Special Issue On 'ubiquitous E-learning Solutions Over Heterogeneous Networks'

摘要

The recent advent and proliferation of wireless networking solutions such as DVB/DVB-RCS, VSAT, DVB-S/S2, WiFi, WiMax, and UMTS/3G, to name but a few, has raised the expectations for delivering media rich e-learning content any time, any place. Towards meeting this challenge, bandwidth, reliability of content delivery, as well as economic feasibility are key factors that require fresh research on innovative end-to-end tele-education systems. Accordingly, this special issue targets precisely the area of ubiquitous e-learning solutions built over heterogeneous networks-their implementation, deployment and use. The issue kicks off with the paper by Salzmann, Gillet and Mullhaupt who present a new end-to-end adaptation scheme to provide the user with the best possible interacting experience, while considering imposed constraints in the ubiquity of the solution, the adaptability to the E2E infrastructure, and the respect of the Internet best practice. They consider three dimensions in their adaptation scheme-the level of interaction (how quickly a feedbackrnis provided to the user), the system dynamics rendering (how accurately in time the behavior of the remote system is perceived), and the amount of semantic content (how well the distant equipment state and conditions of operation can be perceived by the client). The feasibility of the proposed solution is then shown under the extreme networking constraints of a PDA accessing content remotely over a Bluetooth link.