An Algorithm of Physical Network Topology Discovery in Multi VLANs
The most recent physical topology discovery knowledge of the Ethernet network is the key to network management tasks. Virtual LANs (VLANs) allow network managers to completely break the correlation between the logical and physical network by grouping the interfaces of the same network elements into different subnets. An efficient and general algorithm for discovering physical network topology across multi VLANs is very necessary. Our topology discovery algorithms are simple for VLANs if we know the VLANs interface groups. The algorithm based on MIB information of SNMP standard is widely supplied by modern IP network elements and does not need modify the operating system software running on hosts or elements. The experimental results prove the correctness of the algorithm and the sufficient and necessary conditions for the uniqueness of the restored topology.