DyChord: A Dynamic Self-Adjusted Structure P2P Network

Nowadays, the exponential growth in network bandwidth and computing capacity inspire a whole new class of distributed application, peer-to-peer application infrastructures. Peer-to-peer network has many interesting technical aspects such as decentralized control, self-organization, adaptation and scalability. Because of this, the P2P network has become a promising choice of harnessing the huge resources of vast numbers of Internet hosts.The P2P network mainly includes two styles: Unstructured P2P network and Structured P2P network. Unstructured P2P network chiefly contains Central Coordinate Architecture, Sheer Distributed Architecture and Mixed Architecture. On the other hand, Structured P2P network mainly based on Distributed Hash Table, DHT。Like other distributed systems, the core operation in most peer-to-peer network is efficient location of data items in decentralized networks. Due to the decentralized property of peer-to-peer systems, decentralized object location schemes should be promising alternative to traditional approaches. However, Unstructured P2P network cannot achieve the high routing efficiency, while Structured P2P network based on DHT has the properties of high routing efficiency and strong expansibility, which make it being increasingly populated. The dissertation concentrated on the study of decentralized location and routing algorithm in P2P network is the theory foundation for constructing scalable, self-organizing and fault-tolerant peer-to-peer network. The research achievement can also be used to resolve related problems in other distributed systems, such as resource discovery and register protocol in GRID computing, decentralized, scalable and fault-tolerant DNS, Web sever cluster, distributed storage system, et al.This paper firstly investigated the routing algorithm on structured P2P network, such as pastry, Tapestry, CAN and Chord. Especially, Chord and other further Algorithms based on Chord such as HLC, EChord, TCS-Chord and AChord were being deeply investigated, and the limitations of these algorithms were discussed.Then, based on the analysis above, a new routing algorithm DyChord, was brought forward. By analyzing the routing delay in the P2P network, the DyChord changes the resources of two peers, to successfully decrease the delay on routing speed.Finally, by the researches on BRITE P2P emulation system, the DyChord primitive system was designed and realized. After the effective experiments on the DyChord primitive system, the experimental results demonstrate the practicability of DyChord.