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A Distributed and Adaptive Location Management Scheme for Hierarchical Mobility Management

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The Journal of China Universities of Posts and Telecommunications 2006年第1期13卷 34-39页

作者： HU Xiao song jun-de song Mei ZHOU Wei School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

Hierarchical mobility management is sensitive to the failure of gateway mobility agents and prone to degrade performance on heavy loads. This paper proposes a distributed and adaptive location management scheme based on Hierarchical Mobile IPv6. This scheme can balance the loads of mobility anchor points and increase the robustness of the hierarchical structure to certain extents. In this scheme, the optimized IP paging scheme is adopted to reduce the paging signaling cost and improve the scalability of the hierarchical mobility management. We implement the distributed and adaptive location management scheme in a simulation platform and compare its performance with that of two other location management schemes. Our simulation results show that our scheme is capable of balancing the signaling and traffic loads of mobility ancher points, decreasing the average handover latency, and increasing the throughout of the visited networks.

关键词： HMM location management location update IP Paging distributed

A distributed location management strategy for next- generation IP-based wireless networks

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The Journal of China Universities of Posts and Telecommunications 2006年第3期13卷 38-42页

作者： song Mei FENG Rui-jun HUANG Jian-wen song jun-de PCN and CAD Center School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Location management is the most important function in mobility management technology. The hierarchical structure of the proposed hierarchical network-layer mobility management （HNMM） can reduce the signaling cost. The selforganizing topology scheme can enhance the robustness and quality of the mobility management. The information of location of the mobile node is stored in the distributed database, which makes the storage of the location information more reliable and robust, and more flexible strategies can be used. The numeric results show that HNMM can provide better performance than the general structure of mobile IPv6, when the mobile nodes move frequently and when there is high traffic throughput.

关键词： location management mobile IPv6 mobility management IP-based wireless networks

Quantitative and qualitative research on service quality evaluation system in NGN

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 71-77页

作者： LIU Lu ZHOU Wen-an song jun-de ICT and SSME Center Beijing University of Posts and Telecommunications Beijing 100876 China

With the development of next generation network （NGN）, reasonable service quality evaluation is essential in network management. Based on NGN service characteristics, this article presents a comprehensive service quality evaluation system from two perspectives： quantitative and qualitative. From the quantitative point of view, this article brings forward the normalized service level achievement function （NSLA function） at technical layer. Also, with mean opinion score （MOS） mode, it proposes customer satisfaction assessment methods at customer perception layer. From the qualitative perspective, a hierarchical model is established, which forms mapping relations from the upper customer perception to the lower service quality parameters, and then the influence of different service parameters on customer satisfaction degree can b＇e denoted by the fuzzy analysis hierarchy process （FAHP） algorithm. Quantitative and qualitative evaluations together form a comprehensive solution which is universal, customer-oriented and flexible. demonstrated by the representative voice service, the proposed system is proved reliable and applicable to service evaluation in NGN.

关键词： customer satisfaction degree key quality indicator (KQI) NSLA function quality of experience index (QoE index) FAHP

Enhanced performance based on cross-layer design from physical to transport layers for multihop wireless networks

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The Journal of China Universities of Posts and Telecommunications 2010年第5期17卷 87-92页

作者： CHEN Guang-quan song Mei ZHANG Yong song jun-de School of Computer Science and Technology Beijing University of Posts and Telecommunications Beijing 100876 China School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This paper puts forward a novel cognitive cross-layer design algorithms for multihop wireless networks optimization across physical,mediam access control （MAC）,network and transport *** is well known,the conventional layered-protocol architecture can not provide optimal performance for wireless networks,and cross-layer design is becoming increasingly important for improving the performance of wireless *** this study,we formulate a specific network utility maximization （NUM） problem that we believe is appropriate for multihop wireless *** using the dual algorithm,the NUM problem has been optimal decomposed and solved with a novel distributed cross-layer design algorithm from physical to transport *** solution enjoys the benefits of cross-layer optimization while maintaining the simplicity and modularity of the traditional layered *** proposed cross-layer design can guarantee the end-to-end goals of data flows while fully utilizing network *** simulations have evaluated an enhanced performance of the proposed algorithm at both average source rate and network ***,the proposed algorithm has low implementation complexity for practical reality.

