The learning computer is conceptualised as the front-end of a networked e-learn ing system for extramura l study. The main components of this network, and their h i g h level req u i rements, are discussed in Chapter 4 (4. 4 . 2 ) . Ease of mainten ance and reusability require a clear separation of functionality between these network elements
I M M EDIATE is a prototype system developed to test and evaluate the concept of the learning computer. lt therefore needs to implement only those elements that are necessary to ach ieve th is.
While the student interface is central to the learning computer concept, this project is much more than an inte rface evaluation exercise . lt is also about proving the feasibility of a mechanism for the authoring and delivery of learn ing material in support of a colla borative learning environ ment, that is accessible and usable by extramural students studying alone, utilising strategies of specialisation, localisation and adapta bility. This means that to implement I MME D IA TE for the pu rposes of eva luating the hypothesis, three sepa rate prototypes need to be built and then integ rated i nto a working system . They are a Learning Shell, a C o u rse Authoring and Management Application and a Communications Manager.
The Authoring application is linked to the Com munications Manager a nd the Course Repository via a Local Area Network (LAN ).
Earlier in this chapter (5 . 4 ) , the rich variety of communication media that ca n be supported within this approach was highlighted , includ ing standard telephone, wireless, digital satellite and postal technolog ies . The essentia l requirements are the provision of a bi-directional narrowband Internet connection for communications and a uni d i rectional broadband media for downloading learning resou rces from the cou rse repository to the learning com puter. Va riations between telephone, wireless and satellite broadband delivery are resolved at the level of the computer hardwa re and operating system, and appea r to the learning com puter as an Internet connection.
Therefore the two main categories of commun ication media that need to be evaluated through prototyping are the Internet and portable sto rage med ia.
The Learn ing Shell is l inked to the Communication s Manager via the I nternet using a secure FTP connection and through portable storage media such as CD-ROM . This provides one bi-directional communications med i u m (i.e. the tra nsfer of message files over the Internet using FTP) and two unidirectional download media ( i . e . downloading resource files using FTP via a ny lnternet-enabled channel or by mail using portable data storage). Resou rces external to the Repository are accessed via the Internet.
Chapter 5: Towards a specification 1 1 0
The essentia l components of IMM E D IATE and its configuration a re depicted in Figure
5 . 1 0 . Th is is a simplified network a rch itectu re specification, compared to that in Figure
5.4, but it is sufficient to evaluate the learning computer concept.
On-campus
Authoring, Tutoring System
External
Off -campus Resources
(w w w) � Internal links External links LAN Communications Manager Internet
\� ...
Repository (database, files) Learning Shell (Student user)F i g u re 5.1 0: IMME DIATE network components and configu ration.
5.8 Summary - Prototype Focus
This chapter has presented a partial specification for a special ised computer for learning, and its supporting network services . This provides the framework for implementing a prototype system called I M M E D IATE . Key aspects to I M M E D IATE's design include :
• A client/server network architecture in which the student client is implemented as a specia lised Learning Shell over the Windows o perating syste m . The university server provides data updates to the student clients over the network, or by a lternative med i a , and enables two-way communications between students and betwee n students and teaching staff. Learning functionality is distributed to the student clients .
• The Learning Shell is assembled from reusable RAD "drag a nd d rop" components
with settable properties. Different study modes (learning dimensions) a re defined by particul a r combinations of components, to which appropriate learning resources are bou n d . Learning components a re defined from the user's perspective by the
Chapter 5 : Towards a specification 1 1 1
"what" rather tha n the "how" e.g. "lectu res" not "media player", "study guide" not "web browser".
• The integrity of the Shell is ma intained by a system layer, containing a Controller
object and a reference model , which maps Shell operations to the operating syste m . The reference model is centred upon a System Tree, defined by the structu re of the study guide, a s the basis for a di rectory system, a student model and learning support. The System Tree defines a hierarch ical cou rse structure by course title, section, and topic. Each learning component has a d i rectory system mapped to it. Changing the study mode does not change the student's position in the System Tree . Changing the position in the System Tree does not change the study mode.
• The integ ration of commun ication , collaboration and extram ural learning su pport into a single distributed database system organ ised on a mobile computing model. This is mapped to the System Tree to provide the structu re for a coa rse-gra ined
knowledge base which can be q ueried along several dimensions.
The n ext step in the methodology is to use prototyping to further explore and refine the key e lements of I M M E D IATE 'S design . These elements can then be integ rated into a working prototype, including additional applications to test the networking and autho ring support. This prototyping work is the subject of the next chapter.
Chapter 6: Prototyping 1 1 3