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A new algorithm based on the proximity principle for the virtual network embedding problem

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第12期14卷 908-908页

作者： jiang liu tao huang jian-ya chen yun-jie liu

The virtual network embedding/mapping problem is a core issue of network virtualization. It is concerned mainly with how to map virtual network requests to the substrate network efficiently. There are two steps in this problem： node mapping and link mapping. Current studies mainly focus on developing heuristic algorithms, since both steps are computationally intractable. In this paper, we propose a new algorithm based on the proximity principle, which considers the distance factor besides the capacity factor in the node mapping step. Thus, the two steps of the embedding problem can be better integrated and the substrate network resource can be used more efficiently. Simulation results show that the new algorithm greatly enhances the performance of the revenue/cost （R/C） ratio, acceptance ratio, and runtime of the embedding problem.

关键词：启发式算法虚拟网络嵌入问题映射问题网络嵌入距离因子网络资源仿真结果

Reverse-trace routing scheme in content centric networking

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 22-29页

作者： ZHANG yan huang tao liu jiang chen jian-ya liu yun-jie Key Laboratory of Universal Wireless Communications of Ministry of Education Beijing University of Posts and Telecommunications

Content center networking （CCN） is one of the most promising future network architectures. Current researches on CCN routing scheme mainly focus on finding the best single routing path, which may induce to low usage of the in-network caches. In order to overcome this problem, a reverse trace routing （RTR） scheme is proposed in this paper, in which Interest packet is sent to the edge-cache along with the reverse trace of the corresponding former Data packet. By doing this, the Interest packets will have better chances to be routed to the promising in-network caches before reaching the source server, which could increase the in-network hit rate, while decrease the server stress. The simulation results show clearly that the RTR scheme decreases the source server load, while reducing the mean hops of entire data retrieval process under certain circumstances.

关键词： CCN routing RTR next face table (NFT)

Fast convergence caching replacement algorithm based on dynamic classification for content-centric networks

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 45-50页

作者： FANG Chao huang tao liu jiang chen jian-ya liu yun-jie Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and Telecommunications

One of the key research fields of content-centric networking （CCN） is to develop more efficient cache replacement policies to improve the hit ratio of CCN in-network caching. However, most of existing cache strategies designed mainly based on the time or frequency of content access, can not properly deal with the problem of the dynamicity of content popularity in the network. In this paper, we propose a fast convergence caching replacement algorithm based on dynamic classification method for CCN, named as FCDC. It develops a dynamic classification method to reduce the time complexity of cache inquiry, which achieves a higher caching hit rate in comparison to random classification method under dynamic change of content popularity. Meanwhile, in order to relieve the influence brought about by dynamic content popularity, it designs a weighting function to speed up cache hit rate convergence in the CCN router. Experimental results show that the proposed scheme outperforms the replacement policies related to least recently used （LRU） and recent usage frequency （RUF） in cache hit rate and resiliency when content popularity in the network varies.

关键词： CCN cache replacement policy dynamic classification fast convergence category popularity

New algorithm for hub-and-spoke topological virtual networks embedding problem

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The Journal of China Universities of Posts and Telecommunications 2012年第1期19卷 55-61页

作者： liu jiang huang tao chen jian-ya liu yun-jie LÜ Bo Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

The virtual network embedding/mapping problem is a core issue of the network virtualization. It＇s mainly concerned with how to map virtual network requests to the substrate network efficiently. Previous researches mainly focus on developing heuristic algorithms for general topology virtual network request. In this paper, we propose a new algorithm for the hub-and-spoke （HAS） topology virtual request. The characters of the HAS topology are exploited to develop the new algorithm. The simulation results show that the new algorithm greatly enhances the performance of revenue/cost （R/C） ratio while the HAS topology request arrives.

