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SWN: An SDN Based Framework for Carrier Grade WiFi networks

China Communications 2016年第3期13卷 12-26页

作者： LEI Tao WEN Xiangming LU Zhaoming ZHAO Xing LI Yangchun ZHANG Biao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications

With the rapid growth of mobile data traffic and vast traffic offloaded from cellular network, Wi-Fi has been considered as an essential component to cope with the tremendous growth of mobile data traffic. Although operators have deployed a lot of carrier grade Wi-Fi networks, but there are still a multitude of arrears for nowadays Wi-Fi networks, such as supporting seamless handover between APs, automatic network access and unified authentication, etc. In this paper, we propose an SDN based carrier grade Wi-Fi network framework, namely SWN. The key conceptual contribution of SWN is a principled refactoring of Wi-Fi networks into control and data planes. The control plane has a centralized global view of the whole network, can perceive the underlying network state by network situation awareness(NAS) technique, and bundles the perceived information and network management operations into northbound Application Programming Interface(API) for upper applications. In the data plane, we construct software access point(SAP) to abstract the connection between user equipment(UE) and access point(AP). network operators can design network applications by utilizing these APIs and the SAP abstraction to configure and manage the whole network, which makes carrier grade Wi-Fi networks more flexible, user-friendly, and scalable.

关键词： SWN carrier grade Wi-Finet works SDN seamless handover load balancing Hotspot 2.0 traffic offloading

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Reduced frame set on wireless distorted video for quality assessment

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The Journal of China Universities of Posts and Telecommunications 2016年第4期23卷 77-82,100页

作者： Shao Hua Wen Xiangming Lu Zhaoming Chen Yawen Lu Jingyu Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Objective video quality assessment methods often evaluate all the frames regardless of their importance. For wireless distorted videos, not every frame has the same contribution to the final overall quality due to the channel fading and interference, which may lead to the capacity variation in temporal. Besides, with the content similarity and error propagation pattern in temporal domain, it is possible to evaluate the overall quality with only part of the frames. In this paper, a demonstration is performed to show that the video quality can be evaluated with reduced frames set（RFS）, and a state transition model is proposed to extract the RFS. At last, a video quality assessment（VQA） method is carried out based on RFS. Compared with several state-of-the-art methods, our method can achieve a suitable accuracy with less frames to be processed.

关键词： VQA wireless distortion quality of experience

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A joint learning and communications framework for federated learning over wireless networks

arXiv

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arXiv 2019年

作者： Chen, Mingzhe Yang, Zhaohui Saad, Walid Yin, Changchuan Vincent Poor, H. Cui, Shuguang Chinese University of Hong Kong Shenzhen518172 China Department of Electrical Engineering Princeton University PrincetonNJ08544 United States Centre for Telecommunications Research Department of Informatics King's College London WC2B 4BG United Kingdom Bradley Department of Electrical and Computer Engineering Virginia Tech BlacksburgVA24060 United States Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China Department of Electrical Engineering Princeton University PrincetonNJ08544 United States Shenzhen Research Institute of Big Data School of Science and Engineering Chinese University of Hong Kong Shenzhen518172 China

In this paper, the problem of training federated learning (FL) algorithms over a realistic wireless network is studied. In particular, in the considered model, wireless users execute an FL algorithm while training their local FL models using their own data and transmitting the trained local FL models to a base station (BS) that will generate a global FL model and send it back to the users. Since all training parameters are transmitted over wireless links, the quality of the training will be affected by wireless factors such as packet errors and the availability of wireless resources. Meanwhile, due to the limited wireless bandwidth, the BS must select an appropriate subset of users to execute the FL algorithm so as to build a global FL model accurately. This joint learning, wireless resource allocation, and user selection problem is formulated as an optimization problem whose goal is to minimize an FL loss function that captures the performance of the FL algorithm. To address this problem, a closed-form expression for the expected convergence rate of the FL algorithm is first derived to quantify the impact of wireless factors on FL. Then, based on the expected convergence rate of the FL algorithm, the optimal transmit power for each user is derived, under a given user selection and uplink resource block (RB) allocation scheme. Finally, the user selection and uplink RB allocation is optimized so as to minimize the FL loss function. Simulation results show that the proposed joint federated learning and communication framework can reduce the FL loss function value by up to 10% and 16%, respectively, compared to: 1) An optimal user selection algorithm with random resource allocation and 2) a standard FL algorithm with random user selection and resource allocation. Copyright © 2019, The Authors. All rights reserved.

