Nowadays, network is becoming more and more complicated. Topology discovery becomes a hot research point as it is of high importance to network management. Current topology discovery methods have been investigated in this paper, which can be classified as common-protocol-based method, router-protocol-based method and SNMP protocol-based method, all of which are specifically discussed in the following sections.The advantages, disadvantages and using scope of every method are analyzed and finally a comparison is made. 1 Introduction With the fast development of the network, the network scale and complexity is increasing rapidly, that is why network management is becoming more and more necessary. A topology discovery method with high accuracy and efficiency is the presupposition and guarantee of the network management as it is the basis of the network management. The network topology discovery [1] is a technology that finds out the entities of the network, such as routers, switches, .etc, and clarifies the relationships between them automatically. It is the basic functions of a network management tool and helps a lot on optimizing the network configuration, finding the bottleneck of the network, locating the network faults, discovering the potential dangers and so on. The network topology discovery is widely researched at present. In this paper, a systematic research of current topology discovery methods is investigated. Furthermore, the advantages, disadvantages, and usmg scope of each method are thoroughly analyzed.2 Taxonomy of topology discoveryNetwork topology discovery is one of the core 978-1-4244-6769-3/10/$26.00 ©201O IEEE 186