Research On Key Security Techniques Of Content Shanring Networks

The security of cyberspace is being a national strategic issue increasingly,and almost all of the countries are highly concerned about the network security of their own countries and their closely associated countries.China is committed to realizing the development goal of being a country with powerful networks and creating a network environment of innovation,coordination,green,openness and sharing.This is also a hot issue in the field of cyberspace security.As a kind of sharing platform for files,information and resources,Content Sharing Network(CSN)possesses a very wide distribution in Internet.It does provide a great convenience for people to share various contents through Internet with the rapid development and wide application of network techniques,especially the emergence and prevalence of P2P(peer-to-peer).However,numerous malicious files,illegal information and spywares have swarmed into the network,which poses a serious threat to the security of CSN.The dissertation focuses on the key techniques related to security,such as measurement,monitoring and mitigation of CSNs.The main work and contributions are as follows:(1)A layered and cyclic architecture reference model of CSN security is proposed.The dissertation discusses the important issues such as concepts,connotations,calssifications,key techniques and development trends in detail combing with the development and research status of CSNs.On this basis,a layered and cyclic architecture reference model is proposed.Through the formal description,we have combed systematically the security modules and functional elements of key techniques in the new normal of CSNs.This model can provide an effective reference for establishing a secure,healthy and green content sharing environment,and is a general guide for studying the key techniques of CSN security.(2)A versatile and cyclic measurement tool for P2 P CSNs is developed.To the best of our knowledge,most of the measurement tools have not been updated under the current situations of P2 P CSNs.The dissertation designs and develops a new,versatile,cyclic P2 P CSN measurement based on a typical P2 P CSN Kad.The continuous experiments and further analysis indicate that the measurement tool can obtain complete snapshots of P2 P CSNs with a higher efficiency by adopting the optimized and adjustable crawling algorithm and strategy.(3)A new cyclic monitoring method based on the deployment Sybils by different domains.Aiming at the seriously inadequate CSN monitoring,the dissertation proposes a new cyclic monitoring method based on the deployment of backbone-Sybil nodes by different domains and the in-depth analysis of a large number of network measurement data.Thus,it forms a comprehensive,continuous and effective hotspot perception and sharing activities monitoring capability for CSNs by enhancing the importance and influence of Sybil nodes,and the effectiveness verifys with theoretical analysis and experimental testing.(4)A malicious content mitigation scheme based on the coordinated deception of backbone-Sybil nodes is proposed.In view of few researches on malicious content mitigation,the dissertation proposes a phased mitigation scheme based on the effective monitoring of malicious content and coordinated deception of backbone-Sybil nodes,and introduces a root-oriented region of index pollution technology at the same time.Then we design and implement a system of malicious content monitoring and mitigation based on Kad with Python programming language.The effectiveness verifys with theoretical proof and experimental analysis.Besides,we discover the core indicator for the performance evaluation of malicious content monitoring and mitigation.The research results of the dissertation have important significance for enhancing the security of CSNs,and provide theoretical basis and technical support for the formation of innovative,coordinated,green,open and shared network environment.