QoS Optimizing Model and Solving for Composite Service in CGSP Job Manager
Hai Jin · Chinese Journal of Computers · 2005
The emerging service grids bring together various distributed services to a ‘market’ for clients to request and enable the integration of services across distributed, heterogeneous, dynamic virtual organizations. Job Manager, a service composition toolkit, is designed in CGSP. In the early experience of constructing and using the Job Manager, the authors found it is a great challenge for the composition service to meet users’ QoS requirement. This paper presents a QoS optimizing model for composition services. Three main features of the model are (1) service virtualization, (2) scalable QoS metrics model, and (3) muti metric based QoS optimization for composite services. The authors design two algorithms for solving the model and compare their optimizing time cost and precision with simulation results. Discussion is also made to advise implementing model in CGSP Job Manager.