Constraints-Driven Service Composition in Mobile Cloud Computing

The development of mobile computing and cloud computing enables people to invoke various services from their mobile devices. This paper focuses on the problem of service composition with temporal and QoS constraints in mobile cloud computing. This problem indeed becomes dramatically tough due to the mobility environment, local-time constraints and global QoS constraints as well. This study aims to form such a service composition that not only satisfies both the time constraints and QoS constraints in a mobile service composition, but also ensures the composition to be executed successfully to the greatest extent in the uncertain mobile environment. Firstly, it formally defines the problem and then transfers the problem into a constrained optimization problem and proves it to be an NP-hard problem. To solve this problem, it proposes a differential evolutionary for constraint driven service composition algorithm (DE4CDSC). It first utilizes a constraints based service filtering process to reduce the searching space and then adopts a differential evolutionary based algorithm to form a service combination by maximizing its successful probability after considering service providers' mobility. To evaluate the proposed approach, a series of simulation experiments and comparisons are conducted to demonstrate the effectiveness of the proposed approach.