In this paper, we implement the access control policies
using RDBAC for student results information system.
Transaction Datalog (TD) [13] is used to write the access
control policies. Furthermore, these policies are implemented
in the SQL. We observed that RDBAC does not consider the
time constraint during expressing the access control policies
e.g. in many organizations, functions may have limited or
periodic temporal duration. Consider, for instance, the
instructor can also act as an exam coordinator in case of
unavailability of designated exam coordinator i.e. the instructor
is acting as instructor (primary function) as well as exam
coordinator (temporal based function) for a specific duration.
Consider another example of medical database systems in
hospitals; the doctor-on-night-duty role is enabled during the
night. Since doctors may need the assistance of a nurse, the
access policy should make sure that the corresponding function
i.e. nurse-on-night-duty is enabled whenever doctor-on-nightduty
is [12].
In order to cope with these types of policies we have to
consider the time constraint. As RDBAC does not explicitly
considers the time constraint therefore, we extended the
RDBAC and presented the idea of Temporal Reflective
Database Access Control (TRDBAC). This model will allow
the policy makers and database administrators to design and
implement time based database access control policies.
The remainder of the paper is organized as follows: In
Section 2, we have discussed the characteristics of DAC,
MAC, RBAC, TRBAC and RDBAC. In section 3, we
discussed how the access control policies be implemented
using the reflective access control model for the student results
information system. Section 4 describes the implementation of
access control policies for student results information system
using the TRDBAC. Finally section 5 presents some
concluding remarks.