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Robust Virtual Network Embedding Based on Component Connectivity in Large-Scale Network

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China Communications 2017年第10期14卷 164-179页

作者： Xiaojuan Wang Mei Song Deyu Yuan Xiangru Liu Beijing university of posts and telecommunications Beijing 100876 China People's Public Security university of China Beijing China

Virtual network embedding problem which is NP-hard is a key issue for implementing software-defined network which is brought about by network virtualization. Compared with other studies which focus on designing heuristic algorithms to reduce the hardness of the NP-hard problem we propose a robust VNE algorithm based on component connectivity in large-scale network. We distinguish the different components and embed VN requests onto them respectively. And k-core is applied to identify different VN topologies so that the VN request can be embedded onto its corresponding component. On the other hand, load balancing is also considered in this paper. It could avoid blocked or bottlenecked area of substrate network. Simulation experiments show that compared with other algorithms in large-scale network, acceptance ratio, average revenue and robustness can be obviously improved by our algorithm and average cost can be reduced. It also shows the relationship between the component connectivity including giant component and small components and the performance metrics.

关键词： large-scale network component connectivity virtual network embedding SDN

Distributed GEP query optimization on grid service

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The Journal of China Universities of posts and telecommunications 2010年第3期17卷 118-122,128页

作者： DENG Yong, WANG Ru-chuan College of Computer, Nanjing university of posts and telecommunications, Nanjing 210003, China [a] College of Computer Nanjing University of Posts telecommunications Nanjing 210003 China

In order to better solve the problem of distributed query optimization, a query optimization algorithm on gene expression programming （GEP）（QO-GEP） is presented. On the basis of QO-GEP, distributed GEP query optimization on grid service （DGEPQO-GS） is proposed which combines grid service. Simulated experiments show that with the increment of the number of query relation, query time which QO-GEP carries out query decreases apparently. Meanwhile, with the increase of the number of grid nodes, the average querying success rate of DGEPQO-GS increases significantly.

关键词： gene expression programming distributed query grid service query relation

QoS routing based on mobile agent for LEO satellite IP networks

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The Journal of China Universities of posts and telecommunications 2009年第6期16卷 57-63页

作者： RAO Yuan,WANG Ru-chuan College of Computer,Nanjing university of posts and telecommunications,Nanjing 230001,China [a] College of Computer Nanjing university of posts and telecommunications Nanjing 230001 China

Current quality of service（QoS） routing schemes for low earth orbit（LEO） satellites IP networks either neglect the varying population density or fail to guarantee end-to-end *** a remedy,QoS routing protocol based on mobile agent（QoSRP-MA） is ***-MA is a source-based routing *** connection requests arrive,QoS mobile agents are dispatched from ingress satellite to explore routes,which migrate using satellite routing *** arriving in egress satellite,QoS mobile agents migrate back towards ingress satellite to reserve *** construct satellite routing tables,load balancing routing algorithm based on mobile agent（LBRA-MA） is *** LBRP-MA,at regular intervals mobile agents launched on all satellites migrate autonomously to evaluate path cost and update routing ***,path cost between source and destination is evaluated considering satellite geographical position as well as inter-satellite link（ISL） ***,ISL congestion index is considered to update routing *** simulations on a Courier-like constellation,it shows that QoSRP-MA can achieve guaranteed end-to-end delay bound with higher throughput,lower connection failing ratio and signaling overhead compared to high performance satellite routing（HPSR） scheme.

关键词： QoS routing load balancing mobile agent satellite IP networks

Structure splitting framework for data-layout optimization

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The Journal of China Universities of posts and telecommunications 2009年第5期16卷 107-113页

作者： FU Xiong , WANG Ru-chuan College of Computer, Nanjing university of posts and telecommunications, Nanjing 210003, China [a]College of Computer Nanjing university of posts and telecommunications Nanjing 210003 China

To improve data cache performance, optimizing program data layout by data reorganization has become an important method of decreasing the impact of increasing gap of speed between processor and memory. In this article, a structure splitting framework with an analysis model named structure field relation graph （SFRG） is presented to optimize program data layout. The SFRG can be used to quantify relationship between fields. It helps to find an optimal layout for structure as well as the optimal program data layout. And the data cache performance is improved through SFRG-based structure splitting. Experiments show that this framework is effective in optimizing program data layout and improving the performance of data cache and whole program.

关键词： program optimization structure splitting data layout cache performance

STABILITY OF GENERALIZED JACKSON NETWORKS WITH INFINITE SUPPLY OF WORK

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Journal of Systems Science & Complexity 2008年第2期21卷 283-295页

作者： Yongjiang GUO School of Science Beijing University of Posts and Telecommunications Beijing 100876 China

A general Jackson network （GJN） with infinite supply of work is considered. By fluid limit model, the author finds that the Markov process describing the dynamics of the GJN with infinite supply of work is positive Harris recurrent if the corresponding fluid model is stable. Furthermore, the author proves that the fluid model is stable if the usual traffic condition holds.

关键词： Fluid limit model general Jackson network (GJN) infinite supply positive Harris recurrent stability.

