Topology Measurement And Security Analysis On Gnutella And EMule Network

The application of P2P network has been the largest part of traffic on the Internet, with the growing of P2P networks, the P2P stays as a hot topic in the research fields. P2P overlay network has its own topology characters and network dynamics; it is an important job to analyze P2P overlay network characters in the research field of complex networks. The results we got from analysis can instruct us optimizing node's routing methods, leveling up query speed, reconstructing topology and solving some P2P security problems.Gnutella and eMule are two of the most popular P2P overlay network on the Internet, and they can represent P2P network to a certain extent. On the other hand, these two protocols are both open and free for users, as well as their client software, Limewire and eMule VeryCD. Therefore, we can analyze these networks with the least hurdles. After developing for several years, these two networks become more and more stable and have many new features. The nodes in Gnutella are divided into two-level, Ultra peers and Leaves; while Kademlia protocol is added into eMule. Even the topology of Gnutella has changed as a result.We analyze the detail of Gnutella and eMule protocols,and improve the distributed crawling systems respectively with active measuring method. Using this crawler, We get the topology of Gnutella and eMule with high performance. In the end, we analyze the flaw and security of P2P network, enumerating several situations and give some solutions.The most contributions of this paper include: (1) we develop and improve a high-speed distributed crawler for Gnutella; (2) we design and develop a crawler for eMule. (3) we analyze the security of P2P network and propose some solutions.