最新刊期

    卷 34 , 期 7 , 2018

      View the focus

    • Toward a new era of digital economy

      Chuncong LU
      Vol. 34, Issue 7, Pages: 1-6(2018) DOI: 10.11959/j.issn.1000-0801.2018220
      摘要:The digital economy is to supply digital elements with rich elements,improve the efficiency of factor allocation by network,improve output efficiency intelligently,and promote economic development quality change,efficiency change,and power change.Firstly,the importance of grasping the new opportunities for the development of the digital economy was explained.Then the rapid growth of the digital economy and the significant situation of the digital economy driving employment was introduced.Finally,key points of promoting the development of the digital economy were focused on.The next step is to accelerate the application of industrial internet construction,promote the digital transformation of enterprises,improve the policy environment,strengthen the protection of factors,and further promote the prosperity and development of the digital economy.  
      关键词:digital economy;scale;high quality development;employment   
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      Topic:SDN/NFV technology and application

    • Yuan ZHANG
      Vol. 34, Issue 7, Pages: 7-14(2018) DOI: 10.11959/j.issn.1000-0801.2018211
      摘要:The network on demand is mainly based on SDN,NFV and cloud technologies,which realizes the softening,automation and intelligence of the network and provides users with the ability to configure the network on demand.The architecture and key technologies of the network on demand were emphasized,and the collaborative orchestration was introduced.The SDN,NFV network and cloud resources were arranged,and the network path was quickly established by introducing the SD-WAN overlay technology,and four application scenarios of the network on demand for small and medium enterprises were proposed.Network on demand can provide customers with a new web experience of “visual” “on-demand” and “self-service”.  
      关键词:network on demand;software defined networking;network function virtualization;cloud computing;orchestrator   
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    • SDN solutions for cloud data center

      Cui ZHONG, Lei WANG, Xing LUO
      Vol. 34, Issue 7, Pages: 15-22(2018) DOI: 10.11959/j.issn.1000-0801.2018213
      摘要:The design concept of SDN is to pool and manage network resources,automate the on-demand application and call of network resources,and accelerate the online cycle of data center services.Firstly,the core idea of data center SDN and the panoramic view of SDN open architecture was introduced.Then,the SDN network model and SDN service deployment plan was introduced.Finally,solution of Huawei CloudFabric cloud data center network was described.  
      关键词:software defined networking;data center;automation   
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    • Telecom cloud solution in re-architecture of MAN

      Ding CHEN, Tao ZHANG, Ke LIU, Qiang LAN
      Vol. 34, Issue 7, Pages: 23-34(2018) DOI: 10.11959/j.issn.1000-0801.2018219
      摘要:Evolving the legacy network to SDN/NFV network is the strategy of carrier network re-architecture.Based on large-scale cases,multi-tier data centers architecture,application-driven telecom cloud infrastructure,vBRAS pool and C-U separation solutions were proposed.Session-consumed services and IPTV are the first several services that can be implemented by the new solution in MAN.And in those usecases,the carriers’ operators really combine the IT and CT operation teams into one virtual team,and push the evolution gradually.  
      关键词:network re-architecture;telecom cloud;SDN/NFV;vBRAS;control-user plane separation   
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    • Architecture and key technology of telco edge cloud

      Qiao FU, Xiaodong DUAN, Lu WANG, Yamei FAN
      Vol. 34, Issue 7, Pages: 35-40(2018) DOI: 10.11959/j.issn.1000-0801.2018218
      摘要:With the increased requirement for low latency,high bandwidth and artificial intelligence for future network,the concept of edge cloud,which could bring network service closer to end users,has become a hot topic recently.For now,the understanding and study on edge cloud is still at the startup phase,with no end-to-end framework and solution yet.Combining with the network transformation requirement for the telco network,and the newly emerging edge service,a typical framework and multiple key features were proposed.And the possible solutions for edge cloud related technologies was provided to try to bring insight for the future edge cloud development.  
      关键词:NFV;SDN;telco edge cloud   
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    • NFP:enabling network function parallelism in NFV