关键词： Learning algorithms

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Energy efficient channel sharing and power optimization for device-to-device networks

Lecture Notes of the Institute for Computer Sciences, Social...

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Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST 2017年 174卷 63-75页

作者： Xi, Zeguo Wen, Xiangming Lu, Zhaoming Zeng, Yan Hu, Zhiqun Lei, Tao Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China Beijing Laboratory of Advanced Information Networks Beijing100876 China

In device-to-device (D2D) networks, the system performance can be significantly improved with a well resource allocation scheme. In this paper, the issue of channel sharing and power allocation for deviceto-device (D2D) communications underlaying cellular networks is considered. The users with the same service content are categorized into clusters, with clusters sharing the frequency of the uplink users. With this non-orthogonal frequency sharing, the energy efficiency of different type of users, i.e., the uplink users or the D2D users, is analysed. The energy-efficient resource sharing problem is further formulated into a non-transferable coalition formation game, and several related factors of the game is described. A distributed coalition formation game algorithm based on the merge and split rule is proposed. With numerical results, the effectiveness of the game model and the algorithm is demonstrated. © ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2017.

关键词： Energy efficiency

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Analysis and Prediction of Content Popularity for Online Video Service:A Youku Case Study

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China Communications 2016年第12期13卷 216-233页

作者： Chenyu Li Jun Liu Shuxin Ouyang Beijing Key Laboratory of Network System Architecture and Convergence Center for Data ScienceSchool of Information and Communication EngineeringBeijing University of Posts and Telecommunications

Understanding the characteristics and predicting the popularity of the newly published online videos can provide direct implications in various contexts such as service design, advertisement planning, network management and etc. In this paper, we collect a real-world large-scale dataset from a leading online video service provider in China, namely Youku. We first analyze the dynamics of content publication and content popularity for the online video service. Then, we propose a rich set of features and exploit various effective classification methods to estimate the future popularity level of an individual video in various scenarios. We show that the future popularity level of a video can be predicted even before the video's release, and by introducing the historical popularity information the prediction performance can be improved dramatically. In addition, we investigate the importance of each feature group and each feature in the popularity prediction, and further reveal the factors that may impact the video popularity. We also discuss how the early monitoring period influences the popularity level prediction. Our work provides an insight into the popularity of the newly published online videos, and demonstrates promising practical applications for content publishers,service providers, online advisers and network operators.

关键词： online content popularity online video service popularity characterization popularity prediction

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Impedance measurement of RFID tag antenna based on different methods

Impedance measurement of RFID tag antenna based on different...

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IEEE International Symposium on Electromagnetic Compatibility (EMC-beijing)

作者： Chenwei Cai Weijun Hong Li Deng Shufang Li Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing People's Republic of China

RFID tag antennas use balanced feeding structure, which causes great challenge on antenna impedance measurement. Methods for balanced antenna impedance measurement can be divided into three categories: Balun method, imaging theory and S-parameter method. Three types methods are analyzed and compared in this paper. Simulations and experiments are implemented to support the comparison. Through the comparisons, great agreements in impedance value and variation tendency are observed between the simulation and experiment. Moreover, strengths and weaknesses of the three methods also are analyzed in this paper.

关键词： Antenna measurements Impedance Scattering parameters Dipole antennas Impedance measurement Imaging

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A SOFTWARE DEFINED SECURITY architecture FOR SDN-BASED 5G network 5

A SOFTWARE DEFINED SECURITY ARCHITECTURE FOR SDN-BASED 5G NE...

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2016 5th IEEE International Conference on network Infrastructure and Digital Content(IC-NIDC 2016)

作者： Xiaodong Liang Xiaofeng Qiu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

ISBN: (纸本)9781509012473

Software Defined networking(SDN) is considered to meet the future needs of the 5G mobile ***,there have been only a few works so far that address the security issues in SDMN(Software Defined Mobile networks),and all the proposed approaches have their ***,in this context,a new security paradigm based on SDN introduces many opportunities and provides the potential to solve the security problem in the mobile core *** this paper,we present the SDS-SC,a software defined security architecture for SDN based 5G *** centralized security controller that communicates with SDN network controller,flexible and network-aware security services could be provided for mobile users *** also highlight how security applications could be developed easily in our architecture through application interface on top of the security controller.

