Managing Network Troubles while Interacting within Collaborative Virtual Environments

We are interested in real time collaborative interactions within Collaborative Virtual Environments (CVE). This domain relies on the low latency offered by high speed networks. Participants of networked collaborative virtual environments can suffer from misunderstanding weird behavior of some objects of the virtual universe, especially when low level network troubles occur during a collaborative session. Our aim is to make such a virtual world easier to understand by using some graphic visualizations (dedicated 3D metaphors) in such a way that the users become aware of these problems and can go on working even during these troubles. In this paper we present how two independent mechanisms may be coupled together for a better management and awareness of network troubles while interacting within a networked collaborative virtual environment. The first mechanism is an awareness system that visualizes, through the use of special metaphors, the existence of a network trouble as strong delay or disconnection. The second mechanism is a virtual object migration system that allows the migration of an object from one site to another to ensure a non interrupted manipulation in case of network troubles. We will detail only this awareness system and we will show how it uses the migration system to allow users to go on interacting while network breakdowns occur.