      Jun BI, Chen SUN, Heng YU
      Vol. 34, Issue 7, Pages: 41-48(2018) DOI: 10.11959/j.issn.1000-0801.2018216
      摘要:Software-based sequential service chains in network function virtualization (NFV) could introduce significant performance overhead.Current acceleration efforts for NFV mainly target on optimizing each component of the sequential service chain.However,based on the statistics from real world enterprise networks,it was observed that 53.8% network function (NF) pairs could work in parallel.In particular,41.5% NF pairs could be parallelized without causing extra resource overhead.NFP was presented,a high performance framework,that innovatively enabled network function parallelism to improve NFV performance.NFP consisted of three logical components.Firstly,NFP provided a policy specification scheme for operators to intuitively describe sequential or parallel NF chaining intents.Secondly,NFP orchestrator intelligently identified NF dependency and automatically compiled the policies into high performance service graphs.Thirdly,NFP infrastructure performed light-weight packet copying,distributed parallel packet delivery,and load-balanced merging of packet copies to support NF parallelism.An NFP prototype based on DPDK in Linux containers was implemented.The evaluation results show that NFP achieves significant latency reduction for real world service chains.  
      关键词:NFV;network function parallelism;service chain   
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      research and development

    • Network resource pricing strategy based on SDN framework

      Bin ZHUGE, Yihang QI, Hanwen FU, Weiming WANG
      Vol. 34, Issue 7, Pages: 49-61(2018) DOI: 10.11959/j.issn.1000-0801.2018173
      摘要:A network resource pricing strategy based on SDN framework was proposed to solve the problem of resource overload and network congestion caused by resource requests in the network.Firstly,the user’s needs and consumption patterns were analyzed,and the resource transaction model was determined.Secondly,combined with the spot consumption model and plan consumption,the reservation mechanism under the resource dynamic pricing strategy model was determined.Finally,according to the proposed resource pricing strategy,the resource price was simulated,the results show that by stimulating the user to reserve resources in advance and combining the trust degree and consumption habits of each user with corresponding preferential prices,it is possible to effectively avoid the users from obtaining network resources in a centralized manner.  
      关键词:software defined networking;network resource;user requirement;pricing strategy   
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    • Yupei ZHANG, Zhijin ZHAO, Shilian ZHENG
      Vol. 34, Issue 7, Pages: 62-71(2018) DOI: 10.11959/j.issn.1000-0801.2018114
      摘要:At present,a single target optimization function is often used in channel design.While in order to meet the large capacity real-time transmission,it is necessary to consider the cumulative delay and channel capacity simultaneously.The multi-objective function of the target channel design was constructed,and discrete multi-objective particle swarm optimization algorithm(DMOPSO) was proposed to solve it.The discretization design of the population coding and updating was given.The simulation results show that the optimal channel set obtained by proposed spectrum handoff algorithm can take into account the real-time and high throughput of the network,while needing the low complexity.  
      关键词:multi-objective optimization;spectrum handoff,;cumulative delay;channel capacity;particle swarm optimization   
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    • Chuanyun WANG, Min WANG, Junhui ZHAO, Yan YIN
      Vol. 34, Issue 7, Pages: 72-79(2018) DOI: 10.11959/j.issn.1000-0801.2018199
      摘要:A dual mode switching channel estimation algorithm based on SNR decision in high speed railway scenarios was proposed.The algorithm adopted DKL-BEM and LMMSE modelling the channel and estimating the channel under different speed conditions,respectively.The simulation results show that the SNR increased,the performance of the twice channel estimation algorithm based on ICI cancellation became worse than that of the traditional DKL-BEM algorithm,and a cross-point appeared,its value moved towards the small SNR as the speed increased.Through analyzing the parameters and extracting the cross-point values of the two algorithms,the moving trajectory of the cross-point with the speed changing was given.The proposed algorithm can adaptively achieve the switching between two algorithms and improve the applicability and effectiveness of the channel estimation algorithm.  
      关键词:high speed railway scenario;dual mode switching;adaptive;cross-point;time-varying channel   
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    • Ji JIANG, Mugen PENG, Wenbo WANG
      Vol. 34, Issue 7, Pages: 80-85(2018) DOI: 10.11959/j.issn.1000-0801.2018172
      摘要:Nowadays,the land communication system is unable to support the complex information needs,and realizing global seamless coverage and high capacity through space information network is anticipated.The existing satellite network is mainly composed of single satellite constellation,which absents the cooperation between the low earth orbit (LEO) satellites and geostationary orbit (GEO) satellites.A double-layer satellite constellation based on distributed satellite clusters was proposed,in which the infrastructure layer was composed of LEO satellites,the communication between LEO satellites was accomplished over inter-satellite links (ISL),and GEO satellites enhance the performance of coverage in low and middle latitudes.As simulation results show,the proposed approach can realize excellent global multiple coverage only relying on the deployment of satellite earth stations in China.  
      关键词:space information network;constellation design;satellite collaboration;distributed satellite cluster   
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    • Wenbo WANG, Qingwei YE, Yu ZHOU, Zhihua LU
      Vol. 34, Issue 7, Pages: 86-91(2018) DOI: 10.11959/j.issn.1000-0801.2018204
      摘要:Internet communication,computer cluster and cloud environment have complex and dynamic characteristics,which can cause load imbalance easily,reduce the service efficiency and increase the energy consumption.Therefore,the load balancing technology becomes the focus of research.The existing load balancing strategy uses the occupancy of CPU,memories,processes to estimate the current load of each server.But it is hard to guarantee its accuracy.Aiming at this problem,a dynamic load balancing algorithm based on queuing theory comprehensive index evaluation was proposed.Firstly,queuing theory model was introduced to estimate the real-time load of each server,and then the tasks of input queue was distributed to each server separately according to the load comprehensive index of each server.Experimental results show that this method can balance the load of each server effectively and reduce the average waiting time of the task requests,which is of great application value.  
      关键词:load balancing;queuing theory;performance   
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    • Intelligent optimization algorithm based on benchmarking

