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Gossip-Based Indexing Ring Topology for 2-Dimension Spatial Data in Overlay networks

Procedia Engineering 2012年 29卷 3727-3731页

作者： Z.Q. Zou Y. Wang B. Hu R.C. Wang College of Computer Nanjing University of Posts and TelecommunicationsNanjing Jiangsu 210003 China Jiangsu High Technology Research Key Laboratory for Wireless Sensor Networks Nanjing Jiangsu 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education Jiangsu Province Nanjing Jiangsu 210003 China Key Laboratory of Virtual Geographic Environment Ministry of Education Nanjing Normal University Nanjing 210046 China

Overlay networks are used widely in the Internet, such as retrieval and share of files, multimedia games and so on. However, in distributed system, the retrieval and share of 2-dimension spatial data still have some difficult problems and can not solve the complex retrieval of 2-dimension spatial data efficiently. This article presents a new indexing overlay networks, named 2D-Ring, which is the ring topology based on gossip for 2-dimension spatial data. The peers in our overlay networks exchange the information periodically and update each local view by constructing algorithm. 2-dimension spatial data is divided by quad-tree and mapped into control points, which are hashed into 2D-Ring by SHA-1 hash function. In such way, the problem of 2-dimension spatial data indexing is converted to the problem of searching peers in the 2D-Ring. A large of extensive experiments show that the time complexity of constructing algorithm of 2D-Ring can reach convergence logarithmically as a function of the network size and hold higher hit rate and lower query delay.

关键词： Overlay networks 2-Dimension Spatial Data Indexing Gossip

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Resource Allocation Scheme for Device-to-Device communication Underlying LTE Downlink network

Resource Allocation Scheme for Device-to-Device Communicatio...

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International Conference on wireless communications and Signal Processing

作者： Ran An Jun Sun Su Zhao Shixiang Shao Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education (Nanjing University of Posts & Telecommunications)

ISBN: (纸本)9781467358309

Future cellular networks such as IMT-Advanced are expected to allow Device-to-Device (D2D) communication as an underlay. During the downlink period, both of the D2D receiver and cellular user will suffer from interference caused by radio resource sharing. In this paper, a joint resource allocation and resource reuse scheme is investigated, in which resource allocation to cellular users is employed on proportional fair algorithm and resource reuse to D2D users is employed on a greedy heuristic algorithm. The greedy heuristic algorithm determines the D2D mode is appropriate or not by path loss comparison, then decreases the interference to cellular user by selection of the minimum channel gain between cellular user and D2D transmitter each time. System simulations in two different scenarios demonstrate that sum throughput of cellular user and D2D pair is improved using the proposed scheme, and the interference to cellular user is under control.

关键词： Device-to-Device resource allocation mode selection resource reuse interference control

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IOT platform-oriented Socket design and optimization

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Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and technology Edition) 2012年第SUPPL. 1期42卷 290-294页

作者： Wang, Kun Yu, Yue Zhang, Yu-Hua Guo, Huang Wang, Lin-Lin Key Lab. of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

An efficient design for a Socket server with buffer pool and a thread pool for concurrent request on the IOT platform is presented. This reduces the system overhead and buffer usage to the largest extent while faced with a large number of connections and digital requests. The simulation results show that a Socket server with a thread pool and buffer pool could lower the overhead on the context switch of threads as well as the I/O blocking.

关键词： Lakes

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Bacterial foraging optimization algorithm based routing strategy for wireless sensor networks

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International Review on Computers and Software 2012年第6期7卷 2826-2830页

作者： Chen, Zhi Li, Shuai Yue, Wenjing Hu, Luoquan Sun, Wanxin College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing 210003 China Suzhou Entry-Exit Inspection and Quarantine Bureau Suzhou 215104 China

In order to improve energy efficiency, the bacterial foraging optimization algorithm (OBFOA) is applied into the routing strategy for wireless sensor networks. The proposed strategy makes proper improvements on bacteria's foraging operation to improve the performance of the algorithm, such as the adaptive step strategy in the swimming operation and the comprehensive selection mechanism in the tumbling operation. OBFOA builds optimized data transfer paths in wireless sensor networks through the processes of chemotaxis, global quorum sensing mechanisms, reproduction and elimination-dispersal. Simulation results show that the proposed strategy can balance the energy consumption of nodes effectively and prolong the overall network lifetime. © 2012 Praise Worthy Prize S.r.l. - All rights reserved.

关键词： wireless sensor networks

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Packet sending algorithm based on bundle protocol in DTN networks

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Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and technology Edition) 2012年第SUPPL. 1期42卷 285-289页

作者： Wang, Kun Yu, Yue Zhang, Yu-Hua Guo, Huang Wang, Lin-Lin Key Lab. of Broadband Wireless Communication and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications Nanjing 210003 China

Bundle and block were introduced into DTN transmission protocol, which shred data into bits to deal with frequent interruption in DTN network. Bundle and LTP protocol in DTN transmission layer were put forward, and the impact of block size on transmission efficiency was investigated when network environment probably vary dramatically in a short time. Finally we put forward a Bundle sending algorithm that dynamically changes its strategy in DTN network to achieve the best transmission efficiency and system performance. Simulation results show that selecting proper size of data block can increase the transmission effectiveness.

