The design and the security concept of a collaborative whiteboard

This paper presents the design and the security concept of the digital lect ure board, an enhanced whiteboard tailored to the specific needs of collabo rative types of work, for instance, in computer-based distance education. T he development of the digital lecture board emerged from our experiences wi th synchronous, computer-based distance education in the TeleTeaching proje cts of the University of Mannheim. For almost four years we have been using video conferencing tools for transmitting lectures and seminars. These too ls prove to be far from optimal for this purpose since they are not powerfu l enough to support team work, not flexible enough for the use of media, an d somewhat difficult to handle for non-experts. Security issues such as aut hentication, secure key exchange, and fast symmetric encryption are almost completely neglected, even though security is extremely important to allow for confidential, private sessions, and billing. We discuss shortcomings of existing video conferencing tools and describe features we had in mind whi le designing the digital lecture board. We then present our security concep t that is a user-oriented approach that takes into account the specific sec urity requirements of different user soups. We also cover implementation is sues of the current prototype. (C) 2000 Elsevier Science B.V. All rights re served.