      Anshi XIE
      Vol. 34, Issue 7, Pages: 92-101(2018) DOI: 10.11959/j.issn.1000-0801.2018144
      摘要:Many of the issues in scientific research,engineeringand management can be transformed into optimization problems.The various methods applied to these problems were a variety of models.Designing different methods was designing different models.The theme was to model the benchmarking philosophy in business management as a meta-heuristic search method for single objective bound-constrained real-parameter optimization problems.According to the principle of Occam’s Razor,many complicated operators and their probability tuning rules were abandoned and a simple framework was used to organize the core operators to achieve the effect of many composition algorithms.  
      关键词:intelligent optimization algorithm;exploration and exploitation;global search and local optimization;benchmarking management   
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    • Rui HAN, Lei ZHANG, Wei LI, Shanshan LIU, Guan WANG, Chunhua LIU
      Vol. 34, Issue 7, Pages: 102-109(2018) DOI: 10.11959/j.issn.1000-0801.2018137
      摘要:Based on the Agenda Item 1.13 of WRC-19 and requirements for domestic compatibility analysis of 5G candidate frequency bands above 6 GHz,the interference from IMT-2020 system (5G) to broadcasting satellite service system in 24.65~25.25 GHz band was studied.The Monte Carlo simulation method was used to assess the aggregate interference from IMT base station (BS) to the up-link of feeder link of broadcasting satellite where the geostationary orbit satellite at 59℃,85℃ and 113℃ longitude.The aggregate interference level from 5G system to the two kinds of carriers of the satellite system with different orbits was evaluated via simulation analysis.Research results show that the IMT-2020 (5G) system will not cause harmful interference for broadcasting satellite services system.The results can provide technology basis for future planning of IMT-2020 (5G) system in millimeter wave and protecting of broadcasting satellite system.  
      关键词:communication technology;IMT-2020(5G) system;interference analysis;broadcasting satellite service system   
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    • Xiu WANG, Qing CHANG, Yaoli WANG
      Vol. 34, Issue 7, Pages: 110-117(2018) DOI: 10.11959/j.issn.1000-0801.2018208
      摘要:The estimation of the direction of arrival of two-dimensional space signals is the key problem in the field of array antennas.Although the traditional two-dimensional MUSIC algorithm has high precision,it needs two dimensional spectrum peak search and has a large amount of operation.A two-dimensional DOA estimation algorithm for L-shaped array was proposed.The output matrix was transformed from a complex value matrix to a real value matrix by matrix reconstruction and a unitary transformation matrix.This method could directly get the elevation angle of the target without conversion,which greatly reduced the amount of operation.Compared with the matrix enhancement and matrix pencil algorithm for L-shaped array,this algorithm could estimate more targets’DOA.The results of simulation show that the algorithm has a high accuracy of DOA estimation.  
      关键词:direction of arrival;L-shaped array;unitary transformation matrix;eigenvalue;matrix enhancement and   
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    • A static MEH handover scheme based on load balancing

