Improved algorithm for network topology discovery based on STP

Topology discovery is an important foundation for network management. The existing algorithms get spanning tree status information of each switch by SNMP. This paper proposes an improved physical topology discovery algorithm realized by Perl language. The algorithm does not require that the FDB information of each bridge is complete. Meanwhile, it can find backup link and equipments that do not support SNMP such as hub and dump switches. Experiments show that the algorithm is an accurate, comprehensive topology discovery algorithm.