Research Of Topology Generation Method Based On IPv6-v4 Coexisting Networks

With the rapid development of computer network applications, IPv4-based Internet has made tremendous achievements. But, with the network fast developing, the limitation of Internet network based on IPv4 protocol is revealed, especially the poor IP address. A new technology is produced to solve the question of network with large scale address. By the IPv6 quickly developing, it would become one of the most important technologies. As the two protocols are not compatible and would coexist in a long-term. So it is not just a simple upgrade from IPv4 to IPv6, and would make network become more complex. The topology of the network is the most important aspect of the network management. Therefore, in the realization of network management, how to discover and manage network topology automatically becomes a new problem. And it is also the kernel of this paper.Firstly, this paper describes the characteristics of IPv6 network and major technology. Through researching campus CPN topology features and referring to the principle of CPN transition, a transition program for CPN is designed.Then, by researching and analyzing the methods of the existing network topology discovery, combining of the characteristics of the Coexisting-environment network topology, a new network topology algorithm for automatic discovery is presented. This algorithm discovers the target network topology with SNMP protocol from network layer and physical layer. Network layer topology discovery algorithm is studied on the network layer elements in the Coexisting networks (such as routers, subnets and transition elements). At the same time, the issues (such as incomplete routing, algorithm efficiency, the algorithm compatibility and other issues) are studied and improved. Physical layer topology discovery algorithm is mainly working for the elements of the link layer in subnets. The issues of the topology discovery (such as the dumb network devices and virtual switch) are studied and improved.Finally, based on the above studies, the prototype system of the co-existent environment topology discovery is presented. The system, including the network layer topology discovery module, the physical layer topology discovery module, tunnel found module and the topology display module, is achieved. At the same time, the system has been applied to our school's campus network and achieved good results.