SVM-based loss differentiation algorithm for wired-cum-wireless networks

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The Journal of China Universities of posts and telecommunications 2009年第4期16卷 104-111页

作者： DENG Qian-hua ,CAI An-ni School of Telecommunication Engineering,Beijing university of posts and telecommunications,Beijing 100876,China [a]School of Telecommunication Engineering Beijing university of posts and telecommunications Beijing 100876 China

In a hybrid wired-cum-wireless network environment, packet loss may happen because of congestion or wireless link errors. Therefore, differentiating the cause is important for helping transport protocols take actions to control congestion only when the loss is caused by congestion. In this article, an end-to-end loss differentiation mechanism is proposed to improve the transmission performance of transmission control protocol （TCP）-friendly rate control （TFRC） protocol. Its key design is the introduction of the outstanding machine learning algorithm - the support vector machine （SVM） into the network domain to perform multi-metric joint loss differentiation. The SVM is characterized by using end-to-end indicators for input, such as the relative one-way trip time and the inter-arrival time of packets fore-and-aft the loss, while requiring no support from intermediate network apparatus. Simulations are carried out to evaluate the loss differentiation algorithm with various network configurations, such as with different competing flows, wireless loss rate and queue size. The results show that the proposed classifier is effective under most scenarios, and that its performance is superior to the ZigZag, mBiaz and spike （ZBS） scheme.

关键词： machine learning SVM TCP-friendly rate control (TFRC) congestion control

Digital Rights Management：Model,Technology and Application

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China Communications 2017年第6期14卷 156-167页

作者： Zhaofeng Ma School of Cyberspace Security Beijing University of Posts and Telecommunications Beijing 100876 China

with rapid achievement of current information technology and computing ability and applications,much more digital content such as films,cartoons,design drawings,office documents and software source codes are produced in daily work,however to protect the content being copying,shared or deliberately stolen by inside or outside,digital rights management(DRM) became more and more important for digital content *** this paper,we studied various DRM model,technology and application,and first proposed DRM Security Infrastructure(DSI),in which we defined encryption,hash,signature algorithm,watermarking algorithms,authentication,usage control,trusted counter,conditional trace,secure payment,and based on the DSI we then proposed a whole classification approach and architecture of all kinds of DRMs,in which we proposed 6 typical classes of copyrights and content protection DRMs architecture:(1) Software-oriented DRM,(2) e Book-oriented DRM,(3) Video-oriented DRM,(4) Image-Oriented DRM(5) Unstructured data oriented DRM,(6) Text-oriented *** on the above DSI,we then proposed a dynamic DRM model selection method for various DRM application,which can be adapted dynamically for different technology of different applications,which can provide awhole solution for variant DRM development in a rapid and customized *** proposed DRM method,technology and application in this paper provided a common,flexible and extendable solution for variant DRM scenes,and can support rapid and customized ***,we proposed an opinion that the future life will enter into a new era that the content usage and consumption will not again adopt DRM technology rather than with law,liberty and morality.

关键词： digital rights management drm security infrastructure encryption watermark usage control drm-free

Secure coverage-preserving node scheduling scheme using energy prediction for wireless sensor networks

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The Journal of China Universities of posts and telecommunications 2010年第5期17卷 100-108页

作者： LI Zhi-yuan,WANG Ru-chuan. College of Computer,Nanjing university of posts and telecommunications,Nanjing 210003,China [a] College of Computer Nanjing University of Posts telecommunications Nanjing 210003 China

With the fast development of the micro-electro-mechanical systems （MEMS）,wireless sensor networks （WSNs） have been extensively *** of the studies focus on saving energy consumption because of restricted energy supply in ***-based node scheduling scheme is commonly considered as one of the most energy-efficient ***,it is not always so efficient especially when there exist hot spot and network attacks in *** this article,a secure coverage-preserved node scheduling scheme for WSNs based on energy prediction is proposed in an uneven deployment *** scheme is comprised of an uneven clustering algorithm based on arithmetic progression,a cover set partition algorithm based on trust and a node scheduling algorithm based on energy *** results show that network lifetime of the scheme is 350 rounds longer than that of other scheduling ***,the scheme can keep a high network coverage ratio during the network lifetime and achieve the designed objective which makes energy dissipation of most nodes in WSNs balanced.

关键词： wireless sensor networks secure energy-efficient coverage node scheduling cover set energy prediction

Search recommendation model based on user search behavior and gradual forgetting collaborative filtering strategy

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The Journal of China Universities of posts and telecommunications 2010年第3期17卷 110-117页

作者： LIU Chuan-chang State Key Laboratory of Networking and Switching Technology, Beijing university of posts and telecommunications, Beijing 100876, China [a] State Key Laboratory of Networking Switching Technology Beijing University of Posts telecommunications Beijing 100876 China

The existing search engines are lack of the consideration of personalization and display the same search results for different users despite their differences in interesting and purpose. By analyzing user＇s dynamic search behavior, the paper introduces a new method of using a keyword query graph to express user＇s dynamic search behavior, and uses Bayesian network to construct the prior probability of keyword selection and the migration probability between keywords for each user. To reflect the dynamic changes of the user＇s preference, the paper introduces non-lineal gradual forgetting collaborative filtering strategy into the personalized search recommendation model. By calculating the similarity between each two users, the model can do the recommendation based on neighbors and be used to construct the personalized search engine.

关键词： search recommendation model search behavior expression keyword query graph gradual forgetting collaborative filtering