National Institute of Standards and Technology: "An Introduction to Role-Based Access Control"

Read this page about role-based access control (RBAC), a technical means for controlling access to computer resources.

Click http://web.archive.org/web/20160312114733/http://csrc.nist.gov/groups/SNS/rbac/documents/design_implementation/Intro_role_based_access.htm link to open resource.