may be generic such as HTML or they may
  be for e-learning such as LOM.

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E-Learning Lifecycle
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ActorsThe list of actors who play an important
role in the lifecycle of a Digital Resource and
are listed below.

• 2.3.1 Actors
• The list of actors which were identified play an
  important role in the lifecycle of a Digital
  Resource and are listed below.
• .
• a) The Creator uses a Creation Tool to create a
  Digital Resource. An example of such a resource
  is digital asset.
• b) The Author uses an Authoring tool to put
  existing content (such as text and graphics) into
  a logical arrangement thus creating a Compound
  Digital Asset of a Learning Object. Examples can
  include Macromedia Flash, Macromedia Director,
  Flash and Dreamweaver.
• c) The Discoverer uses a Federated Search Engine
  to discover existing digital content. Search
  engine examples are Webfeat, Metalib and Fretwell
  Downing.
• d) The Librarian uses the Metadata Creation Tool
  to describe the newly created digital resource.
• e) The Organizer uses Sequencing tools to convert
  simple learning objects into complex learning
  objects. These complex learning objects can be
  packaged as either IMS content packages or SCORM
  Shareable Courseware Objects . These packages
  contain a manifest, which describes the content
  of the package. Such packages enable Learning
  Management System to connect directly to a SCORM
  manifest .
• f) The Arranger uses a Learning Activity
  Management System to structure digital resources
  (e.g. complex learning object) into Learning
  Activities .
• g) The Learning Manager negotiates with the
  Broker concerning the terms and conditions for
  using the desired digital resource.
• h) The Digital Rights Management can further be
  divided into 3 actors
• 1 The Intellectual Property (IP) Controller is
  the one who creates IP Rights for a Digital
  Resource. The IP rights for any given Digital
  Resource is also checked.
• 2 The Broker negotiates license deals (e.g.
  permissions for modifying learning resources).
  The Broker demands payment from the client or
  customer. On receipt of such payments (e.g.
  royalty payments), the broker allows access to
  the customer.
• 3 The Digital Rights Manager manages license
  usage and tracks license usage.

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E-Learning lifecycle In detail
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Content Creation Authoring
By Dr Rob Phillips Murdoch University
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Components of E-learning Lifecycle

• Digital assets the electronic resource like a
  image, chart, formula.
• Content objects Digital assets contextualised,
  e.g. adding text to tell the learner what to do
  with the content like an image with supporting
  text or labels
• Learning objects consist of content object
  directed towards a particular learning outcome,
  with assessment to measure performance.
• Below use case for each Digital Resource is
  created by examining how each actor uses tools to
  create/manage the Digital Resources.

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Digital Asset

• A Digital Asset is defined as any piece of
  content that is created using technology.
• It could be any remote electronic resource like
  an image, chart, or even a formula.
• A digital asset can be web-based or CD/DVD-based,
  depending on file content and consumer needs.

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Compound Digital Asset

• Compound Digital Assets can be best described as
  digital assets with contextualised information
  (e.g. addition of metadata).
• Examples for these are when some text is added to
  a JPEG image or a description explaining a
  mathematical formula.

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Arnold
The Context and the digital asset
ASSET
Contextualisation of the asset
tell the learner what to do with the
content

• Consider a picture of the Arnold, which is
  readily available on the web. The definition
  above says that this picture is not, in itself, a
  learning object.
• A range of learning objectives might be
  facilitated by appropriately contextualizing this
  particular image
• We refer to the raw electronic source data of
  the picture as a digital asset and to any
  particular contextualization of it as a content
  object.

Content Object
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Learning Object

• We have defined a Learning Object as the
  aggregation of Digital Asset, Compound Digital
  Asset and Metadata with a particular learning
  purpose.
• It is made up of two components - the object
  content and its metadata
• Example they can take the form of a
  classroom-based electronic forum, or even a movie
  clip (with some sort of educational value).

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Complex Learning Objects

• Complex Learning Objects are packages consisting
  of structured assemblies of zero or more Digital
  Assets, zero or more Compound Digital Assets and
  one or more Learning Objects.
• These packages can be in the form of well know
  packaging formats like IMS or SCORM Shareable
  Courseware Objects .

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SOA

• Advantages of SOA
• Existing services can more easily be reused
• Apps can expose their services in a standard way
• Applications can be exposed more easily to
  diverse clientsWindows clients, ASP.NET/JSP, etc.

