移动计算环境下不确定性组合服务的事务建模与执行分析
摘要
In mobile-enabled service-oriented computing, there exist resource restrictions and connection intermittences, and transactional services are often confronted with handovers and weak consistency support. In order to ensure the transaction validity of composition services in mobile environments, a mobile composition transaction model based on Markov Chain is proposed via analyzing service uncertainty and transaction properties. Firstly, formal methods are applied to construct a mobile atomic service model and a transaction mechanism of atomic services, and the service uncertainties are formulated with state probabilities. Secondly, the mobile composition service model is constructed using a Markov Chain, in which uncertainties are passed and a method of reliable composition transaction is presented. Then transaction execution of typical logic structure is introduced after execution semantic analysis. Finally, an application case shows that this model is effective to describe the mobile composition transaction, and the experimental results suggest that service availability, service reliability and transaction pattern have a considerable impact on the probability of success of composition transactions.