Research On Network Target Detection And Access Technology Under Internet Environment

With the growing size of the network, network security problems become more and more serious, and network attacks have a great impact on the usage and management of network. As the foundation of network attack and defense, network target detection and access technologies will help network managers better understand their own safety and then do some preventive measures to nip in the bud. At the same time it has important application value and practical significance for network intrusion detection.This thesis summarizes various network probe scanning techniques including target viability detection, port scanning, operating system detection and network topology detection, and on this basis two different detection schemes are designed and implemented for different targets. For simple target such as a single host, a single host detection scheme, including target viability detection, port scanning and operating system detection, is studied and implemented. For unknown target network with a large number of hosts, first the overall topology of target network is speculated by hierarchical clustering network topology inference method. Then with the help of network topology, other useful information of target network can be got by key nodes’ fine-grained detection and scanning using the aforementioned single host detection scheme. Finally, the single host detection scheme is tested and verified in C#. While the topology detection algorithm for target network is simulated and verified under NS-2 simulation platform, result shows that the algorithm can ensure the high accuracy of topology inference while effectively reduce network measuring flow, and then the efficiency of topology inference is greatly improved.