Opportunistic Composition of Sequentially-Connected Services in Mobile Computing Environments

摘要

Dynamic service composition has emerged as a promising approach to build complex runtime-adaptable applications as it allows for binding service providers only shortly before service execution. However, the dynamic and ad hoc nature of mobile computing environments poses a significant challenge for dynamic service composition. In particular, the lack of central control and the potential volatility of service providers increase the complexity and failure probability of the composition process. Although, current research has led to decentralised composition algorithms and failure recovery strategies, the key question of how to reduce the failure probability of a composition still remains. We address this question and propose opportunistic service composition, an optimised execution model for complex service requests. The model merges the execution phase into the dynamic binding phase and supports the immediate fulfilment of partially composed service requests. We evaluated our model in mobile ad hoc network simulations. The results show an improvement over a baseline approach regarding composition success, response time, and communication effort.