Research On Energy Efficient Data Access In Mobile Peer-to-Peer Network Environment

In mobile P2P networks, the peer-to-peer way of direct access is used to conduct data access between nodes without the need for the intermediate server involved that solves the problem of load uneven、 concentrated congestion and so on in the C/S architecture network, takes full advantage of the potential resource implicated by a number of mobile node. At present, has been a lot of literature researched processing method for distributed data query based on broadcast mobile P2P networks, but most of research only consider the broadcast of data without considering the limited resource of mobile node(such as power resource, processor resource, memory resource, etc). Therefore this thesis researches how to reduce the energy consumption of mobile node in the process of data access based on the location aware query in mobile P2P networks.This thesis describes the construction principle、query algorithm of R-Tree spatial index which is the most commonly used energy-saving technology as well as working principle of three kinds of data access way in detail. For the defects of R-Tree spatial index like the long access time, the high energy consumption when it is used to conduct data access, We design a Distributed Spatial Index Based on minimum boundary Rectangular (BRDSI, for short) which can immediately begin to query and quickly repair query interrupted. Then, we propose a query algorithm of Distributed exponential Sequence Scheme (DSS, for short), that provides query node with the ability of selective tuning broadcast channel. Both of them can minimize the access time, improve query efficiency, reduce energy consumption in mobile device.This thesis not only in theory comparatively analyzes the average energy consumption of BRDSI and R-Tree spatial index, energy consumption of on-demand request method with no spatial index (OA)、 periodic broadcast method with BRDSI (BRDSI_DSS) as well as hybrid access method with BRDSI (BRDSI_HYD), but also in the specialized PeerSim simulation platform, compares BRDSI with R-Tree in average access time and average energy consumption, contrasts OA、BRDSI_DSS and BRDSI_HYD in the size of data、number of users、moving distance and size of cache. theoretical analysis and simulation results show that compared with R-Tree spatial index, BRDSI_DSS has shorter access time and less energy consumption and that BRDSI_DSS and BRDSI_HYD are more energy consumption than OA under any circumstances, because both of them reduce energy consumption via either reducing tuning time of listening to broadcast channel or selectively connecting to a node which has a quality guarantee; BRDSI DSS is suitable for the case of that the size of data is moderate、 the number of concurrent data access users is more and the query node continues to move, BRDSI_HYD is fit for the case of that the size of data is large、the number of concurrent data access users is few and the query node is relatively stable.