关键词： virtual network embedding general topology HAS topology

Modeling in-network caching and bandwidth sharing performance in information-centric networking

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The Journal of China Universities of Posts and Telecommunications 2013年第2期20卷 99-105页

作者： WANG Guo-qing huang tao liu jiang chen jian-ya liu yun-jie Key Laboratory of Universal Wireless Communications of Ministry of Education Beijing University of Posts and Telecommunications School of Telecommunication Engineering Beijing University of Posts and Telecommunications

Information-centric networking （ICN） proposes a content-centric paradigm which has some attractive advantages, such as network load reduction, low dissemination latency, and energy efficiency. In this paper, based on the analytical model of ICN with receiver-driven transport protocol employing least-recently used （LRU） replacement policy, we derive expressions to compute the average content delivery time of the requests＇ arrival sequence of a single cache, and then we extend the expressions to a cascade of caches＇ scenario. From the expressions, we know the quantitative relationship among the delivery time, cache size and bandwidth. Our results, analyzing the trade-offs between performance and resources in ICN, can be used as a guide to design ICN and to evaluation its performance.

关键词： ICN LRU miss probability content delivery time

Design of in-network caching scheme in CCN based on grey relational analysis

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 1-8页

作者： CUI Xian-dong huang tao liu jiang LI Li chen jian-ya liu yun-jie State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Future Network Industry Innovation Center of China

In-network caching is one of the most important issues in content centric networking （CCN）, which may extremely influence the performance of the caching system. Although much work has been done for in-network caching scheme design in CCN, most of them have not addressed the multiple network attribute parameters jointly during caching algorithm design. Hence, to fill this gap, a new in-network caching based on grey relational analysis （GRA） is proposed. The authors firstly define two newly metric parameters named request influence degree （RID） and cache replacement rate, respectively. The RID indicates the importance of one node along the content delivery path from the view of the interest packets arriving The cache replacement rate is used to denote the caching load of the node. Then combining hops a request traveling from the users and the node traffic, four network attribute parameters are considered during the in-network caching algorithm design. Based on these four network parameters, a GRA based in-network caching algorithm is proposed, which can significantly improve the performance of CCN. Finally, extensive simulation based on ndnSIM is demonstrated that the GRA-based caching scheme can achieve the lower load in the source server and the less average hops than the existing the betweeness （Betw） scheme and the ALWAYS scheme.

关键词： CCN in-network caching request influence degree cache replacement rate grey relational analysis

Hierarchical network with diversified customer edge access

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 104-110,117页

作者： LI Rui huang tao chen jian-ya liu yun-jie Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China China Unicorn Beijing 100140 China

The Internet today originates from the advanced research project agency network （ARPANET） and evolves constantly during the past years. However, with incremental ＇patches＇ on the Internet, the current network architecture faces many problems which are too difficult to solve. In the light of recent interest in re-designing the Internet, the separation of core network and customer edge network, and the separation of identifier and locator receive wide consensus among scientists. We follow this direction and propose a new hierarchical network with diversified customer edge access （HNDCE） in this paper. We use switching addresses, routing addresses and identifiers to implement a true core/edge and locator/identifier split. In the core network, hierarchical switching addresses combined with tree topology makes routing replaced by switching. The Viliant load-balancing （VLB） structure is used here to compensate the topology＇s reliability and scalability. In the customer edge network, the split of locator and identifier makes it possible to deploy various routing schemes and new services. Hierarchical mapping system is also designed to support this new architecture.

关键词： hierarchical, identification, switching separation, VLB

Adaptive scheme based on status feedback for virtual network mapping

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The Journal of China Universities of Posts and Telecommunications 2011年第5期18卷 87-94页

作者： LU Bo huang tao WANG Zhen-kai chen jian-ya liu yun-jie liu jiang Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Network virtualization is considered as a powerful way to deploy different network architectures and protocols over a shared physical infrastructure. Virtual network （VN） embedding plays an important role in the network virtualization environment. Virtual network embedding is mainly about mapping virtual nodes and virtual links onto the physical network resources efficiently. However, load balancing of substrate network has not received much consideration. This paper proposes an adaptive virtual network mapping algorithm based on status feedback. The main contribution is to embed the virtual network requests according to the current load distribution of substrate network. This adaptive algorithm differentiates the residual bandwidth of substrate links and takes full advantage of the multi-path to improve the load balancing of the substrate network. Simulation experiments show that the proposed algorithm improves the load distribution of substrate network distinctly while reducing the average substrate link stress significantly.

