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Topology awareness algorithm for virtual network mapping

Journal of Zhejiang University-Science C(computers and Electronics) 2012年第3期13卷 178-186页

作者： Xiao-ling LI Huai-min WANG Chang-guo GUO Bo DING Xiao-yong LI Wen-qi BI Shuang TAN National Key Laboratory of Parallel and Distributed Processing National University of Defense Technology.Changsha 410073China School of Computer National University of Defense TechnologyChangsha 410073China China Electronic Systems Engineering Corporation Beijing 100039China The Northern Institute of Electronic Equipment of China Beijing 100083China

Network virtualization is recognized as an effective way to overcome the ossification of the Internet. However, the virtual network mapping problem (VNMP) is a critical challenge, focusing on how to map the virtual networks to the substrate network with efficient utilization of infrastructure resources. The problem can be divided into two phases: node mapping phase and link mapping phase. In the node mapping phase, the existing algorithms usually map those virtual nodes with a complete greedy strategy, without considering the topology among these virtual nodes, resulting in too long substrate paths (with multiple hops). Addressing this problem, we propose a topology awareness mapping algorithm, which considers the topology among these virtual nodes. In the link mapping phase, the new algorithm adopts the k-shortest path algorithm. Simulation results show that the new algorithm greatly increases the long-term average revenue, the acceptance ratio, and the long-term revenue-to-cost ratio (R/C).

关键词： Network virtualization Ossification Virtual network （VN） mapping Substrate network （SN） Topology awareness Acceptance ratio

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An irregular cutting based distributed mapping algorithm for DVE systems

An irregular cutting based distributed mapping algorithm for...

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2009 2nd Asia-Pacific Conference on Computational Intelligence and Industrial Applications, PACIIA 2009

作者： Zhang, Wei Zhou, Hangjun Peng, Yuxing Li, Sikun Xi, Min National Laboratory for Parallel and Distributed Processing School of Computer Science National University of Defense Technology Changsha 410073 China Department of Computer Science Xi'an Jiaotong University Xi'an 710049 China

ISBN: (纸本)9781424446070

distributed Virtual Environment (DVE) systems have become more and more important both in academic communities and the industries. To guarantee the load constrain, the physical world integrity and the virtual world integrity, the virtual environment should be divided into several parts and mapped to multiple servers, which are located in geographically different places. Many centralized algorithms based on regular cutting method are proposed to solve this problem. However, the dynamic property of clients and distributed property of the system make the existing algorithms unable to undertake it. In this paper, we propose a metric to measure the cutting quality and design a distributed mapping algorithm based on an irregular cutting. Simulation results show that our algorithm greatly decreases the costs of DVE systems for migration of clients and effectively improves the satisfaction degree of users. ©2009 IEEE.

关键词： Virtual reality

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Reducing repair traffic in P2P backup systems: Exact regenerating codes on hierarchical codes

Reducing repair traffic in P2P backup systems: Exact regener...

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作者： Huang, Zhen Biersack, Ernst Peng, Yuxing Department of Computer National Laboratory of Parallel and Distributed Processing National University of Defense Technology Changsha Hunan 410073 China Eurecom Sophia Antipolis France

Peer to peer backup systems store data on "unreliable" peers that can leave the system at any moment. In this case, the only way to assure durability of the data is to add redundancy using either replication or erasure codes. Erasure codes are able to provide the same reliability as replication requiring much less storage space. Erasure coding breaks the data into blocks that are encoded and then stored on different nodes. However, when storage nodes permanently abandon the system, new redundant blocks must be created, which is referred to as repair. For "classical" erasure codes, generating a new block requires the transmission of k blocks over the network, resulting in a high repair traffic. Recently, two new classes of erasure codes, Regenerating Codes and Hierarchical Codes, have been proposed that significantly reduce the repair traffic. Regenerating Codes reduce the amount of data uploaded by each peer involved in the repair, while Hierarchical Codes reduce the number of nodes participating in the repair. In this article we propose to combine these two codes to devise a new class of erasure codes called ER-Hierarchical Codes that combine the advantages of both. © 2011 ACM.

