Research at flat underlying network architecture of campus by Chu-jian LIN, Si-hai ZHANG

“…By systematic analysis of the status quo on the campus network,via deployment of BRAS and high-density switches,we deployed a flat network core,by deployment of accounting system through a bypass way,using IPOE access technology,combined with local forwarding wireless networking,assisted with linkage logging system,we achieved a unified user access certification,and we optimized the network boundary by integrating of global security policy,strategies for Internet traffic optimization base on application protocols and the deployment of caching system.Practice shows,flat underlying network architecture improves the network performance,meets the inherent requirements of campus network,while also improves users’ experience.Flat network architecture is feasible for campus network.…”
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MicroNF:a microservice-based hybrid framework for NFV by Chen SUN, Jun BI, Zhilong ZHENG, Shuhe WANG, Hongxin HU

“…Network function virtualization (NFV) brought significant flexibility.However,such flexibility came with considerable compromises,since virtual machine carried monolithic functions could introduce significant performance overhead.A novel high-performance and programmable framework called MicroNF was proposed,which combines programmable hardware infrastructure and traditional software infrastructure in NFV to achieve both high performance and flexibility.In particular,microservice,a new design approach in software architecture,was leveraged by MicroNF to re-architect NFV to enable functional reusability among services and improve performance.MicroNF was implemented in a test bed based on OpenStack and ONetCard.Experimental results show that MicroNF reduces the forwarding latency of a service chain by an average of 70% compared with DPDK-based software implementation.…”
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Uneven clustering routing protocol based on dynamic partition for wireless sensor network by Yan-qing SUN, Jian PENG, Tang LIU, Xiao-hai CHEN

“…To solve the “hot spots” problem caused by uneven load energy,a novel distributed clustering routing protocol was proposed.Its core is an uneven clustering routing protocol based on dynamic partition(UCDP).In UCDP,the entire network’s energy consumption is balanced by dynamic partitioning,making the regions closer to the sink node with smaller nodes,which can preserve some energy for inter-region data forwarding.Considering the distance factor and residual energy factor for uneven clustering in each region,cluster-heads and region-heads work together in UCDP.Via the combination of single-hop and multi-hop,DBUP has established an optimal energy-balanced routing protocol.Simulation results show that UCDP has good stability,and significantly prolongs the network life.…”
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Traffic scheduling method based on centralized control in named data networking by Qian DONG, Jun LI, Yuxiang MA

“…In order to address the global optimization problem for traffic scheduling in named data networking,related works were analyzed,a method based on centralized control was proposed.The proposed method took network performance and communication overhead into account.In the proposed scheme,appropriate nodes would be selected as E-NDN nodes,then the controller calculated the corresponding multi-path forwarding policies and sent them to E-NDN nodes according to the in-network cache,the aggregation of Interest packets,and the traffic demands of popular contents to achieve global optimization.The evaluation results indicate that the proposed method can significantly reduce the maximum link utilization and improve network performance.Simultaneously,the proposed method will not cause a large optimization cost,and communication overhead between the controller and nodes will increase slightly.…”
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Turismo, patrimônio e políticas públicas na Amazônia Maranhense by Linda Maria Rodrigues

“…In this sense, nature, the tourism sector's greatest appeal, forwards in Maranhão, the first steps of a period of investments, entitled Plano Maior, whose objective was to “transform Maranhão into one of the biggest ecotourism destinations in the country”. …”
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Journalists’ Response and Reporting of Public Emergencies in the Era of Artificial Intelligence by Shaoying Lian, Ruoyu Mi, Runhua Tang

“…In the simulation analysis, it is found that in the face of public emergencies, journalists, on the one hand, firmly implement the publicity caliber, strengthen the amount of creation, and improve the forwarding amount and approval amount of manuscripts under the artificial intelligence news system. …”
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Portuguese Architecture in Transit(ion) by Bruno Gil, Susana Lobo, José Ribau Esteves

“…From a national context, politically and geographically distant from the heart of the disciplinary debate of the 1960s, the proposals submitted set the terms on which Portugal competes in Amsterdam, revealing in the diversity of approaches and experiences forwarded by this new generation of architects the vitality of Portuguese architecture on its path to internationalisation. …”
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Após a nacionalidade: história do romance e produção romanesca no Brasil e na América Latina by Pedro Dolabela Chagas

