QoS-A ware service selection for web service composition

Composition of web services is one of the flexible and easiest approaches for creating composite services that fulfill complex tasks. Together with providing convenience in creation of new software applications, service composition has various challenges. One of them is the satisfaction of user-defined Quality of Service (QoS) requirements while selecting services for a composition. Load balancing issue is another challenge as uncontrolled workload may lead to violation of service providers’ QoS declarations. This thesis work proposes a QoS aware method for optimum service composition while taking into account load balancing. M/M/C queuing model is utilized for the individual services to determine sojourn time distribution for possible compositions. Percentile of the execution time, price and availability are considered as QoS parameters. Proposed algorithm selects the optimum composition according to QoS constraints and utility provided by the services. The performance of the method is evaluated by custom simulation software and is compared to two other methods, random selection and average execution timebased optimal service selection.M.S. - Master of Scienc

Load Balancing and Stability Issues in Algorithms for Service Composition

Service composition enables flexible creation of new services by assembling independent service components. We are focused on the scenario where such composition takes place across the wide-area Internet. We envision independent providers deploying and managing service instances and portal providers composing them to quickly enable new applications in nextgeneration networks