A Model for Collaborative Services in Distributed Learning Environments

Synchronous collaborative work environments, which are mainly based on video-conferencing systems, suffer a lack of human communication channels and social awareness because mostly only audio, video, and joint editing of documents are supported. Collaborative services such as floor control, session control, and telepointers provide additional communication mechanisms to support persons co-working through computers. We propose a collaborative services model (CSM) for distributed learning environments. Our object-oriented approach includes floor and session control mechanisms and policies. Due to the realization of collaborative services as operations on the model, no specific network collaboration protocol is required. We present an optimistic synchronization scheme which provides consistency for the distributed model.