We propose a simple and efficient protection method for access control in co-authoring Systems. In this method we integrate the access control authentication into the key and lock distribution scheme to obtain an authenticated secure session key distribution system. This method has advantages on performance in Co-authoring systems, especially, while adding new files and users to the system.

This paper brings together two research issues in optical flow estimation: the selection of the smoothing parameter and the proper treatment of the correlated noise in the partial derivatives of the image intensity. In previous work, the authors have developed an optical flow estimation method which properly treats the errors-invariables problem cause by the correlated noise in the spatiotempor...

This paper describes an authoring tool, Visual Constructor, that is being developed to help users without technical knowledge to create and organize World Wide Web-based course contents. The following goals of Visual Constructor are highlighted: (1) it does not require any knowledge of evolving Web technology; (2) the user interface is easy to understand and operate; (3) it is a Web-based remot...

This document describes a MAPOS extension, Node Switch Protocol, for automatic node address assignment. MAPOS is a multiple access protocol for transmission of network-protocol datagrams, encapsulated in High-Level Data Link Control (HDLC) frames, over SONET/SDH. NSP automates the HDLC address configuration of each node. Using NSP, a node retrieves its HDLC address from the switch to which it i...

One promise that has always been made in the field of e-learning is the possibility to create and deliver learning material that is adaptable to individual learners. Realising this vision requires the possibility to reuse existing learning objects, combining them in new contexts. Reuse, in turn, can only be supported, if a flexible versioning scheme is in place that can easily handle multiple v...

This article presents the functional architecture and the interaction model of GENITOR, a generator of Intelligent Tutoring Systems (ITSsj. The major design issues that arise during the functional design and development of an ITS-generator concern the provision of mechanisms capable of supporting the description of the teaching subject domain and the specification of pedagogical features of the...

The Internet transport infrastructure is moving towards a model of high-speed routers interconnected by optical core networks. The architectural choices for the interaction between IP and optical network layers, specifically, the routing and signaling aspects, are maturing. At the same time, a consensus has emerged in the industry on utilizing IP-based protocols for the optical control plane. T...