A network management apparatus and method for determining the topology of
a network in which a Spanning-Tree protocol is implemented, is disclosed
in which address table data is obtained from the ports of the core
network devices on the network, and the identity of the ports of the core
network devices are determined. Spanning-Tree protocol information is
obtained from the core network devices and used to process the address
table data to remove data relating to ports having links which are
inactive. The topology of the network is then determined using the
processed data by first selecting one of the core network devices as a
root network device, and then using the processed address table data to
build a network tree from the selected root device.