关键词： Efficiency

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The Neighbors Selection Algorithm in WSN for routing and localization

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Journal of Information and Computational Science 2012年第4期9卷 1017-1025页

作者： Ma, Runze Yu, Zhijun Liu, Haitao Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Key Lab of Wireless Sensor Network and Communication Shanghai 200050 China Wuxi Sensing Net Industrialization Research Institute Wuxi Jiangsu 214135 China

There are some problems on the neighbor nodes selection method in wireless sensor networks. The Neighbors Selection Algorithm, based on the communication energy consumption between pairs of nodes, is proposed and applied to enhance the DV routing protocol and DV-Hop localization algorithm. According to the simulation results, in the networks where the node radio range is larger than the average distance between adjacent nodes, the modified routing method could cut down the routing energy consumption, and the modified localization algorithm could achieve better localization accuracy. Copyright © 2012 Binary Information Press.

关键词： Routing protocols

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Quality-delay tradeoff for video streaming over mobile ad hoc networks

Quality-delay tradeoff for video streaming over mobile ad ho...

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IEEE International Conference on communications (ICC)

作者： Liang Zhou Yan Zhang Joel Rodrigues Benoit Geller Jingwu Cui Baoyu Zheng Key Laboratory of Broadband Wireless Communication and Sensor Network Technology Ministry of Education Nanjing University of Posts and Telecommunications China Simula Research Laboratory Norway Instituto de Telecomunicaçőes University of Beira Interior Portugal Laboratory of UEI ENSTA Paristech France

In this work, we study the quality-delay tradeoff for video streaming over mobile ad hoc network by utilizing a class of scheduling schemes. We show that node spatial mobility indeed impacts on the performance of wireless video transmission under the assumption that all the nodes can identically and uniformly visit the entire network. To describe a practical mobile scenario, we consider a random walk mobility model in which each node can randomly and independently choose its mobility direction at each time-slot. The contributions of this work are twofold: 1) It investigates the optimal node velocity for the mobile video network which helps to identify the impact of mobility on the video performance; 2) It derives the achievable quality-delay tradeoff range for any node mobility velocity, and thus it is helpful to design appropriate quality and delay requirements. These results provide insights on network design and fundamental guidelines on establishing an efficient mobile wireless video transmission system.

关键词： Streaming media Delay Mobile ad hoc networks wireless communication Video recording Quality assessment

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Efficient two-step entanglement concentration for arbitrary W states

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Physical Review A 2012年第4期85卷 042302-042302页

作者： Yu-Bo Sheng Lan Zhou Sheng-Mei Zhao Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Telecommunications & Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We present two two-step practical entanglement concentration protocols for concentrating an arbitrary three-particle less-entangled W state into a maximally entangled W state assisted with single photons. The first protocol uses the linear optics and the second protocol adopts the cross–Kerr nonlinearity to perform the protocol. In the first protocol, based on the postselection principle, three parties say Alice, Bob, and Charlie in different distant locations can obtain the maximally entangled W state from the arbitrary less-entangled W state with a certain success probability. In the second protocol, the parties are not required to possess the sophisticated single-photon detectors and the concentrated photon pair can be retained after performing this protocol successfully. Moreover, the second protocol can be repeated to get a higher success probability. Both protocols may be useful in practical quantum-information applications.

关键词： Photons

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Efficient single-photon-assisted entanglement concentration for partially entangled photon pairs

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Physical Review A 2012年第1期85卷 012307-012307页

作者： Yu-Bo Sheng Lan Zhou Sheng-Mei Zhao Bao-Yu Zheng Institute of Signal Processing Transmission Nanjing University of Posts and Telecommunications Nanjing 210003 China College of Telecommunications & Information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China Key Lab of Broadband Wireless Communication and Sensor Network Technology Nanjing University of Posts and Telecommunications Ministry of Education Nanjing 210003 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We present two realistic entanglement concentration protocols (ECPs) for pure partially entangled photons. A partially entangled photon pair can be concentrated to a maximally entangled pair with only an ancillary single photon with a certain probability, while the conventional ECPs require two copies of partially entangled pairs at least. Our first protocol is implemented with linear optics and the second protocol is implemented with cross-Kerr-nonlinearities. Compared with other ECPs, they do not need to know the accurate coefficients of the initial state. With linear optics, it is feasible with current experiments. With cross-Kerr-nonlinearities, it does not require sophisticated single-photon detectors and can be repeated to get a higher success probability. Moreover, the second protocol can get the higher entanglement transformation efficiency and it may be the most economical protocol by far. Meanwhile, both protocols are more suitable for multiphoton system concentration because they need less operations and classical communications. All these advantages make the two protocols useful in current long-distance quantum communications.

关键词： QUANTUM entanglement NONLINEAR theories PROBABILITY theory MULTIPHOTON processes QUANTUM communication OPTICAL communications

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Green Multimedia communications over Internet of Things

Green Multimedia Communications over Internet of Things

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IEEE International Conference on communications

作者： Liang Zhou Min Chen Baoyu Zheng Jingwu Cui Key Lab of Broadband Wireless Communication and Sensor Network Technology (Nanjing University of Posts and Telecommunications) Ministry of Education School of Computer Science and Engineering Seoul National University

ISBN: (纸本)9781457720529

In this paper, we consider a power-aware multimedia communications over internet of things (IoT). Specifically, we consider a generic IoT scenario where a multimedia server provides heterogeneous applications without knowing the application's quality of experience (QoE) model and playout period. Our objective aims at dynamically adjusting the power allocation for each application over a uncertain period to maximize the system overall mean opinion score (MOS). Note that the practical QoE model can be observed over time, but the underlying functional relationship between the power and MOS is unknown. The highlight of this paper is to develop a dynamic powering algorithm, in which one learns the satisfaction function and optimizes power-aware user satisfaction with on-line operation. More precisely, the proposed algorithm performance is measured in terms of loss which denotes the MOS loss compared to the optimal one. Numerical simulation results validate the efficiency of the proposed algorithm.

关键词： Internet of things Green multimedia communications Dynamic powering QoE model

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