Enhancing group communication systems with mobility support

The vision of ubiquitous communication is driven by increasing user mobility and the need to collaborate. Processes and workflows that were previously bound to stationary computer systems are increasingly being adapted for mobile devices. Mobile collaborative applications, such as video conferences, collaborative writing, and gaming, are already important parts of human interaction. These kinds of applications intensively use group communication. Legacy group communication systems are rarely applicable in mobile scenarios due to temporary communication outages, mobile and nomadic users, and limited device capabilities. Non-responding users are usually associated with node failures and excluded from the group in these systems. In this paper, we argue for the need of a mobility support as a primary service in mobile group communication systems. We analyze mobility issues for mobile collaboration and show that it is difficult to find a generic solution that meets the various requirements to group communication. Using the group communication protocol Moversight as an example, we show how mobility support can be assured for closed group scenarios.