“…Finally, the readings of some contemporary authors synthesize the propositions forwarded.…”
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Performance analysis of two-way relay cooperation underlay cognitive radio networks based on WIPT by Jisheng XU, Fanzi ZENG, Kang LI, Yongfeng LI

“…The two-way relay cooperation for underlay cognitive radio networks based on WIPT was presented,where secondary system adopted the two-way relay cooperative transmission.First,the relay adopted a power splitting protocol to harvest energy and to decode information transmitted by secondary users,then the relay forwarded information to two secondary users by using the harvested energy.Subsequently the exact expression of the outage probability,the ergodic capacity and energy efficiency of the secondary user system were derived.Finally,numerical simulation discusses the impact on the system performance with regard to secondary transmission power.The results reveal that the two-way relay cooperation effectively reduces the outage probability of data transmission.The capacity and energy efficiency of the system reaches optimal level when the power allocation coefficient is 0.5.…”
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Load-balanced self-routing switching structure by LI Hui1, WANG Bing-rui1, HUANG Jia-qing3, AN Hui-yao1, LEI Kai1, YI Peng4, WANG Bin-qiang4

“…With simple algorithms and small buffers, the first stage structure transformed the arriving traffic into uniform and the second stage forwarded the data in a self-routing manner to their final destinations. …”
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Motion state-based data delivery scheme of delay tolerant mobile sensor networks by YANG Kui-wu1, ZHENG Kang-feng1, YANG Yi-xian1, GUO Shi-ze1, WU Bin1

“…A motion state-based data delivery scheme（MSD） was proposed for delay tolerant mobile sensor network.By using the broadcasting signal of base station on the frequency of f1,sensor nodes could compute their own motion stated and delivery probabilities which provided the bases for messages transmitting between nodes on the frequency of f2.In order to improved network performance,MSD employed the message survival time and prior forwarding mechanism of own messages to manage the message queue.Simulation results show that the proposed MSD data delivery scheme has a higher message delivery ratio with lower transmission cost and less data delivery delay than other DTMSN（delay tolerant mobile sensor networks） data delivering approaches.…”
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Performance of multiple-source single-relay ultra-wideband networks based on space-time focusing transmission by Ya-fei TIAN, Chen-yang YANG

“…Space-time focusing transmission can reduce multi user interference in ultra-wideband (UWB) communications.Thus enable one relay forwarding the data from multiple sources to multiple destinations.Performance of relay networks with space-time focusing transmission was studied.The outage probabilities in multiple-access phase and broadcasting phase were derived,respectively.The explicit connection between the network throughput and the user number,distance between nodes,UWB pulse width,signal frame duration,and the received signal-to-interferenceand-noise ratio was obtained.By maximizing the network throughput and ana zing the optimization results,some design guidelines for the transmission scheme were provided.The outage probabilities in the two phases were verified through simulations under different path loss factors.…”
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Construction technologies of polymorphic network environment based on codesign of domain-specific software/hardware by Yuxiang HU, Zixi CUI, Ziyong LI, Yongji DONG, Pengshuai CUI, Jiangxing WU

“…The deeply integration of information network and economic society has brought the trend of symbiotic coexistence, dynamic concurrency, evolution and revolution of network modals.Firstly, in order to satisfy the requirements of vertical industry applications, a scheme of the polymorphic network element based on codesign of domain-specific hardware/software was proposed, the key technologies to construct polymorphic network environment were discussed as well.Then, to solve the resource competition problem between diversified network modals, a heterogeneous resource allocation and replacement method was proposed by integration of computing, storage and forwarding, which dynamically adjusted the resource-allocation strategy according to the traffic volume to realize the efficient resource utilization.Experimental results show that the proposed scheme can provide the basic platform support for the construction of polymorphic network by separation of technical systems and supporting environment.…”
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Deadline Aware Retransmission Threshold Setting Protocol in Cyber-Physical Systems by Ran Bi, Jianzhong Li, Hong Gao, Quan Chen

“…To avoid dropping the packet forwarded to the destination within given deadline with high probability, we develop a packet dropped protocol based on probabilistic delay bound. …”
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In-band network telemetry system based on high-performance packet processing architecture VPP by Tian PAN, Xingchen LIN, Jiao ZHANG, Tao HUANG, Yunjie LIU

