Node-merging method in passive network topology detection

In order to establish a clear picture of Internet topology, our Node-Merging Method (NMM) tries to make use of only the protocol information between two nodes, especially the hop count. When remaining the minimum hop of two nodes unchanged, a complex and redundant network, reconstructed by using hop information, can be simplified into a simple one without any redundancy. In the basis to remain the minimum hop unchanged, it can be inferred into two simple criteria to reduce the algorithm complexity, without computing every minimum hop of node pairs. It can also be proofed the two criteria is a necessary and sufficient condition. After finding out the whole node pairs that can be merged, we come up with a strategy called MAX to tell which pair to select. Finally, it is shown by simulation that NMM is available when only hop information is offered.