Mohamed Bourimi

Supporting flexible collaborative distance learning in the CURE platform

At the German Distance Learning University, five collaborative distance learning scenarios have been recently identified by students and teachers as an important future form of collaborative learning in the universitys virtual learning space. An analysis of these scenarios showed a great variance between them and a need to support runtime tailoring of the respective learning environments. Since no existing learning platform addresses all the needs, the CURE collaborative learning platform was developed to support the implementation of such a variety of tailorable learning environments. CURE is based on a room concept and supports the implementation and runtime tailoring of collaborative distance learning environments for our scenarios. Initial experience indicates its applicability.

End-user controlled group formation and access rights management in a shared workspace system

Group formation and access rights management become crucial issues when shared workspaces are used to support flexible, emerging group work. End-Users should be able to form groups and adapt access rights for changing groups and workspaces. Current shared workspace systems do not support this sufficiently. Our approach combines a room metaphor-based shared workspace with the key-metaphor for facilitating both, end-user controlled flexible group formation and access rights management. An evaluation of this approach during four month of use has indicated that end-users can form groups and manage the access rights of their shared spaces.

Two-level tailoring support for CSCL

At the FernUniversitat Hagen, we develop a collaborative learning platform, which supports a variety of collaborative distance learning scenarios through the provision of groups, tailorable adjacent rooms associated to groups, and networked content pages and group communication media contained within rooms. Learners can add and manipulate content within rooms and may add/remove rooms. Experts (teachers), in addition, can define and manipulate templates for the content allowed on pages in rooms, and may also add or change the group tools available in rooms. This supports tailoring of learning environments at two levels: at the structural and functional level and at the content level. The current system is presented, and an example of use is discussed.

Towards Transparent Anonymity for User-controlled Servers Supporting Collaborative Scenarios

The increasing tendency of using user-controlled servers for supporting different scenarios from leisure and professional life raises new security challenges. Especially when those servers are used to support collaborative scenarios (e.g., communication and sharing with others), the requirement for anonymity at the network level should be supported in an efficient way. In this paper we present a specific communication scenario that could lead to link ability even though anonymous networks are used. The requirements gathering is based on realistic requirements from the EU FP7 di.me project requiring to empower lay end-users to collaborate with their contacts. Thereby anonymity at the network level also needs to be considered in order to disguise the physical location of the users and also of their server(s). We present an approach satisfying these anonymity requirements by means of a Tor based software component in order to overcome such privacy problems. First results are presented and the portability of the suggested solution for similar settings as well as future work directions are discussed.

Leveraging visual tailoring and synchronous awareness in web-based collaborative systems

Web-based cooperative systems hardly use approved user interface concepts for the design of interactive systems and thereby aggravate the interaction of the users with the system and also with each other. In this article, we describe how the flexibility and usability of such systems can particularly be improved by supporting direct manipulation techniques for navigation as well as tailoring. The new functionality for tailoring and navigation is complemented by new forms of visualizing synchronous awareness information in web-based systems. We show this exemplarily by retrofitting the web-based collaborative system CURE. However, the necessary concepts can easily be transferred to other web-based systems.

Context-Aware, Trust-Based Access Control for the di.me Userware

Trust calculation to inform privacy recommendations based on context information involvement (e.g. location information, nearby people) is an increasing need in pervasive environments. In this paper we present a multidimensional trust metric designed for access control decisions in scenarios of the EU funded digital.me project. Thereby each involved context information could represent a separate trust dimension. In the focus is the correctness of the suggested trust metric towards meaningful privacy recommendations and improvement of access control decisions for our scenarios. The suggested metric could help to avoid manipulations and attacks based on fundamental requirements for situational trust. Our proposed trust calculation considers a presence history of persons at locations, to increase the accuracy of our base trust value. We present our approach after explaining the fundamental requirements, the underlying ontology framework and architecture.

A Requirements-Driven Approach Towards Decentralized Social Networks

A new generation of distributed social networks is promising to give back users full control over their personal information as shared in private and business life. However, there are many aspects to this control, such as information ownership, access to third parties and limited persistence. This paper compares various existing solutions against an analytically elaborated list of user requirements. Based on this comparison, we also present a comprehensive and integrated approach to overcome the major issues outlined for the existing solutions, including first experiences of applying the reference implementation.

TOWARDS AN ENHANCED ADAPTABILITY AND USABILITY OF WEB-BASED COLLABORATIVE SYSTEMS

Web-based collaborative systems support a variety of complex scenarios. Not only the interaction among one user and a computer has to be modeled but also the interaction among the collaborating users as well. As a result, the user interfaces of many web-based collaborative systems are quite complex, but hardly use approved user interface concepts for the design of interactive systems. Thereby, web-based collaborative systems aggravate the interaction of the users with the system and also with each other. In this article, we describe how the adaptability and usability of such systems can particularly be improved by supporting direct manipulation techniques for navigation as well as tailoring. The new functionality for tailoring and navigation is complemented by new forms of visualizing synchronous awareness information and supporting communication in web-based systems. We show this exemplarily by retrofitting the web-based collaborative system CURE while highlighting the concepts that can be easily transfe...

Towards secure and at-runtime tailorable customer-driven public cloud deployment

Cloud computing as a facility for outsourcing IT related tasks is a growing trend. Customer-driven application deployment in public clouds has to be secure and flexible by means of easing security configuration as well as by avoiding the vendor lock-in problem. In this paper we present an approach intending to meet these needs by (1) easing security configuration(s), (2) automating the consideration of security best practices and adding/enabling anonymity components at-runtime, and (3) by using Open Virtualization Format (OVF) in order to overcome the vendor lock-in problem. The requirements gathering is based on the needs of three projects from different business domains, the EU FP7 digital.me project, the multidisciplinary iFishWatcher/iAngle combined project and the joint german-french research and development project ReSCUe IT. All projects require empowering lay as well as experienced customers to (re-)deploy their own applications and migrate them easily by considering security thereby. Supporting tailorability of the deployed environment by adding anonymity components at-runtime without downtimes is a specific requirement in these projects. We present first results and discuss experiences and future work directions.

Privacy and Security in Multi-modal User Interface Modeling for Social Media

This paper addresses privacy and security issues regarding the modeling of multi-modal user interfaces for social media applications. The proposed approach describes how privacy and security concerns are modeled from the user interface perspective, and how this model is related to a four layer conceptual framework for developing multi-modal and multi platform user interfaces. The approach also explains how to adapt these models to the development of social media applications. Finally, we use this proposal to model the Social TV case of study as an example of a social media application to show its feasibility.