Research On The Key Technology On Network Host Discovery

With the improvement of computer technology and network security technology.With the rapid increasing of the network user's security conception and rigorous situation of cyber security,the cyber machine finding technology has become a new research hotspot.The network machine scanning technology have sprung up.The system architecture of cyber is becoming more and more complicated.However,the anti-machine scanning technology and the filtering –tech of the fairwall is fast growing in the mean time.In the real network environment,in order to improve the security of the network,most network topologies use firewalls and filtering devices.At present,in the existing host discovery methods,only a few scanning methods can detect the host behind the firewall,but the overall discovery effect is not very good,the discovery rate is not enough high.Based on the above background and the thought of SYN backlog side channel,the paper proposes an improved host discovery method to solve the problem that the status of proxy host SYN backlog will affect the accuracy and quantity of host discovery.By establishing the SYN backlog status sequence,the method predicts the best time for SYN backlog detection and completes the network host discovery detection at the best time.In addition,the paper also makes detection and judgment on the filtering situation of subnet entrance,and finally gives the conclusion whether the host exists or not comprehensively by using the hypothesis test method in probabilistic science.Relevant experimental results show that the improved method proposed in the paper has improved the detection and accuracy of the network host.This paper follows the software engineering idea to design and implement a network host scanning system.The design process includes the overall implementation goals of the system.Subsequently,the network topology environment,main module division and function of each module of the system are described.The functions of some core modules are described in detail.Finally,the network host scanning system is tested by the black box test method.The test results prove that the function realization of the system is correct.The network host scanning system implemented in this paper can meet the actual needs related to the actual network host discovery.