Grant: Discovery Grants Program - Individual

Access control is the ability to say who can do what operations on what data; e.g., the shipper in an on-line book store can read a customer address but not update it. Access control takes over after user authentication, deciding what that user is allowed to access, read, write and update (e.g. the shipper should not be inserting new inventory). Customers may be allowed to say that their address can be used for shipping but not for advertising; this is what is commonly referred to as data privacy. Shipping and advertising are examples of privacy purposes. Data concerning the company's inventory is controlled by access control. Customer data, on the other hand, is also subject to privacy concerns. Implementing these privacy requirements, and the tools to express what should be private, are aspects which concern Computer Scientists. Our access control research is based on the role-based access control (RBAC) model where permissions are collected in roles and assigned to users in one operation. RBAC simplifies the management of access control in complex environments, helping the security system designer to do a better job. Some metrics exist to say when a role design is ""good"" (e.g. fewest possible roles); we will search for others. We will study updates to an RBAC design, and tests for desired properties. We have recently studied RBAC with privacy labels on some of the data. We propose to further this research, examining the storage of data with these labels, and the run-time tradeoffs of different physical partitions of the privacy-labeled data, while querying and updating it. The scientific approach involves developing a model, proving properties of the model, showing its applicability to real-world situations, developing prototypes and tools, and performance analysis comparisons. The contributions of the research will be a better understanding of preserving privacy, preserving privacy in the presence of an access control mechanism, maintaining these systems under change, measuring when we have a good design, and more efficiently implementing access control and privacy- preserving systems.