HCC-Small:Collaborative Mixed-Initiative Access Control

Principal Investigator: Prasun Dewan
Funding Agency: National Science Foundation
Agency Number: IIS-0810861

Abstract
We investigate here the idea of using special-purpose collaborative environments to distribute access. In these environments, the initiative in distributing access rights to shared objects can be taken by information guardians, information consumers, and tools that act as agents of the guardians and consumers. Information consumers will be responsible for sending access requests to information guardians; their agents will (partially or completely) automate this task for them. Information guardians will be responsible for authorizing accesses; their agents will automate this task for them. Intellectual merit We will develop a general model of access distribution that captures in-use and promising mixed-initiative schemes that have so far been defined only in an application-dependent fashion. The model will be defined using several new kinds of application-independent objects such as access requests and grants that capture the information exchanged in a mixedinitiative system. It will be compatible with existing authorization models including objectbased models, in which copies of objects are granted, and rights-based models such as rolebased access control, in which (potentially revocable) rights to the object granted. We will identify a general architecture for implementing this model in which the accessawareness in existing collaboration and communication tools is kept low. In addition, we will develop programming abstractions that make it easy to implement the model using the architecture. We will use the abstractions to add mixed-initiative access control in several target systems, which will include both complex widely-used traditional file systems and distributed web services. This experience will help us evaluate the programmability of the abstractions. In addition, we will perform field and lab studies to compare alternative approaches to distribute access supported by our general model. Because of the diversity of the components of our research, we have assembled a team whose members have expertise in different aspects (systems, user interfaces, agents) of this work. This proposal arises from preliminary research done on mixed-initiative access control by the three team members. Broader Impact Short-term: The project will develop research and teaching software consisting of two main components: (1) layers on top of widely-used file systems that provide several new access distribution schemes, which can be evaluated by usability researchers and demonstrated in classes on security; (2) programming abstractions allowing the incorporation of these schemes in new shared environments implemented using web services, which can be used in both class and research projects. All three researchers on this project have a track record of creating useful, usable, and well-published software systems that have been used as vehicles for teaching and/or research. Long-term: Today, we are faced with three apparently conflicting problems. (1) Users are afraid to collaborate unless they have fine-grained control over how their data are accessed by others. (2) Many shared environments, especially the new ones, do not offer such controls because of the difficulty of implementing them. (3) Those that do offer such controls provide access mechanisms that are difficult to understand and use and result in users being assigned wrong access rights. If successful, our work will show that collaborative systems are not only a liability for access control but also an asset. It could lead to significant improvement in the usability and programmability of fine-grained authorization mechanisms, thereby facilitating a large number of collaborations that would otherwise not take place. It could also provide a better understanding of the similarities and differences between different access distribution schemes and the consequences of using them. Finally, it could result in a new research area focusing on collaborative mixed-initiative access control. Keywords: information privacy; access control; protection; collaboration; mixedinitiative dialogues; revocation; active mail; model; architecture; roles; inheritance