A reliable trading service in open distributed systems

The trading function is an important function which specifies the trading service in open distributed systems. A trader is an object which provides the trading service. In the client-server model, the trader allows clients to locate servers dynamically and allows servers to advertise their services. A reliable trader is particularly important, because if the trader fails, clients could not find suitable servers and servers could not advertise their services. The primary goal of the research is to improve reliability of a trader. To achieve this goal, a distributed system model is proposed which allows traders to provide a reliable trading service. A mechanism is also developed which makes traders tolerant to process failures, site failures, and most importantly, network partitionings. When network partitionings occur, the mechanism uses the semantic information of trader´s operations to maintain the consistency of trader database replicas. Besides providing high reliability, the mechanisms provide higher availability than other proposed consistency control algorithms, such as the weighted voting algorithm. They also provide failure and location transparent trading services to clients and servers