关键词： 5G SDN Security architecture

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network ANOMALY DETECTION BASED ON FREQUENT SUB-GRAPH MINING APPROACH AND ASSOCIATION ANALYSIS 5

NETWORK ANOMALY DETECTION BASED ON FREQUENT SUB-GRAPH MINING...

引用

2016 5th IEEE International Conference on network Infrastructure and Digital Content(IC-NIDC 2016)

作者： Fangyuan Cheng Xiaofeng Qiu Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

ISBN: (纸本)9781509012473

In this paper,an anomaly detection method based on frequent sub-graph mining and association analysis is introduced to ensure the security of the *** this method,the network behavior data in SDN are represented as a graph,abnormal sub-graphs of which are readily *** patterns of the detected abnormal behaviors are able to be ***,an ensemble method based on Bagging algorithm is proposed to improve the detection *** with global flow table data based on SDN indicated that this approach was capable of detecting anomalies in ***,to illustrate the effectiveness of this method in other aspects,comparisons with KDD99 data set were *** the results verified its excellent ability in reducing false alarms and the effect of the ensemble method on improving the detection accuracy.

关键词： Security for SDN Anomaly detection Frequent sub-graph mining Bagging ensemble method

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Signal Recognition Based on Signal Power Spectrum Fitting Feature Extraction

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beijing Youdian Daxue Xuebao/Journal of beijing University of Posts and Telecommunications 2018年第2期41卷 114-118页

作者： Tian, Hao-Min Yin, Liang Ma, Yue Li, Shu-Fang Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing100876 China Computer Network Research Center Beijing University of Posts and Telecommunications Beijing100876 China School of Computer Science and Technology Beijing University of Posts and Telecommunications Beijing100876 China

Aiming at the problem of communication signal service type identification, the author proposes a polynomial fitting factor that extracts the power spectrum of the signal using the linear regression algorithm and the polynomial fitting model in machine learning field as a unified feature of the signal to construct the training set. A multi-layer fully connected neural network classifier model was built on depth learning platform. Compared with the traditional ones, this method has advantages of unifying the radio signal without the need of individual service to extract the personalized features. The power spectrum data of code division multiple access(CDMA) uplink, CDMA downlink, extended global system for mobile(EGSM) uplink, EGSM downlink, wireless local area networks (WLAN) and long time evolution (LTE) signals in the actual radio monitoring data are selected as data set, and 97% classification accuracy is verified. that this method is proven feasible. © 2018, Editorial Department of Journal of beijing University of Posts and Telecommunications. All right reserved.

关键词： Extraction

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Probabilistic Top-k Query:Model and Application on Web Traffic Analysis

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China Communications 2016年第6期13卷 123-137页

作者： Xiaolin Gui Jun Liu Qiujian Lv Chao Dong Zhenming Lei Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and TelecommunicationsBeijing100876China Agricultural Bank of China Beijing 100161 China

Top-k ranking of websites according to traffic volume is important for Internet Service Providers(ISPs) to understand network status and optimize network resources. However, the ranking result always has a big deviation with actual rank for the existence of unknown web traffic, which cannot be identified accurately under current techniques. In this paper, we introduce a novel method to approximate the actual rank. This method associates unknown web traffic with websites according to statistical probabilities. Then, we construct a probabilistic top-k query model to rank websites. We conduct several experiments by using real HTTP traffic traces collected from a commercial ISP covering an entire city in northern China. Experimental results show that the proposed techniques can reduce the deviation existing between the ground truth and the ranking results vastly. In addition, we find that the websites providing video service have higher ratio of unknown IP as well as higher ratio of unknown traffic than the websites providing text web page service. Specifically, we find that the top-3 video websites have more than 90% of unknown web traffic. All these findings are helpful for ISPs understanding network status and deploying Content Distributed network(CDN).

关键词： top-k query traffic model temporal bipartite graph uncertain data unknown traffic

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