Discovering Network Topology of Large Multisubnet Ethernet Networks

In this paper we investigate the problem of finding the physical layer network topology of large, heterogeneous multisubnet Ethernet networks that may include uncooperative network elements. Our approach utilizes only generic MIB information and does not require any hardware or software modifications of the underlying network elements. We propose here the first O(n³) algorithm that guarantees discovering a topology that is compatible with the given set of input MIBs, provided that the input is complete. We prove the correctness of the algorithms and the necessary and sufficient conditions for the uniqueness of the restored topology. Finally, we demonstrate the application of the algorithm on several examples.