      Haipeng LIU
      Vol. 34, Issue 7, Pages: 118-127(2018) DOI: 10.11959/j.issn.1000-0801.2018183
      摘要:Based on the MEH (mobile edge host) handover scheme proposed by ETSI (European Telecommunications Standards Institute),an improved and supplementary static handover scheme was put forward.By transferring the former C-MEH (controlling MEH) to a neighbor server with lighter load,the scheme decreased the average waiting time of a signal message at the former C-MEH site.The negative effect of bottle-neck at the former C-MEH could also be lightened.Analysis and simulation results show that the scheme can provide effective and positive supplementary to the ETSI specification in balancing network load and improving user’s satisfaction.  
      关键词:5G;mobile edge computing;handover;load balancing   
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    • Songbai LIANG, Feng CHEN, Haiping SONG, Wensheng LI
      Vol. 34, Issue 7, Pages: 128-134(2018) DOI: 10.11959/j.issn.1000-0801.2018212
      摘要:In order to improve the accuracy and efficiency of the discovery of the antenna-feeder problem,an optimal direction angle solution based on Gaussian distribution was proposed to diagnose the antenna-feeder coverage problems of operators.First of all,the location direction information between each MR sampling point reported by the UE and the base station was calculated,and then the proportion of MR sampling points in each interval was calculated,Based on the Gaussian distribution feature,the angle range with the largest proportion of MR sampling points was the appropriate azimuth,which was based on the user hotspot distribution of the sector.Finally,the date of optimal azimuth was compared with the base station azimuth in the background antenna database to detect antenna feeder problems,such as cross feeder,improper antenna coverage direction and incorrect background antenna database,and so on.The field verification shows that,the cost,accuracy and efficiency of the antenna-feeder problems are obviously improved compared with the existing methods.  
      关键词:Gaussian distribution;MR;antenna;azimuth;positioning algorithm   
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      summarize

    • Security of intelligent edge computing:a survey

      Xingshuo AN, Guixing CAO, Li MIAO, Shubo REN, Fuhong LIN
      Vol. 34, Issue 7, Pages: 135-147(2018) DOI: 10.11959/j.issn.1000-0801.2018181
      摘要:With the rise of edge computing,more and more attentions have been paid to security issues of edge computing.The basic concepts,system architecture and the relationship between edge computing and other computing paradigms were introduced.Then the security threats to edge computing were analyzed,and the security technology of edge computing was discussed for these security threats.Finally,the technologies of intrusion detection,access control,defense strategy and key management in edge computing were summarized and the further research directions were pointed out.  
      关键词:edge computing;security technology;system framework   
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      Operating technology is extensive

    • Future architecture and evolution of communication network

      Sheng ZHANG, Wei RONG
      Vol. 34, Issue 7, Pages: 148-156(2018) DOI: 10.11959/j.issn.1000-0801.2018215
      摘要:With the rapid development of the internet,the network bearer content is gradually transformed from a service based on connection-based information interaction to a service based on content sharing (video).The network transmits a large amount of redundant information,resulting in abnormal large-scale investment.And the quality of the service is difficult to guarantee,and it is urgent to study and construct a network that matches the business development.The content sharing connection relationship and the communication network architecture connection relationship were studied,and the two-dimensional poor time distribution or three-dimensional distribution and other implementation methods were explored.CDN was constructed to construct the content edge node,and the core network,wireless network,bearer network architecture and network element deployment were optimized.And space-based network such as satellite was considered to introduce to build a scale-free small hop network on the existing communication network to achieve matching of network architecture and content distribution.  
      关键词:future architecture of communication network;mobile core network;IP network;scale-free network   
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    • Realization of vOLT and development trend

