Abstract

Access control policies are security policies that govern access to resources. The need for real-time update of such policies while they are in effect and enforcing the changes immediately, arise in many scenarios. Consider, for example, a military environment responding to an international crisis, such as a war. In such situations, countries change strategies necessitating a change of policies. Moreover, the changes to policies must take place in real-time while the policies are in effect. In this paper we address the problem of real-time update of access control policies in the context of a database system. Access control policies, governing access to the data objects, are specified in the form of policy objects. The data objects and policy objects are accessed and modified through transactions. We consider an environment in which different kinds of transactions execute concurrently some of which may be policy update transactions. We propose algorithms for the concurrent and real-time update of security policies. The algorithms differ on the basis of the concurrency provided and the semantic knowledge used.

Author Keywords: Security policies; Concurrency control; Transaction management

Article Outline

1. Introduction

2. Our model

3. A simple algorithm for policy update

Conflicting operations

Policy-secure transaction

4. Towards a semantic-based approach for policy update

4.1. Concurrency control based on knowledge of policy change

5. Semantics-based concurrency control algorithm

Commutativity of transactions

Commute set of ty(T_i)

5.1. Concurrency control mechanism

6. Related work

7. Conclusion and future work

Acknowledgements

Appendix A

References

Vitae