Ensuring the Consistent Concurrent Execution of Service Composition under Relaxed Isolation

In web service environment, B2B applications are usually built by composting pre-existing individual services, which are executed across multiple loosely-coupled autonomous organizations. The transactional challenges raised by the composition of services are twofold: relaxed atomicity and relaxed isolation. The relaxed atomicity of composite services can be verified at design stage. However, when multiple verified composite services run concurrently, inconsistency may still appear due to relaxed isolation. In this paper, we propose a concurrency control method to ensure the consistent concurrent execution of multiple transactional service compositions. The global consistent execution of composite services can be achieved through the collaboration among dependent transactions and the services they have accessed under the direction of the concurrency control algorithm. Compared to existing work, the salient feature of the method is that it can ensure the global consistency while supporting the relaxed atomicity of each involved composite service.