Proposes a new and effective automatic topology discovery algorithm for Ethernet. The algorithm is based on four theorems for determining the connection between two Ethernet devices. Compared with other approaches to Ethernet topology discovery, this algorithm doesn 't require each bridge has either minimum knowledge or completed forwarding table information. The algorithm has been implemented in the context of a topology discovery tool that has been tested in the research network. The experimental results clearly validate this algorithm, demonstrating that it can accurately discover the Ethernet network topology. 

network management, ethernet, topology discovery, SNMP