Design issues for oor control protocols

Floor control allows users of networked multimedia applications to remotely share resources like cursors, data views, video and audio channels, or entire applications without access con icts. Floors are mutually exclusive permissions, granted dynamically to collaborating users, mitigating race conditions and guaranteeing fair and deadlock-free resource access. Although oor control is an early concept within computer-supported cooperative work, no framework exists and current oor control mechanisms are often limited to simple objects. While small-scale collaboration can be facilitated by social conventions, the importance of oors becomes evident for large-scale application sharing and teleconferencing orchestration. In this paper, the concept of a scalable session protocol is enhanced with oor control. Characteristics of collaborative environments are discussed, and session and oor control are discerned. The system's and user's requirements perspectives are discussed, including distributed storage policies, packet structure and user-interface design for oor presentation, manipulation, and triggering conditions for oor migration. Interaction stages between users, and scenarios of participant withdrawal, late joins, and establishment of subgroups are elicited with respect to oor generation, bookkeeping, and passing. An API is proposed to standardize and integrate oor control among shared applications. Finally, a concise classi cation for existing systems with a notion of oor control is introduced.