Extended RBAC model and application

The traditional RBAC model has two disadvantages,the permission-control is a little coarse and is not enough convenient for further software reuse.To resolve these problems,an extended RBAC model is put forward.The ranks of permission is refined and the process of permission-control with meta-data is described.The model can implement dynamic configuration of permission,and improve software reusability.The modelhas been applied to a software project in an enterprise,which proves that itis one correct and effective model.