Role based access control (RBAC) model provides a means of efficient management of access control policy in large scale and widely distributed environment. With policy-neutral architecture and flexible constraints, RBAC can be configured to enforce various access control policies. However many access control policies cannot be configured with standard RBAC model. The framework of context active RBAC is presented, which enhance the expressiveness of RBAC greatly. In context active RBAC the access control decision is also depend on the context and the policy may change according to the context. Novel configurations for simulation of LBAC policies are proposed using context active RBAC.