Research On Trust-aware Resource Trading Mechanism In Grid Market Environments

With the development of computer and communication technologies,network environment has changed from a close network,which is comparatively static and faced with special organizations or user groups,to an open one that can be publicly accessed and faced with many dynamic users.As the representatives of open networks, Grid has become one of the most popular research fields all over the world.Grid is dynamic,heterogeneous and autonomic for resource sharing.Therefore, the rational nodes in the grid are self-interest and try to maximize their own benefit without considering the whole utility of the grid.Each node in grid can both be resource provider and resource user.Every node hopes to use others' resources as many as possible,but contribute their own resources as few as possible,which leads to non-collaborative and dishonest behaviors in the grid.As the network enlarges, resource management and security turn to be more intractable.Thus,market mechanism and trust mechanism become important research area in grid environment.This dissertation discusses unreliable service usability and usability problems resulted from nodes' selfishness in grid environment.The dissertation presents resource pricing strategy and resource allocation mechanism based on trust group, resource trading mechanism based on two-level market,which is resource market and service market.It focuses on stimulating rational and selfish nodes to share resources honestly,so that the network's integrated ability can be improved.Firstly,the dissertation summarizes the existing research status of grid,analyzes the problems of grid to invite the research topics.Subsequently,Chapter 2 introduces the grid market and trust mechanism and points out the existing insufficiencies in such reseach.This chapter also summarizes usage of grid trust mechanism on grid security. and trust value computing methods and trust frameworks.The advantages of using market mechanisms to manage resources and some key issues in G-Tart model,which is a model combining market mechanism with trust mechanism,are also analyzed.Secondly,aiming at the severe information asymmetry problem while pricing resources in grid market,the dissertation introduces trust to resource trading and proposes a differential pricing strategy based on trust group.Nodes select their trade partners according to the trust value of the nodes and their trust groups.The trust value of the resource provider reflects the reliability of its resource.The users can select their providers according to these.That of the users reflects whether the user is a malicious node or selfish node,which can be a refenrence for the resource providers pricing resources.The differential pricing strategy based on trust group can encourage nodes to provider honest resource/service,improve success rate of transactions,and reduce the impact of malicious nodes on the performance of the grid system.Then,in order to solve fairness problems in resource allocation,the dissertation proposes a trust group based resource allocation mechanism combing with admission control.Utility functions of providers and users are built to measure the nodes' income,which takes trust relationship between the nodes into account.To use the providers' resources efficiently and allocate resources fairly among the users, admission control is incorporated in the resource allocation mechanism,which controls the users' resources demand according to the trust value of the users and the number of resources.The mechanism can improve success rate of transactions and resources utilization,and increase benefits of the two trade partners.Finally,the dissertation proposes a trust-aware resource trading mechanism based on two-level market.Aiming at the disadvantages of the recent trust framework, enlightened by two-level market model,the dissertation introduces the concept of the two-level market and gives a two-level market-based trust framework.Based on the trust framework,the dissertation proposes a trust-aware resource trading mechanism. The mechanism can differentiate malicious nodes and selfish nodes,encourage nodes to contribute their resources to the grid system.From the inherent characteristics in grid such as dynamicity,heterogeneity between peers and unreliable resources,this dissertation deeply studies the resource management and trust problems,proposes trust group-based resource differential pricing strategy and resource allocation mechanism,provides a resource trading mechanism based on two-level market.It shows a brand new view and fine perspective for solving the key issues when market mechanism combines with trust mechanism.