The Technology Of Packet Sniffer And Reassembling Based On Remote Network

In recent years, with the rapid popularization of the Internet, the network service has entered every household, and network communications have gradually become the preferred method of communication. Massive amounts of information flows with a large number in the network. It brings the convenience to people's work, study, and lives. However, with the enrichment and development of network applications, it causes important information disclosure, identity tampering counterfeiting, poor information dissemination and other issues becoming increasingly common. Many criminals attempt to derive the economic and business intelligence in order to obtain illicit personal interests, which seriously disrupted the normal social order, and causing harm to national interests. Therefore, the use of network monitoring technology is necessary for reducing the negative effects of the network. But traditional sniffing technology can be only worked well in Ethernet, which restrict the usage of sniffing badly.This thesis designed and implemented a remote packet sniffing model based on well studying and analyzing the technology of network sniffing and protocol analysis. The system can work in WAN and analyze network packets flexibly and powerfully.This thesis primarily focuses on the following:(1) High performance network sniffing and packet capture technology. This is the foundation of network security monitoring technology as well as the remote sniffing. This thesis puts forward a new remote packet sniffing technology based on the traditional one.(2) Flexible Client/Server model. This thesis presents an effective client/server model. According to the target host setting packet monitoring/forwarding program, the local listening client can receive packets from remote target through the connection between client and server to achieve the monitoring function on the remote host.(3) Multimedia files capture of E-mail. Compared with traditional pattern matching of data analysis techniques, this thesis capturing data contents not only proceed from the SMTP/POP3 protocol but also extend to the multimedia information such as images.Through the research above, the model considering the accuracy, real-time, high performance, adaptability, security requirements and data design principles of readability, this thesis designs and implements a new remote network sniffing model which can cross the gateway and router to the remote host, remote subnet to monitor the work. Network data analysis technology can restore the target of the original data.