In this paper

we present two novel algorithms

one for discovery logical topology

the other one for discovering physical topology in heterogeneous IP networks.The algorithm for logical network

which adopt heurism＼greedy algorithms

can be applied to large scale IP network.For the algorithm can self deduce IP addresses

adjust the search domain

it has strong adaptabilities.Another novel algorithm is presented for physical topology which includes switches

hosts and hubs.At the same time

a new data structure named Treelike

-

Graphics for topology discovery is presented with precise mathematic definition

relationship set and proprietary operation on this data structure.The algorithm

which we present in this paper

does no base on the STP protocol to get the information of topology.So

there are few preconditions to the algorithm.We have im

plemented the algorithm presented in this paper in Perl in Tsinghua University own research network.The experimental results clearly validate our algorithm

demonstrating that our algorithm can consistently discover the accurate physical network topology with reasonably small running-time requirements.