Concurrency Control for Multilevel Secure Databases

A multilevel secure database is intended to protect classified information from unauthorized users based on the classification of the data and the clearances of the users. The concurrency control requirements for transaction processing in multilevel secure database management systems (MLS/DBMSs) are different from those in conventional transaction processing systems. In MLS/DBMSs, coordination of transactions at different security levels is needed to avoid both covert channels and the starvation of high security level transactions. In this paper we outline the transaction processing requirements in MLS/DBMSs, survey the mechanisms proposed to address these requirements and propose a new secure multiversion concurrency control protocol. We also investigate the relative performance of our protocol with existing secure concurrency control protocol while varying workloads. The results show that our protocol achieves a significant performance improvement, in terms of fairness.