Abstract: A multi-segment agent topology mechanism for use by multi-segment network devices in an Ethernet network. Topology information packets exchanged between topology agents in a network include segment identifier information as well as IP address of the sending agent. A device's topology agent maintains and updates topology information in topology tables which identifies interconnected network devices, such as concentrators and bridges, by IP address and segment identifier information as well as incoming slot and port information for eventual use by a network management system in evaluating a networks topology map, and in automatically determining changes in the network's topology.