Refer to http://en.wikipedia.org/wiki/Role-based_access_control
n computer systems security, role-based access control (RBAC)[1][2] is an approach to restricting system access to authorized users. It is used by the majority of enterprises with more than 500 employees,[3] and it is a newer alternative approach to mandatory access control (MAC) and discretionary access control (DAC). RBAC is sometimes referred to as role-based security.