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Effective solutions to a global 3D visual system in networking environments

第一届中国高校通信类院系学术研讨会

作者： Li Ji Hu Ying Zheng Kangfeng Xiu Xinxin Yang Yixian Information security center,state key laboratory of networking and switching technology,beijing university of posts and Telecommunications,beijing 100876

＜正＞As a new kind of DDoS attack method,DRDoS （Distributed Reflect Denial of Service）is easy to launch, but difficult to trace back and *** this paper,the identical properties and possible scenes of DRDoS are discussed,and a novel DRDoS attack model based on magnification factor and diffusion factor is *** the same time,a traffic equation based on the magnification factor and diffusion factor is presented,and the influence of magnification effect and diffusion effect to defend methods are analyzed.

关键词： Network Security Ddos Attack Reflect Attack

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Science china Earth Sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2, ZHANG Yan3, YANG Chongjun2, LIU Suhong1, REN Yingchao2, RUI Xiaoping2 & LIU Donglin2 1. state key laboratory of Remote Sensing Sciences, School of Geography and Remote Sensing, beijing Normal university, beijing 100875, china 2. state key laboratory of Remote Sensing Sciences, Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 101001, china 3. Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 101001, china 1. state key laboratory of Remote Sensing Sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. Chinese Academy of Sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3D visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

Construction of Convolutional Network Coding for Cyclic Multicast Networks

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Construction of Convolutional Network Coding for Cyclic Mult...

INTEGRATION OF OPTICAL AND WIRELESS NETWORKS

2010 IEEE 2nd Symposium on Web Society

作者： Qin Guo~(1,2,3),Mingxing Luo~(1,2,3),Lixiang Li~(1,2,3),Licheng Wang~(1,2,3),Yixian Yang~(1,2,3) 1 Information Security Center,state key laboratory of networking and switching technology, beijing university of posts and Telecommunications,beijing 100876,china 2 key laboratory of Network and Information Attack and Defence technology of MOE, beijing university of posts and Telecommunications,beijing 100876,china 3 National Engineering laboratory for Disaster Backup and Recovery, beijing university of posts and Telecommunications,beijing 100876,china.

＜正＞In this paper,we present a practical algorithm to construct the convolutional multicast network coding over any finite directed cyclic *** dual line graph of a directed cyclic graph is considered as a *** regarding the global encoding kernels in the original graph as the corresponding inputs or outputs of some subsystem and the local encoding kernels in original graph as gains of channels,we can construct the convolutional network code through randomly choosing the local encoding kernels of the directed cycles in *** using Mason formula,the construction becomes very efficient.

关键词： Convolutional network code convolutional multicast dual line graph Mason formula

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china communications 2014年第5期11卷 I0001-I0002页

作者：徐坤祝宁华 Hussein Mouftah the state key laboratory of Information Photonics and Optical communications at Beijing University of Posts and Telecommunications Department of Electrical and Computer Engineering University of Ottawa

For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth *** fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and ***,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated *** provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network

关键词：无线网络集成光学无线系统网络工程无线技术光纤

A LIMITED RESOURCE VECTOR LOAD-BALANCING ALGORITHM FOR SOFTSWITCH-BASED HETEROGENEOUS CLUSTERED MEDIA SERVER

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Journal of Electronics(china) 2006年第5期23卷 683-690页

作者： Wu Naixing Liao Jianxin Zhu Xiaomin state key Lab of networking and switching Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the system feature of softswitch-based heterogeneous clustered media server, this paper proposed a limited resource vector load-balancing algorithm. The purpose of the algorithm was to balance the load of clusters by utilizing all system resources effectively and to avoid violent shaking of the system per- formance. A lot of simulations on the Petri net model of load balance system are conducted and the algorithm is compared with some traditional algorithms on balancing ability for heterogeneity, system throughput, re- quest response time and performance stability. The results of simulations show that the algorithm achieves system higher performance and it has excellent ability to deal with the heterogeneity of clustered media server.