SOA
Application II
Application I
Common services
Application Platform Suite

• Application neutral services
• Maximize Reusability
• Self describing and self-contained
• Accessible from a variety of platforms

Java Virtual Machine
Operating System
Hardware
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What is a Web Service?

• A Web Service could be simply a service
  available via the Web
• This digital learning resource/service can be
  implemented as Java application, C application,
  Javascript code, etc.
• Usually, web service means a resource that can
  be accessed programmatically.
• In this case they could be a services to Locate
  and access remote learning object

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Web Services

• SOAP
• Simple Object Access Protocol
• XML message protocol for web services
• WSDL
• Web Services Description Language
• Allows programs to access descriptions of digital
  learning services
• UDDI
• Universal Description, Discovery and Integration
• Stores WSDL and other information about the web
  services (which in this case could be a remote
  Learning service)

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Web Services Standards
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This is how Web Services work with e-learning
Providers
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Service Requestor
publish
Register Web Service(at development time)
UDDI Registry
WSDL Document
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Web Services and e-Learning Description Step wise

• When the learning services go live they are
  registered in a service registry (UDDI), with a
  description of the learning resource that
  includes what it can do? and how to access it?
• These descriptions are written in XML.
• The Service Requester (client) uses the
  description and the other services in the
  registry to determine how to invoke the service
  and what response to expect in return.
• Thus this description is specified in a standard
  way by using WSDL.
• WSDL document contains sections that describe
• What that particular service (Learning Resource)
  can do?
• The operations it can perform?
• The protocols used to access that service
  (Learning Resource)?
• Where and How to access the service?
• Once the desired service has been discovered and
  its WSDL description used to determine its
  capabilities, like where the service resides and
  how to access it, the next step is to access or
  invoke the service.
• Thats where SOAP comes in, it is written in XML
• It defines a specification for how XLM massages
  can be passed over a network.
• Using SOAP as the standard protocol for
  accessing learning resources (services) does not
  tie the user to any particular transport method.
  It can be used over HTTP,SMTP, FTP and etc.

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Search Services
Content Provider Y
Content Provider Z
Content Provider X
UDDI Registry

• Content Discovery Service
• Look up Service
• The Broker or Digital Rights Manager can discover
  the desired learning content by sending a SOAP
  Query to the UDDI Registry.
• The information received from the UDDI Registry
  is only partial, though the URI of the WSDL
  document describing the Web Services is returned.
  This will be the URI of the Web Service followed
  by ?WSDL Examplehttp//myserver/service/learningc
  ontent?WSDL
• The Broker or Digital Rights Manager can get the
  desired learning content by sending the a request
  based on the URI retrieved from the UDDI
  Registry. This is returned over a transport
  protocol like HTTP.

Federated Search Engine A
Is Managed by the Broker or Digital rights
Manager
Federated Search Engine B
Learning Content Management System A
Learning Content Management System B

• Several services are registered in the UDDI
  registry
• These web services have been described as a WSDL
  document the URI or which can be found while
  accessing the UDDI
• These services could be deployed at and remote
  server
• (ex Tomcat web server using the axis SOAP
  engine)
• Thus the LMS 1 and LMS 2 can use these services
  to get access to remote learning objects.
  Irrespective of the language they have been
  written in.
• With the help of these services LMS or LCMS
  created by different vendors can re-use remote
  learning objects

Content Discovery Service Stored and deployed in
a remote Web Server
Learning management System B
Learning management System A
Look up Service Stored and deployed in a remote
Web Server
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Sequence Diagram of the Creation Stage
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Sequence Diagram of the Authoring Stage
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Conclusion

• The objective behind using web services as a
  middleware technology is to provide
  interoperability in the e-learning framework,
  right from the creation of a digital learning
  objects to a fully packaged courseware being
  delivered to a learner.
• In this paper, we have tried to identify and
  explain the steps involved in the creation of a
  raw digital asset and how it is transformed into
  a complex learning Object. This identification of
  steps or stages has lead to the creation of
  common services (which are also based on web
  services).
• These services (with real time web services
  technology) would provide a common interface
  between various components leading to platform
  independence and interoperability between
  learning systems.

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Thank you Any QUESTIONS Please?