Design And Implementation On IPv4/IPv6 Data Stream Generated System

With the rapid Internet development in China, network structure is becoming more and more complex. Telecom service providers need monitoring system through reliable and effective network business flow for analysis, and then find network resources potential, reduce network interconnection cost, and provide fundament for the network planning and optimization and their own business development. Therefore, flow based technology in network transmission is used more and more widely. At the same time, along with the quantities of network data, improving the generating rate of data flow is also becoming increasingly important.IPv6, also called the next generation Internet protocols in China, is to solve some insufficiency of IPv4 protocol. It also proposes some improvement in many aspects, such as expanding the address space, simplifying the header, and enhancing the safety. Therefore, it's a trend for transition from IPv4 network to IPv6 network. Due to the wide deployment of IPv4, the transition will be a long-term process. Before this, it will be a long period when IPv6 coexist with IPv4. Therefore, it is meaningful to support the data stream generation in the period of transition.The purpose of this project is to establish a network data flow formation system that support IPv4 and IPv6. Through capturing the packets in high-speed network, generates four kinds of network streams in transitional period, then inserts those to hash table. Through the judgement to timestamp, output the outdated flow into standard data format. It can output to 3 data formats, namely NetFlow v5, NetFlow v9 and IPFix. In addition, supporting both IPv4 and IPv6 protocol, it has very good compatibility. System functions can be divided into four modules, including the capture of data packet, data flow formation, data flow export, and data flow storage. First, system uses capture technology to capture packets from network, and then generates network flow, third, export flows into the collector, in order to store and analyze, in accordance with a custom, extensible formats.This paper firstly introduces the definition of "flow", namely, through the following fields of packet to unique identify a flow:source IP address, destination IP address, transport layer protocol type, source port, destination port, then describes the IPv6 characteristic, as well as the significance for supporting data flow exporting system. In addition, introduces the four modules of system, specially the generation and export modules, and how to output the data flow into a standard format, such as NetFlow v5, NetFlow v9 and IPFix, in order to facilitate network administrator to research network traffic. Finally designs testing environment and testing method, proves that the research on network traffic analysis has the great significance.