      Fengchao FU, Peng WANG, Yu MAO, Yongmei HUANG, Xiaobing GAO, Aihua ZHANG, Guoqiang LIN
      Vol. 34, Issue 7, Pages: 157-161(2018) DOI: 10.11959/j.issn.1000-0801.2018207
      摘要:SDN technology,NFV technology and cloud computing technology have been studied widely recently.How to realize vOLT based on these three techniques mentioned above was studied in order to solve theproblems that the OLTs of traditional PON faced,such as the OLTs of the PON were too difficultto operate and maintain,the resources allocation including ports,VLAN,MAC and others were not flexible,and theservice provisioning process was complicated.Four vOLT schemes were proposed.From the perspectiveof telecom operators,these four methods were compared and analyzed from the perspectives of application scenariosand the difficulty of introduction.Finally,the evolution route and the development trend of vOLT were conclued.  
      关键词:broadband access network;virtualized optical line terminal;software defined networking;network function virtualization;virtualization   
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    • Core network evolution planning oriented 5G

      Xu YANG, Ziyu XIAO, Yongping SHAO, Xiaoming SONG
      Vol. 34, Issue 7, Pages: 162-170(2018) DOI: 10.11959/j.issn.1000-0801.2018210
      摘要:Firstly,the 5G standard and industrial progress were summarized,and the 5G core network architecture,key technologies and interworking architecture were combed.On this basis,the idea of phased evolution planning and deployment suggestions for the 5G core network were proposed to provide reference for the introduction of the 5G core network in the present network.  
      关键词:5G core network;5GC;EPC;evolution;option   
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    • Dong WANG, Guochun LI, Xuehao YU, Zhiyu CHEN, Bingyu GE, Lei XIE, Jing TAN
      Vol. 34, Issue 7, Pages: 171-178(2018) DOI: 10.11959/j.issn.1000-0801.2018156
      摘要:With the increasingly serious environment of network space security,the importance of cryptography is becoming more and more prominent.There are many problems in the current application of cryptographic technology and the demand of secure and controllable password resource for key information structure is urgent.According to technology advantages and disadvantages of classical and quantum passwords were analyzed and the integration direction of quantum cryptography and classical password technology was proposed.At the same time,by giving full consideration to the development trend of cloud computing architecture,the password cloud service concept was proposed and the domestic password service cloud platform based on quantum secret communication was designed.It has positive guiding significance for building a new firewall of cyber security based on quantum secret communication.  
      关键词:quantum secret communication;quantum cryptography;domestic password;password service cloud;key distribution   
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    • Research on configuration of telecom pricing package

      Na CHEN, Lei LI, Senmao WEN
      Vol. 34, Issue 7, Pages: 179-186(2018) DOI: 10.11959/j.issn.1000-0801.2018105
      摘要:In response to the long period of manual configuration and low efficiency of telecom tariff,a templated tariff configuration system was proposed,which adopted predefined tariff templates and automated loading method for business parameters to improve the efficiency of tariff configuration.The group-level intensive sales products were verified,and other configuration contents of telecom tariff were extended.  
      关键词:telecom tariff;tariff configuration;template   
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    • Research and application of broadband speed-up technology based on IPTV

      Honggang ZHAO, Chunhui SONG, Dongsheng LIAN
      Vol. 34, Issue 7, Pages: 187-194(2018) DOI: 10.11959/j.issn.1000-0801.2018138
      摘要:With the increasing competition of broadband business homogenization and the explosive growth of IPTV users,differentiated products and service promotion are particularly important in the market competition.The development of IPTV industry and the technology of broadband speed-up technology was introduced,the core business process of broadband speed technology based on IPTV was expounded.Research results show that IPTV-based broadband speed-up technology can provide users with convenient and dynamic bandwidth adjustment services to meet the requirements of broadband bandwidth and IPTV users’ personalized bandwidth,the differentiation service advantage can be established,the risk of losing customers was reduced,the value of broadband and IPTV users is promoted.  
      关键词:internet protocol television;broadband speed-up;application of broadband speed-up   
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    • Zheng DONG, Ying ZHU, Chunze YANG
      Vol. 34, Issue 7, Pages: 195-200(2018) DOI: 10.11959/j.issn.1000-0801.2018158
      摘要:For achieving the requirement of real-time video monitoring which is located in the circuit cut-over operating point of the substation of the National Grid Nanjing Branch,China Telecom Nanjing Branch developed a new real-time video monitoring system which was based on internet of things technology and 4G wireless transmission network,by creating a smart pipeline based on 4G VPDN (virtual private dial-up network).The new system has solved the problem that the cable can not be used due to the frequent changing of the circuit cut-over operating points of the substation.  
      关键词:Internet of things;4G;LTE;VPDN;real time video monitoring system;substation   
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