Abstract:
As distributed networks become more popular, the need for improvement in distributed database management systems becomes even more important. The most important of these factors of distributed database are single level and multilevel access controls, protection against inference, and maintenance of integrity. In this paper we propose the strategies for concurrency control of global transactions in heterogeneous distributed database systems using the combination of optimistic and pessimistic approaches. The former intends to provide a high degree of concurrency among global transactions, while the latter is concerned with aborts of global transactions. The strengths and weaknesses of the two approaches are discussed. And then we discuss the combination of these two approaches.
