Service Provision Control in Federated Service Providing Systems

摘要

Different from traditional P2P systems, individuals nodes of a Federated Service Providing (FSP) system play a more active role by offering a variety of domain-specific services. The service provision control (SPC) problem is an important problem of the FSP system and will be tackled in this paper within a stochastic optimization framework through several steps. The first step focuses on using stochastic differential equations (SDEs) to model and analyze the dynamic evolution of the service demand. Driven by the SDE model, expected future performance of a FSP system is analytically evaluated in the second step. Step three utilizes the differential evolution (DE) algorithm to identify near-optimal service-providing policies for each node. The service subscription protocol is further proposed in step four to help every node adjust its local policy in accordance with the services provided by other nodes. The four steps together implement a complete solution of the SPC problem and will be called the SDE-based service-provision control (SSPC) mechanism in this paper. Experimental evaluation of the mechanism has been reported in the paper. The results show that our approach is effective in tackling the SPC problem and may be therefore suitable for many practical applications.