关键词： Load-balancing algorithm Heterogeneous cluster Media server Softswitch SPN (Stochastic Petri Net)

A NEW DYNAMIC QUOTA-BASED ADMISSION CONTROL WITH SUB-NEGOTIATION FOR SOFTSWITCH-BASED CLUSTERED MEDIA SERVER

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Journal of Electronics(china) 2006年第5期23卷 675-682页

作者： Wu Naixing Liao Jianxin Zhu Xiaomin state key Lab of networking and switching Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the demand of the admission control of softswitch-based clustered media server, this pa- per proposed a new dynamic quota-based admission control algorithm that has a sub-negotiation process. The strongpoint of quota-based algorithm had been inherited in the algorithm and at the same time some new ideas had also been introduced into it. Simulations of the algorithm had been conducted on the Petri net model and the results show that this algorithm has excellent performance. In order to find the optimal resource quota set- ting in real time, the paper proposed two approximation analysis methods. It can be seen from analysis results that these two methods can be used to get sub-optimal quota values quickly and effectively. These two ap- proximation analysis methods will play important roles in implementation of the algorithm in system.

关键词： Admission control algorithm Clustered media server NGN (Next Generation Network) Stochastic Petri net

G-MER： Green Mobility Estimation- Based Routing Protocol in Wireless Sensor Network

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china communications 2012年第5期9卷 10-21页

作者： Quan Wei Guan Jianfeng Xu Changqiao Zhang Hongke beijing Univ posts & Telecommun State Key Lab Networking & Switching Technol Beijing 100876 Peoples R China beijing Univ posts & Telecommun Inst Sensing Technol & Business Wuxi 214028 Peoples R China beijing Jiaotong Univ Natl Engn Lab Next Generat Internet Interconnect Beijing 100044 Peoples R China

As a core technology of Intemet of Things （loT）, Wireless Sensor Network （WSN） has become a research hotspot recently. More and more WSNs are being deployed in highly mobile environments. The fast moving sensor nodes bring significant challenges for the routing decision. In this paper, we propose an efficient logical location method, and designe a mobility estimating metric and derive a novel Green Mobility Estirmtion- based Routing protocol （G-MER） for WSNs. We also set up a full framework to evaluate its per- formance. Simulation results illustrate that G-MER achieves a fairly better perforrmnce in terrm of broadcast times and link failures than AODV. What＇s more, it decreases the mean hops by about 0.25 and reduces energy consumption by about 10% during the whole experiment. All the results show that G-MER can be effectively used in fast- moving and limited resource scenarios.

关键词： IoT WSN green routing protocol rmbility estimation dynamic window energy con-suming model

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IN/CORBA网关中的协议映射研究

计算机工程与应用 2003年第31期39卷 11-13,40页

作者：胡晓娟苏森北京邮电大学程控交换技术与通信网国家重点实验室北京100876

文章首先对CORBA(CommonObjectRequestBrokerArchitecture)平台上分布式智能网IN(IntelligentNet-work)的基本体系结构及IN/CORBA网关在此体系结构中的位置及作用进行了介绍,之后在此基础上着重研究了IN/CORBA协作网关中协议映射的有关... 详细信息

关键词：智能网协议映射CORBA INAP IDL ASN.1

Comparison of the compensation effects of fiber nonlinear impairments with mid-span optical phase conjugation between PDM CO-OFDM system and PDM QPSK system

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Chinese Physics B 2016年第8期25卷 191-195页

作者：徐菲郭梦琪王蕾乔耀军田慧平 state key laboratory of Information Photonics and Optical communications beijing university of posts and Telecommunications Beijing 100876 China

The compensation effects of fiber nonlinearity in 112 Gb/s polarization division multiplexing（PDM） coherent optical systems by mid-span optical phase conjugation（OPC） based on four wave mixing（FWM） effect are studied. Comparisons of the compensation results between PDM coherent optical-orthogonal frequency division multiplexing（CO-OFDM）system and the single carrier（SC） PDM quadrature phase shift keying（QPSK） system are provided as well. The results demonstrate that nonlinear compensation effect with mid-span OPC in PDM CO-OFDM system is much more obvious than that in SC PDM QPSK system.

关键词： nonlinear compensation mid-span OPC PDM CO-OFDM QPSK