Connecting Virtual Spaces: Shadow Objects as Key Elements for Weaving the Cooperative Space

Cooperative knowledge areas are a well-proved approach to support process of cooperative work and ELearning. The Paderborn Open-Source system sTeam establishes cooperative knowledge spaces so far as a single server implementation. This paper presents our architecture of distributed cooperative knowledge areas. The main conceptual idea of the sTeam system is a combination of a document management system and a MUD. The goal of a distributed architecture of cooperative knowledge spaces is the ability to create one world of connected virtual knowledge spaces over various servers. Something, which is especially important, when thinking of new scenarios of integrating peer-to-peer clients into a multi-server architecture. Distributed knowledge spaces also have to cover concepts for a multi-server group and user management, which allow to move users transparently from one server to another. Materials should be structured independently of their location on a server. The following paper first discusses the idea of structuring a virtual world into zones or areas, which is also found in multi-user virtual environments. After that our architecture of distributed cooperative knowledge areas is presented. In the field of user management two different approaches of a peer-to-peer and master-server group and user-management are possible and discussed in detail. Our trial implementation will be a fusion of both concepts and prototypes.