Tayeb Lemlouma, December 2001.
(PDF)
E-Mail: Tayeb.Lemlouma@inrialpes.fr
We discuss here the role of services negotiation in the e-learning environment. Providing a complete solution in such contexts is very important and allows supporting the diversity of clients (or students) characteristics. Indeed, the e-learning is related to users capacities and preferences. For example a user, which can be a student that uses its PDA device, can be satisfied with the reception of only the abstract of a course instead of the whole content that could be heavy to use in respect of the user agent characteristics (hardware, software, etc.)
The negotiation task between the e-teacher and the e-student aims to deliver
a best content according to the client profile. This last can be declared
efficiently in an RDF [5] or a CC/PP structure [1]. The client can negotiate
then, with the environment to receive well adapted courses in respect to the
used user agent capabilities but also to the level and the nature of the
wanted e-learning by the student. For example, the negotiation process can
end to deliver abstracts and to skip (or reduce) images of biologic parts of
an original course, if the user is interesting more to the electronic parts
of the course.
It's important to note that the negotiation interactions are concerned by the use of final products of the e-learning environment and not by the cooperation between teachers during the authoring process. The negotiation task can be applied, on the fly, on final contents, eventually produced after cooperation tasks of the working in group. Thus, we can allow to a future device (a future e-student) to exploit the environment and to use understandable content according to its declared profile (figure 1). Authoring a negotiable content must be one of the major concern during the e-learning authoring step. Basic and required steps (such as the definition of content and courses profiles [2] ) can be easily achieved since the proposed e-learning environment uses opened models like XML and SMIL which facilitates ensuring device independence principle.
Since actual protocols, such as HTTP/1.0 [3] and TCN [4], are based on pure
versioning selection mechanisms and lack for performed negotiation strategy;
we propose -as perspective- the use of a proper negotiation layer as the one
introduced in [2]. The layer and the protocol can be adapted and integrated
to meet the e-learning context and environment since the proposed one still
remains opened and extensible.
[1] W3C Working Draft, Composite Capability/Preference Profiles(CC/PP):
Structure and Vocabularies, 15 March 2001.
[2] Tayeb Lemlouma, Nabil Layaïda, "The Negotiation of Multimedia Content
Services in Heterogeneous Environments", The 8th International Conference on
Multimedia Modeling, CWI, Amsterdam, November 5-7, 2001.
[3] Network Working Group, Hypertext Transfer Protocol - HTTP/1.0,
http://www.ics.uci.edu/pub/ietf/http/rfc1945.html, May 1996.
[4] K. Holtman TUE, A. Mutz, Transparent Content Negotiation in HTTP,
http://gewis.win.tue.nl/~koen/conneg/rfc2295.html. Network Working Group,
March 1998.
[5] Ora Lassila, Ralph Swick, Resource Description Framework (RDF) Model and
Syntax Specification, W3C Recommendation:
http://www.w3.org/TR/1999/REC-rdf-syntax.