The Complexity Of Query Processing In P2p Networks

Along with the development of the Internet and its increasing user number, Peer-to-Peer (P2P) network is attracting more and more attention in the both academe and industry as a new network application mode. In recent years, because of its flexibility on query pattern and adaptability to dynamic environment,it is largely deployed and become the mainstream in the P2P network.In this paper, we study the heterogeneous characteristics and the complex queries in the P2P network, and achieve the following progress: Firstly, through the analysis of heterogeneous nodes in the aspect of processing capability, location and survival time, we design a novel mode for the P2P network, which bases on a small world theoretic.The mode ameliorates the structure of the Chord cicle.We propose the data distributing algorithm to support complex queries, it can shorten time delay and adjust load balancing dynamically in the network . Secondly, we focus on the hotspot of data search in the network, and propose the algorithms of range query and join query in heterogeneous P2P network. In the algorithms of range query, we make full use of the character of heterogeneous geographical location, and duplicate the related data to nodes in area, which can enhance the speed of range query and keep load balancing. In order to solve the problem of join query, we propose Top-k-join algorithm, through sample method, the algorithm get a low bound of result, before the join operation ,it cut down some records which is impossible to get the final result. This method saves a large mount of bandwidth consumption and computing consumption. We also use the result in the cache to deal with new ranked query, this method can reduce the number of data access and the mount of network bandwidth.Finally, we do a lot of simulation experiments, using uniform data sets and Gaussian data sets, to obtain the data statistics and analysis of time delay and load, the availability and feasibility of the algorithms have been fully proved by the simulation experiment result.