A user-centered, modular authorization service built on an RBAC foundation

Psychological acceptability has been mentioned as a requirement for secure systems for as long as least privilege and fail safe defaults, but until now has been all but ignored in the actual design of secure systems. We place this principle at the center of our design for Adage, an authorization service for distributed applications. We employ usability design techniques to specify and test the features of our authorization language and the corresponding administrative GUI. Our testing results reinforce our initial design center and suggest directions for deployment of our authorization services. A modular architecture allows us to experiment with our design during short term integration, and evolve it for longer term exploration. An RBAC foundation enables coherent design of flexible authorization constraints and queries. We discuss lessons learned from the implementation of this service through a planned deployment in a context that must balance new research in risk management with dependencies on legacy services.