“…An in-band network telemetry-based system was built based on VPP, a high-performance virtual network forwarding architecture/device, via reorganizing the data plane pipeline processing modules.Moreover, a network-wide telemetry mechanism was further developed via embedding source routing into the probe packet header for specifying the route of probe packets.Finally, a virtual network topology was built with performance evaluation conducted.The evaluation shows that the telemetry system can monitor the network in a high precision of every 0.13 ms, detecting link congestion in real time with minor performance overhead.Given virtual network devices have been widely deployed in data centers, the proposed scheme is expected to improve the reliability of multi-tenancy and network function virtualization in data centers via high-precision, network-wide virtual link telemetry coverage.…”
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Resource optimization algorithm of combination of NFV and SDN for application of multiple services by Xiaorong ZHU, Qian ZHANG

“…Various services of internet of things (IoT) require flexible network deployment to guarantee different quality of service (QoS).Aiming at the problem of IoT service function chain deployment,network function virtualization (NFV) and software defined networking (SDN) were combined to optimize resources.Considering forwarding cost and traffic load balance,a joint optimization model of virtual network function placement and service function chain routing was given and was proved to be NP-Hard.In order to solve this model,two heuristic algorithms were proposed.One was the service chain deployment algorithm of first routing then placing (FRTP) and the other was the placing followed by routing (PFBR) based on node priority.Simulation results demonstrate that FRTP and PFBR algorithm can significantly balance network traffic load while alleviating congestion and improving the acceptance ratio of the chain requests compared with other algorithms.…”
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SD-WAN tunnel technology and network constuction by Jia NIU, Yongming YAN, Zhihua LIN

“…The status of SD-WAN technology was introduced, the SD-WAN advantages with traditional line were compared.The basic technical features of SD-WAN, the software definition network controllers of SD-WAN, security encryption and tenant isolation, the SD-WAN industry standards were described.The relevant technologies of SD-WAN main manufacturers were also analyzed, the tunnel technology used by SD-WAN was compared.And private IPSec tunnel , VxLAN over IPSec, NvGRE over IPSec, SSL tunnel network project used by the different companys was compared and analyzed, the optimized tunnel technology project was given, and optimizational suggestions on how to use tunnel technology to complete networking project were further put forwarded, combined with the advantages of Internet service product in establishing SD-WAN, the POP network and peer-to-peer networking solutions were given.Finally, it make future development prospect for SD-WAN standards, Internet service product and SD-WAN manufacturers trends.…”
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Routing optimization based on topology control in satellite network by Xiaogang QI, Jiulong MA, Lifang LIU

“…A new double-layer satellite network model for space networking was established and a routing algorithm based on topology control (TCRA) was proposed considering the advantages of low earth orbit and stationary earth orbit satellite networks.This model used virtual node strategy and satellite grouping idea,which regarded the coverage area of each low earth orbit satellite as a virtual node.The network took into account the influence of the polar area on the division of the satellite footprints,such that the upper management satellites can accurately acquire the topology of the lower satellites.Using the improved virtual node strategy,the time slices were superior to other network models in quantity,length and other aspects.Based on the network topology,stationary earth orbit satellites calculate routing for low earth orbit satellites,while low earth orbit satellites were responsible for forwarding data.The simulation results show that the routing algorithm is superior to other algorithms in average end-to-end delay and packet loss rate.…”
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Programmable data processing method and system design for polymorphic network by Jinlin WANG, Li’nan JING, Xiao CHEN, Jiali YOU

“…Aiming at the problems of compatible with multiple route identification, network protocols and network application data processing faced by multimodal networks, a programmable data processing method compatible with multiple modes was proposed.Through the mode recognition and classify module to identify packets of different network modes, the data type, offset and length were used to represent multiple types of data, and the modal data processing pipeline was formed by using the matching action data table with selectable matching algorithm and processing action to process data of different types of network.A prototype system for data processing of polymorphic network was implemented and verified by using the proposed method.Experimental results show that the modal data processing pipeline can isolate the network of different modes and ensure the performance independence, the type of matching algorithm and the length of the processed data will affect the forwarding performance of the system, while the type of data will not.…”
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MCKite: A Multi-Producer Multicast Scheme in Named Data Networking by Yu Zhang, Yanbin Sun, Hongli Zhang

“…MCKite made topological positions of producers transparent to other producers and consumers, so that routing/forwarding information bases didn't need to be created beforehand or be updated which reduced the complexity of protocol. …”
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