关键词： Repair

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RScam: Cloud-based anti-malware via reversible sketch 11th

RScam: Cloud-based anti-malware via reversible sketch

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11th International Conference Security and Privacy in Communication Networks, SecureComm 2015

作者： Sun, Hao Wang, Xiaofeng Su, Jinshu Chen, Peixin College of Computer National University of Defense Technology Changsha China National Key Laboratory for Parallel and Distributed Processing National University of Defense Technology Changsha China

ISBN: (纸本)9783319288642

Cybercrime caused by malware becomes a persistent and damaging threat which makes the trusted security solution urgently demanded, especially for resource-constrained ends. The existing industry and academic approaches provide available anti-malware systems based on different perspectives. However, it is hard to achieve high performance detection and data privacy protection simultaneously. This paper proposes a cloud-based anti-malware system, called RScam, which provides fast and trusted security service for the resource-constrained ends. In RScam, we present suspicious bucket filtering, a novel signature-based detection mechanism based on the reversible sketch structure, which provides retrospective and accurate orientations of malicious signature fragments. Then we design a lightweight client which utilizes the digest of signature fragments to sharply reduce detection range. Finally, we design balanced interaction mechanism, which transmits sketch coordinates of suspicious file fragments and transformation of malicious signature fragments between the client and cloud server to protect data privacy and reduce traffic volume. We evaluate the performance of RScam with campus suspicious traffic and normal files. The results demonstrate validity and veracity of the proposed mechanism. Our system can outperform other existing systems with less time and traffic consumption. © Institute for computer Sciences, Social Informatics and Telecommunications Engineering 2015.

关键词： Malware

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MilKBQA: A Complex Knowledge Base Question Answering Dataset on Chinese Military Field 6

MilKBQA: A Complex Knowledge Base Question Answering Dataset...

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6th IEEE International Conference on Data Science in Cyberspace, DSC 2021

作者： Xu, Pike Li, Tiejun Huang, Zhen Guo, Min He, Jiezhong Sun, Ding Institute Of Computer National University Of Defense Technology Changsha China National University Of Defense Technology Laboratory Of Parallel And Distributed Processing Changsha China School Of Computer National University Of Defense Technology Changsha China

ISBN: (纸本)9781665418157

Facts in military field tend to involve elements of time, space, quantity, status, and so on. Existing methods of representing knowledge in the form of triples fail to adequately express these facts, and also cause obstacles to knowledge storage and updating. Furthermore, question answering on these facts introduces new complexity dimension, which are complicated to be supported by existing corpus. Thus, we construct a Chinese knowledge base for military field covering entities and events centric knowledge, referred as MilKB. It consists of 965 entities and 3,017 facts. Moreover, we classify the natural questions into 26 types and construct a complex question answering dataset derived from MilKB, referred as MilKBQA. It consists of 2,829 question-answer pairs, in which 600 are event-centric ones. Experiments with three recent strong baseline models demonstrate that MilKBQA requires further research. © 2021 IEEE.

关键词： Knowledge based systems

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CloudDPI: Cloud-based privacy-preserving deep packet inspection via reversible sketch 1

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9th International Symposium on Cyberspace Safety and Security, CSS 2017

作者： Li, Jie Su, Jinshu Wang, Xiaofeng Sun, Hao Chen, Shuhui School of Computer National University of Defense Technology Changsha Hunan410073 China National Key Laboratory for Parallel and Distributed Processing National University of Defense Technology Changsha Hunan410073 China

ISBN: (数字)9783319694719

ISBN: (纸本)9783319694702

Hardware-based middleboxes are ubiquitous in computer networks, which usually incur high deployment and management expenses. A recently arsing trend aims to address those problems by outsourcing the functions of traditional hardware-based middleboxes to high volume servers in a cloud. This technology is promising but still faces a few challenges. First, the widely adopted data encryption techniques contradict with payload inspection needs of some middleboxes such as DPI and IDS devices. Second, the inspection rules of middleboxes may be commercial properties, thus the middlebox providers want to keep their rules confidential under third-party cloud environments, and this creates hindrances for the cloud to perform outsourced middlebox functions. Third, performance of the outsourced middlebox is an inevitable issue that needs deliberate consideration. In this paper, we propose a cloud-based DPI middlebox implementation which performs payload inspection over encrypted traffic while preserving the privacy of both communication data and inspection rules. Our design employs a modified reversible sketch structure which is used for efficient error-free membership testing, and we utilize unkeyed one-way hash functions instead of complex cryptographic protocols to achieve the privacy preservation requirements. CloudDPI supports a wide range of real-world inspection rules, we conduct evaluations on ClamAV rule set and the experiment results demonstrate the effectiveness of our proposal. © 2017, Springer International Publishing AG.

