Research On Agent-based Grid Services Composition

As a new distributed computing technology, Grid can combine computing resources, data resources and service resources together efficiently and share them according to the requirement in the wide-area network environment. With the character of supporting mass computing, data-intensive processing and group-cooperative work, Grid makes great changes in the obtaining, sharing and using of the resources, influences and even changes scientific research methods and the ways of learning, working and living in people's daily life. With the development and merging between Grid and Service Computing, Grid Computing for service has become an importance research field. However, facing with the more and more complicated requirement of the users, single Grid Service appears a little insufficient. So how to found an efficient and intelligent Grid Services composition method becomes the key point in the research of Grid technology. This paper is mainly devoted to combine Agent and Grid Service Composition together in order to realize autonomous cooperation among Grid Services.First of all, the paper introduces the development and current situation of Grid, SOA, Web Service and Grid Service, analyzes the technological characteristics of SOA, Web Service and Gird Service separately and the relationship among them, explains the definition and classification of Intelligent Agent, BDI model, Communication Mechanism and Multi-Agent System, especially gives a detail description on the formal definition of BDI Model based on Intelligent Agent, explains the generation process and principles of Belief, Desire and Intention, which can be served as the reliable basis for the foundation of multi-Agent Negotiation Mechanism based on BDI.After analyzing the theoretical and technical possibility of combining Grid technology and Agent technology, this paper proposes an ABSC Model---a Grid Service Composition Model based on Agent. This ABSC Model divides Agent into Communication Agent, Negotiation-Initiating Agent, Service-Managing Agent according to their different functions. The advantages of Grid technology and Agent technology are brought into full play in the designing of ABSC Model. Grid gives a stable resource platform for the Agent, and Agent makes the Grid Service Composition more flexible and intelligent. Then, based on Domain Ontology, this paper proposes a multi-level semantic service Matching Algorithm for ABSC Model. It contains category matching, function matching and performance matching. Then the matching ranges are narrowing successively in order to improve the efficiency and precision of service matching.At last, the Negotiation Mechanism based on BDI among multi-Agents in ABSC Model is designed to make sure of the transaction, safety and stability of the Grid Service Composition. And then the corresponding simulation experiments about Negotiation Mechanism are done.