Research On Chord Protocol In Structured P2P Network

Currently, the key problem in Peer-to-Peer network is how to locate the resources effectively. The proposal of routing algorithm based on DHT has improved it a lot.The paper focuses on detailed research into typical structural P2P routing algorithm-Chord, analyses its basic concepts and characteristics. On this basis, propose some improvements on resources lookup, aiming at decreasing the latency of resource location and optimizing the lookup mode.The first optimization comes to the improvement of lookup mode of original Chord. Since Chord implements single lookup mode, when there are some low efficiency nodes in the network, they will affect the lookup efficiency terribly and cause high latency. So we put forward parallel lookup mode. This will decrease the probability of routing from bad nodes and then increase the lookup efficiency.The second optimization is applying Vivaldi to Chord. Through the sensitivity of physical topology, optimize the lookup strategy.In order to verify the correctness of the theory modification, we use the P2PSim platform to simulate and compare the original protocol and the amendment protocols by the parameters of performance. It. indeed proves that the amendment ways can effectively improve efficiency of resources lookup of Chord protocol. Simulation experiments show that the improvements emphasize particularly on different points, and supplement each other. In one word, these methods can to a certain extent promote the efficiency of researching resources.