关键词： Network function virtualization

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Character feature learning for named entity recognition

Character feature learning for named entity recognition

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作者： Zeng, Ping Tan, Qingping Zhang, Haoyu Meng, Xiankai Zhang, Zhuo Xu, Jianjun Lei, Yan College of Computer National University of Defense Technology Changsha China National Key Laboratory for Parallel and Distributed Processing Changsha China School of Software Engineering Chongqing University Chongqing China

The deep neural named entity recognition model automatically learns and extracts the features of entities and solves the problem of the traditional model relying heavily on complex feature engineering and obscure professional knowledge. This issue has become a hot topic in recent years. Existing deep neural models only involve simple character learning and extraction methods, which limit their capability. To further explore the performance of deep neural models, we propose two character feature learning models based on convolution neural network and long short-term memory network. These two models consider the local semantic and position features of word characters. Experiments conducted on the CoNLL-2003 dataset show that the proposed models outperform traditional ones and demonstrate excellent performance. © Copyright 2018 The Institute of Electronics Information and Communication Engineers.

关键词： Extraction

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Tree-structured bloom filters for joint optimization of false positive probability and transmission bandwidth

Tree-structured bloom filters for joint optimization of fals...

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ACM SIGMETRICS International Conference on Measurement and Modeling of computer Systems, SIGMETRICS 2015

作者： Fu, Yongquan Biersack, Ernst Science and Technology Laboratory of Parallel and Distributed Processing School of Computer National Univ. of Defense Technology China Www.e-biersack.eu France

ISBN: (纸本)9781450334860

Bloom filters are frequently used to perform set queries that test the existence of some items. However, Bloom filters face a dilemma: the transmission bandwidth and the accuracy cannot be optimized simultaneously. This dilemma is particularly severe for transmitting Bloom filters to remote nodes when the network bandwidth is limited. We propose a novel Bloom filter BloomTree that consists of a tree-structured organization of smaller Bloom filters, each one using a set of independent hash functions. BloomTree spreads items across levels that are compressed to reduce the transmission bandwidth need. We investigate in detail under which conditions BloomTree performs better than the compressed Bloom filter and the standard Bloom filter. © Copyright 2015 ACM.

关键词： Hash functions

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A high efficient in-place transposition scheme for multidimensional arrays

A high efficient in-place transposition scheme for multidime...

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3rd International Conference on Information and Computing, ICIC 2010

作者： Yuan, Jie Wu, Jian-Ping Wang, Zheng-Hua National Lab. of Parallel and Distributed Processing National University of Defense Technology Changsha China School of Computer Science National University of Defense Changsha China

ISBN: (纸本)9780769540474

This paper presents a in-place cycle-reducing method for multidimensional arrays transposition in local memory to reduce the memory R/W operations. The resulting method can significantly reduce the number of subcycles (also called following-cycles) and that of memory operations for square arrays. Taking square array 256 by 256 for example, the number of subcycles used by current available best algorithm can be reduced from 32894 to only 574, using our new method, and the memory operation number can be reduced by about 32.58%, from 98430 to 66366. Taking advantage of this new method, the elapsed time can be reduced as a result. The number of cycles and operations can also be reduced for 2D rectangle arrays with 2m rows and 2n column stored in column-major, especially n=2m, even though the improvement is not as significant as that for square arrays. The improved 2D in-place algorithm has been extended to 3D arrays, and some theoretic and numerical results are also provided. Furthermore, we develop a new in-place 3D arrays transposition algorithm. This algorithm is very important for a deep research for multidimensional arrays. Experimental results show that our algorithm can improve efficiency significantly, compared to some other 3D array transposition schemes. © 2010 IEEE.

关键词： Multidimensional array Memory operation Cycle-reducing Transposition In-place transposition Transposition arrays three-dimensional array Local Memory MULTIDIMENSIONAL

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Inducing taxonomy from tags: An agglomerative hierarchical clustering framework

Inducing taxonomy from tags: An agglomerative hierarchical c...

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8th International Conference on Advanced Data Mining and Applications, ADMA 2012

作者： Li, Xiang Wang, Huaimin Yin, Gang Wang, Tao Yang, Cheng Yu, Yue Tang, Dengqing National Laboratory for Parallel and Distributed Processing School of Computer Science National University of Defense Technology Changsha China College of Mechatronics Engineering and Automation National University of Defense Technology Changsha China

ISBN: (纸本)9783642355264

By amassing 'wisdom of the crowd', social tagging systems draw more and more academic attention in interpreting Internet folk knowledge. In order to uncover their hidden semantics, several researches have attempted to induce an ontology-like taxonomy from tags. As far as we know, these methods all need to compute an overall or relative generality for each tag, which is difficult and error-prone. In this paper, we propose an agglomerative hierarchical clustering framework which relies only on how similar every two tags are. We enhance our framework by integrating it with a topic model to capture thematic correlations among tags. By experimenting on a designated online tagging system, we show that our method can disclose new semantic structures that supplement the output of previous approaches. Finally, we demonstrate the effectiveness of our method with quantitative evaluations. © Springer-Verlag Berlin Heidelberg 2012.

关键词： Taxonomies

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