Heuristic-based Web Service Composition Algorithm Research And System Design

With rapid development of web services and growing number of web services,a single web services is unable to meet customer requirements very well.How to take many web services composed together and generate web services composition to meet the growing needs of customer has already been the focus of current research.In this paper, taking such features as a large-scale web services composition contains the large number of web services, the wide covering of range, the complicated of relationship and others into consideration, begin with the functional heuristic strategy, a heuristic web services composition algorithm based on successor cost function(SCF) has been proposed.In the process of a large scale of web services composition,SCF heuristic selects web services and dynamic composes web services based on funcational propertys,using the functional of characteristics,rapidly generates a solution based on functional property, effectively solves business logic of web services composition.Taking into the non-functional of comtomers'requirements consideration, especially the different demands of quality of services,this paper discusses the model of QoS,proposes a web services composition algorithm based on genetic algorithm (SCGA).In the a large scale of web services which have the same functional of propertys but the different non-functional of propertys,this algorithm heuristic selects web services and dynamic composes web services based on non-functional of property. This algorithm solves the customer's non-functional requirements,and optimize the web services composition,based on satisfied the functional of requirements.Taking the current problems of web services framework into account, especially the deficiency of web services composition, this paper designs a middleware Proxy which realized SCF and SCGA algorithm.Through combining the current of web services framework with Proxy module, a new type of web services composition framework has been designed.This paper designs a heuristic based on this framework web services composition system which can better complish business logic of web services composition and the optimization of QoS.