关键词： multihop wireless networks cross-layer design optimization distributed algorithm

OFDM frame synchronization based on energy difference of the received preamble

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 96-99页

作者： JIANG Feng song Mei GUO Da song jun-de CAD and PCN Center Electronic Engineering Institute Beijing University of Posts and Telecommunications Beijing 100876 China

The article presents a novel orthogonal frequency division multiplexing （OFDM） frame synchronization method. The method uses the preamble that contains two identical halves, and the energy difference of the two similar parts of the received preamble in receiver is used to obtain the frame＇s correct starting point. Furthermore, an improvement of the proposed method is presented, which uses the preamble that can be divided into four similar portions, and the energy difference of the four similar parts of the received preamble in receiver is used to obtain the frame＇s correct starting point. The performances of the frame synchronization methods in multipath channel are compared in terms of mean square error （MSE） obtained by simulations. It can be seen from the simulation results that the proposed methods have better performances than Schmidl＇s, Minn＇s, and Park＇s method in multipath channel.

关键词： orthogonal frequency division multiplexing (OFDM)timing offset frame synchronization

High throughput route selection in multi-rate wireless mesh networks

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 13-18页

作者： WEI Yi-fei GUO Xiang-li song Mei song jun-de Personal Communication Networks Computer Aided design Center School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Most existing Ad-hoc routing protocols use the shortest path algorithm with a hop count metric to select paths. It is appropriate in single-rate wireless networks, but has a tendency to select paths containing long-distance links that have low data rates and reduced reliability in multi-rate networks. This article introduces a high throughput routing algorithm utilizing the multi-rate capability and some mesh characteristics in wireless fidelity （WiFi） mesh networks. It uses the medium access control （MAC） transmission time as the routing metric, which is estimated by the information passed up from the physical layer. When the proposed algorithm is adopted, the Ad-hoc on-demand distance vector （AODV） routing can be improved as high throughput AODV （HT-AODV）. Simulation results show that HT-AODV is capable of establishing a route that has high data-rate, short end-to-end delay and great network throughput.

关键词： wireless mesh networks Ad-hoc AODV routing protocol multi-rate WiFi

New formulae for Tate pairing computation on Weierstrass curves

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 85-89页

作者： WANG Hong WANG Kun-peng song jun-de School of Information and Communication Engineering Beijing University of Posts and Telecommunications Venustech Cybervision Co. Ltd. Zhong Guancun Science Park Haidian Enterprises Postdoctoral Workstation Institute of Information Engineering University of Chinese Academy of Sciences

This paper proposes a variation of Miller＇s algorithm for Tate pairing computation on Weierstrass curves. Unlike the original Miller＇s algorithm which consists of two major operations： the doubling operation and the addition operation, this new algorithm replaces the addition with a doubling-addition （DA） operation to take the advantage of the fast point doubling-addition formula. Explicit formulae are given for the new algorithm. We suggest to use the new formulae for Weierstrass curves with general parameters for Tate pairing to gain a better performance.

关键词： elliptic curve Weierstrass Trate pairing Miller function

Research and design of wap service system based on MISC platform

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The Journal of China Universities of Posts and Telecommunications 2006年第4期13卷 34-38页

作者： YU Oun song Mei-na song jun-de ZHAN Xiao-su PCN and CAD Center Beijing University of Posts and Telecommunications Beijing 100876 China

Wireless application protocol （WAP） have become the available method for subscribers to access mobile Internet through mobile terminal, regardless of the location and time. In this article, a logical architecture of WAP service system based on mobile information service centre （MISC） [1, 2] platform is discussed. The whole system is designed and developed on Java 2 enterprise edition [3] （J2EE） architecture and deployed on BEA WebLogic Server [3, 4]. Furthermore, a series of various WAP services based on this system have been implemented, which validates the practice value of this system. This optimal scheme presented in this article will reduce the development complexity, deployment risk, and so on.

关键词： WAP MISC J2EE WAP Engine MBlog

Research on intelligent fault diagnosis based on time series analysis algorithm

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The Journal of China Universities of Posts and Telecommunications 2008年第1期15卷 68-74页

作者： CHEN Gang LIU Yang ZHOU Wen-an song jun-de School of Electronic Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

Aiming to realize fast and accurate fault diagnosis in complex network environment, this article proposes a set of anomaly detection algorithm and intelligent fault diagnosis model. Firstly, a novel anomaly detection algorithm based on time series analysis is put forward to improve the generalized likelihood ratio （GLR） test, and thus, detection accuracy is enhanced and the algorithm complexity is reduced. Secondly, the intelligent fault diagnosis model is established by introducing neural network technology, and thereby, the anomaly information of each node in end-to-end network is integrated and processed in parallel to intelligently diagnose the fault cause. Finally, server backup solution in enterprise information network is taken as the simulation scenario. The results demonstrate that the proposed method can not only detect fault occurrence in time, but can also implement online diagnosis for fault cause, and thus, real-time and intelligent fault management process is achieved.

关键词： network management fault diagnosis time series analysis neural network