The Research On Tree-Structure Search Mechanism In Gnutella

Gnutella is a representative of decentralized P2P network. Because of its character of entirely distributed and highly dynamic, it can effectively avoid isolation nodes bottleneck, intelligently finding peers, acquire valid information and make network much more robust. And Gnutella haven't such high delay and low efficiency weakness which caused by the structured P2P network for without considering real-time and dynamic of the network. While flooding is used to broadcast query across Gnutella networks, it generates exponentially increasing redundant messages, so that searching efficiency is decreased rapidly , the growth and scalability of P2P system is hindered. So it is one of the mainly study on Gnutella network that improving search efficiency and mending the search mechanism of Gnutella network.This paper takes efficiency improvement of flooding as topic, then makes an extensibility discussion on it, and mainly analyzes the characteristic and deficiency of this mechanism, and introduces its storage mechanism and a algorithm of Gnutella-Tree construct. Attempt to enhance the searching efficiency, to reduce the cost and the redundancy, a new technique called Gnutella-Tree is presented. The idea of this mechanism is that construct dynamically search-tree in the course of searching information. A new Adaptive Gnutella-Tree Algorithm (AGTA) is given, which is used to control the loss of Gnutella net search and net's instability brought with peer exiting or joining, and meanwhile, The experiment shows that Gnutella-Tree and AGTA is available, and it could increase flooding efficiency, reduce redundant messages, and adjust itself to the dynamic change of P2P system causing by constant peer arrivals and departures.