On supporting user-defined collaborative workspaces over cloud storage

We introduce a novel cloud storage service named Uspace supporting the concept of user-defined collaborative workspace which provides the functionality of inviting unregistered people as group members and assigning appropriate access rights to them. Uspace is developed by extending the Swift storage service included in the OpenStack cloud computing system. In addition, Uspace provides a concurrency control service for coordinating resource accesses which is necessary for collaborative applications. As one of applications utilizing the Uspace service, we also present an Android application UspaceApp equipped with the features of shared whiteboards, group chats and file sharing among group members.