Who is who: On visualizing organizational models in Collaborative Systems

Access control constitutes a key technology to fulfill security requirements in Collaborative Systems (CS) by specifying access rules/rights based on organizational models that capture the structure of the participating organizations. Organizational structures and consequently the describing organizational models can become complex comprising up to thousands of involved entities and relations. Further on, the management of organizational models is no longer only confined to specialists. Hence it becomes crucial to support the management of organizational information by adequate visualizations. Specifically, querying organizational models by, for example, finding out the number of associated actors to a specific role, has to be designed in a user-friendly way in order to avoid misunderstandings or even errors. As organizations are very likely to change over time, the user-friendly presentation of the related organizational models becomes even more important. This paper presents two novel visualization approaches called OrbitFlower and OrbitList for the analysis and management of organizational models in CS. Both approaches are evaluated with experts in regard to understandability of assignments of users to their roles/organizational units and visual properties.