Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial o...Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial or-ganizations have adopted it, its importance is more and more apparent. In this paper we illuminates the distinctionsand similarities of role and user groups, and based the model that was proposed by Sandhu, we examine the relation-ship of role hierarchies and role constraints and formally describes that, and explain the most important part of roleconstraints ,which is separation of duties.展开更多
文摘Role based access control (RBAC)was proposed in 70's, and prevailed in 90's, and then Sandhu etc pro-posed formal RBAC model. Now RBAC is attracting increasing attention, and many governmental and commercial or-ganizations have adopted it, its importance is more and more apparent. In this paper we illuminates the distinctionsand similarities of role and user groups, and based the model that was proposed by Sandhu, we examine the relation-ship of role hierarchies and role constraints and formally describes that, and explain the most important part of roleconstraints ,which is separation of duties.