关键词： network virtualization virtual network embedding load balancing

Searching for^(76)Ge neutrinoless double beta decay with the CDEX-1B experiment

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Chinese Physics C 2024年第10期48卷 11-22页

作者： Bing-tao Zhang Jun-Zheng Wang Li-tao yang Qian Yue Ke-Jun Kang Yuan-Jing Li Hai-Peng An C.Greeshma jian-Ping Chang yun-Huan chen jian-Ping cheng Wen-Han Dai Zhi Deng Chang-Hao Fang Xin-Ping Geng Hui Gong Qiu-Ju Guo Xu-Yuan Guo Li He Sheng-Ming He Jin-Wei Hu Han-Xiong huang Tu-chen huang Hai-tao Jia Xi jiang S.Karmakar Hao-Bin Li jian-Min Li Jin Li Qian-yun Li Ren-Ming-jie Li Xue-Qian Li Yu-Lan Li Yi-Fan Liang Bin Liao Fong-Kay Lin Shin-Ted Lin Jia-Xuan liu Shu-Kui liu yan-Dong liu Yu liu Yuan-Yuan liu Zhong-Zhi liu Hao Ma Yu-Cai Mao Qi-Yuan Nie Jin-Hua Ning Hui Pan Ning-Chun Qi jie Ren Xi-Chao Ruan Ze She Manoj Kumar Singh Tian-Xi Sun Chang-jian Tang Wei-You Tang yang Tian Guang-Fu Wang Li Wang Qing Wang Yu-Feng Wang yun-Xiang Wang Henry-Tsz-King Wong Shi-Yong Wu Yu-cheng Wu Hao-yang Xing Rui Xu Yin Xu tao Xue Yu-Lu yan Nan Yi Chun-Xu Yu Hai-Jun Yu jian-Feng Yue Ming Zeng Zhi Zeng Feng-Shou Zhang Lei Zhang Zhen-Hua Zhang Zhen-Yu Zhang Kang-Kang Zhao Ming-Gang Zhao Ji-Fang Zhou Zu-Ying Zhou Jing-Jun Zhou Key Laboratory of Particle and Radiation Imaging(Ministry of Education)and Department of Engineering Physics Tsinghua UniversityBeijing 100084 Department of Physics Tsinghua UniversityBeijing 100084 Institute of Physics Academia SinicaTaipei 11529 NUCTECH Company Beijing 100084 yaLong River Hydropower Development Company Chengdu 610051 College of Nuclear Science and Technology Beijing Normal UniversityBeijing 100875 College of Physics Sichuan UniversityChengdu 610065 School of Physics Peking UniversityBeijing 100871 Department of Nuclear Physics China Institute of Atomic EnergyBeijing 102413 Sino-French Institute of Nuclear and Technology Sun Yat-sen UniversityZhuhai 519082 School of Physics Nankai UniversityTianjin 300071 Department of Physics Banaras Hindu UniversityVaranasi 221005 Department of Physics Beijing Normal UniversityBeijing 100875

We operated a p-type point contact high purity germanium(PPCGe)detector(CDEX-1B,1.008 kg)in the China Jinping Underground Laboratory(CJPL)for 500.3 days to search for neutrinoless double beta(0νββ)decay of^(76)Ge.A total of 504.3 kg⋅day effective exposure data was *** anti-coincidence and the multi/single-site event(MSE/SSE)discrimination methods were used to suppress the background in the energy region of interest(ROI,1989–2089 keV for this work)with a factor of 23.A background level of 0.33 counts/(keV⋅kg⋅yr)was *** lower limit on the half life of^(76)Ge 0νββdecay was constrained as T_(1/2)^(0ν)>1.0×10^(23)yr(90%C.L.),corresponding to the upper limits on the effective Majorana neutrino mass:<3.2–7.5 eV.

关键词： neutrinoless double beta decay CDEX point-contact germanium detector ^(76)Ge