The Application Of Client Puzzle And Trust Mechanisms In The Mobile Internet

The computer network technology has developed from previous local area network, Internetto the current mobile Internet. With the development of wireless access and mobile terminals, themobile Internet has been booming in recent years. The number of users of the mobile Internet hasexceeded that of the traditional Internet, and is still increasing steadily. The research on the mobileInternet has become a hot topic. Meanwhile, security-related issues of the mobile Internet aregradually emerging. The research on security theory and key technology has important practicalsignificance to the development of the mobile Internet users, and the IT industry.In this thesis, based on the Client Puzzle and trust mechanism, we study in detail the terminalprotection strategy and node trust model in the mobile Internet. We propose three specific securityschemes. The content of this thesis involves network communication protocols, simulations,mathematical modeling and other technical fields. The main research work includes the followingthree aspects:(1)The usage of the Client Puzzle mechanism in the mobile Internet is studied. After athorough study on the Client Puzzle mechanism and security features of mobile terminals, wedesign a Willing-based Access Control Model (WACM) for mobile terminals with the ClientPuzzle. WACM is aiming at frequent communications and easily harassment characteristics ofmobile terminals. In WACM, destination nodes confirm the willingness of access of source nodesby sending puzzles to sources and validating corresponding answers, then decide whether or not tocommunicate with source nodes.(2)Participation Trust: a trust model based on participation in mobile P2P networks. P2P isone core technologies of the Internet, and has been widely popularized and promoted for numerousapplications. It has good practical significance to apply P2P into the mobile Internet to enhance theapplicability of the mobile Internet. The research of trust is one of the foundations of P2P networksecurity. In order to apply P2P to the mobile Internet, we must firstly solve the trust problembetween nodes of a mobile P2P network. This thesis proposes the concept of participation of nodewhich is used to measure the level of activity of the node in the behavior of the transaction andtrust management in the network. We design a trust model based on participation in a mobile P2Pnetwork to limit the malicious nodes and protect legitimate mobile nodes. (3)MTM: Mobile Internet trust model based on willingness and participation. We propose atrust model in the mobile Internet based on willing and participation. Firstly we divide the mobileInternet into several virtual subnets covered by base stations, and then deploy distributed networktrust model based on the willing and participation in each subnet. Finally we propose the conceptof Trust Management Center (TMC), which is used to backup trust data and manage trustcommunications between virtual subnets.Simulation results in mobile terminals show that the WACM can effectively protect themobile terminals users from harassments. With the PeerSim software, the simulation results showthat the trust model proposed in this thesis can limit the activities of malicious nodes in mobile P2Pnetworks, thus improves the communication success rate between mobile P2P nodes. The securitymechanisms proposed in this thesis can be used to enhance the security of the mobile Internet, andcontribute to the development of the mobile Internet.