The Research And Implementation On Automatically Discovery And Visualization Of Computer Network Topology

With the rapid development of computer network, the increasing scale of computer networks, the network structure more complex, making the network management and maintenance becomes more difficult. As one of the most basic function of network management, topology discovery is the other network management such as configuration, performance, failure of the foundation, the technology research and implementation for solving the above problems is of great significance. Therefore, topology discovery is important for monitoring the entire network, accessing to the complete network information, ensuring that the network speed, and stable operation.The main purpose of network topology is to acquire and maintain the distribution of network nodes and connections among them., this paper respectively on the network layer and the link layer topology discovery algorithm is analyzed and studied. For the topology discovery of network layer, three algorithms in common use are introduced : The method based on SNMP protocol, the method based on a common protocol and based on OSPF protocol. In the analysis of the existing algorithm, an improved algorithm based on the SNMP protocol is proposed; those can accurately and efficiently discover the backbone of network and devices in the subnet and connectivity between devices. For the topology discovery of data link layer, also introduced two types of commonly used algorithms: Algorithm of using the FDB (Forwarding Database) requires the FDB should be complete. Algorithm of using the STP requires all devices support the STP protocol. The implementations of topology discovery system for the schedule search, custom search for router or subnet, data circumvention are described in detail.Finally, the system has been tested in the real network environment. The correctness, operability and feasibility are verified by comparing with the old algorithms and analyzing the test results for the topology discovery of network layer. Obtain the network topology map more accurate, with strong operability.