最新刊期
卷 32 ， 期 11 ， 2016
- 摘要：Micro service is a new method of modern application architecture,its characteristic is that decomposing the complex applications into discrete,independent service,so that decoupling of applications scheme can be achieved,and the individual service could be developed,deployed and extensioned independently.The change of the application must drive on the change of the underlying network,the architecture of reconfigurable fundamental information communication network aimd to compensate for the network business requirements and network transmission capacity through the network reconfiguration mechanism.A meta model construction mechanism with the SDN architecture for fusion the reconfiguration and software defined network technology was proposed,it aimed to present the services of each layer in the SDN architecture by the form of meta model.And after referencing the AKF scale cube,a kind of meta model building method based on orthogonal decomposition was proposed.Finally,the feasibility of meta model building method based on orthogonal decomposition from the theoretical analysis and development of example was verified.关键词：micro service;reconfigurable fundamental network;SDN;orthogonal decomposition875|1771|0更新时间：2024-06-05
- 摘要：Currently,most of the routing algorithms support only one QoS parameter,and do not consider the fairness of system scheduling service.Obviously,multi-parameters constrains problem is NP hard problem,it is impossible to solve this kind of problem by traditional routing algorithms.The routing thought from ant colony algorithm（ACO）was introduced.On the basis of the ACO,and combined with the business attributes of traffic flow,a new algorithm was put forward which introduced the delay and packet loss into the ACO,as a dependence of routing.In new algorithm,which according to the real-time status of network,the suitable routing was chosen for different types traffic and forward by multi-path base on the classification of traffic flows.The experiment shows that this algorithm can decrease the delay and packet loss effectively.关键词：SDN;business attribute;ACO;multi-path routing694|1034|0更新时间：2024-06-05
- 关键词：wireless mesh network;multi-input multi-output;channel allocation;objective optimization845|1290|0更新时间：2024-06-05
- 摘要：Through analyzing the access efficiency of machine type communication（MTC）devices in LTE-Advanced system,a loading-feedback control method was proposed.The current access load was estimated and the load of next access slot were calculated using the preamble state information,and the access control parameters for MTC device were adjusted based on the load change dynamically.The good performance of the proposed solution was evaluated by computer simulations.The simulation result shows that the proposed scheme can reduce the impact of nearly simultaneous access of a large number of MTC devices on human-to-human（H2H）devices,decrease the number of retransmissions and improve the access success rate effectively.关键词：LTE-Advanced;andom access;machine type communication;loading-feedback661|1045|0更新时间：2024-06-05
- 摘要：In order to improve the accuracy of predicting vehicle collision accidents and reduce the probability of collision accidents,vehicle anti-collision algorithm（VACA）based on vehicle to vehicle communication was proposed.According to Beidou location coordinates of vehicle itself and other vehicles in the vicinity,VACA used Kalman prediction algorithm to predict next vertical and horizontal locations of vehicles.VACA used data prejudge method to directly judge whether collision will happen.When it could't be directly judged,safe distance with variable acceleration was calculated,and collision state prediction model was established and solved,then minimum collision prediction time could be obtained.If the minimum time was less than threshold value,alarm signal would be sent to remind driver.Simulation results show that compared with IVCWM and ECWA,VACA can predict collision accident more accurately and has certain application value.关键词：vehicle to vehicle communication;anti-collision;Beidou localization,warning696|2747|0更新时间：2024-06-05
- 摘要：Focused on the low energy efficiency and short lifetime of underwater wireless sensor network（UWSN）,a load balanced and energy efficient underwater clustering（LBEEUC）protocol for UWSN was proposed.For cluster head settings,due to the consideration of load balanced,the proportion of cluster heads based on experience-load was set.The area with high experience-load could obtain more cluster heads than other areas to process data forwarding.And then,for intra-cluster communication,some relay nodes were set to save energy of long range data transmission between cluster head and nodes.Relay nodes also could be used to eliminate redundant information by advance data fusion.Finally,for inter-cluster routing,Q-learning algorithm was used to implement optimal path planning based on the criterion of least energy consuming.The simulation results demonstrate that the LBEEUC protocol can efficiently improve the energy utilization,prolong the network lifetime and balance the energy consumption of the network.关键词：underwater wireless sensor network;clustering;load balance;energy efficiency559|907|0更新时间：2024-06-05
- 摘要：In view of the problem that the universal filtered multi-carrier（UFMC）system is sensitive to carrier frequency offset,a frequency synchronization algorithm was proposed.For the sake of keeping good features of UFMC system and reducing the complexity of filter design,the algorithm designed a pilot sequence which sub-bands are orthogonal,and used the non-linear least square algorithm（NLS）to realize the frequency offset estimate.In order to further improve the performance of algorithm in low signal to noise power ratio（SNR）environment,the receiver could process data by constructing sequence and calculating the correlation of estimated signal.Simulation results demonstrate that the designed pilot is superior to all-one pilot in terms of both bit error rate（BER）and CFO performance over additive white Gaussian noise（AWGN）and rayleigh fading channel.And in low SNR environment,the improved algorithm has better performance than NLS algorithm under CFO.关键词：universal filtered multi-carrier;pilot design;non-linear least square algorithm;frequency offset estimation547|1661|0更新时间：2024-06-05
- 摘要：The existing DTN routing algorithms tend to make data transition inflexible and have a long delay in contact.To solve those problems,an algorithm was proposed which called meeting delay expect value in spray and forward routing algorithm for DTN（MDESF）.This algorithm will use mobile node's contact history to conduct the expected average contact/disconnect time and message expected wait value（EWV）.With those attributes the MDESF will proportionally distribute replicas of a message between two nodes in multiple replicas phase.A buffer management strategy was proposed in order to improve the success rate of imformation fornarded.The simulation results illustrate that the proposed MDESF protocol outperform other existing ones.关键词：delay tolerant network;spray and wait routing;buffer management strategy342|734|0更新时间：2024-06-05
- 摘要：Grey GM（1,1）prediction method is only suitable for the prediction model of the original sequence which satisfies the characteristic of the approximate exponential through the accumulated generating operation.In order to widen the application range of the traditional grey prediction model,a new method,dubbed DGM（1,1,c,β）model（direct grey model）,was proposed to improve the accuracy of grey GM（1,1）prediction by optimizing initial conditions.DGM（1,1,c,β）model was established for the original sequence conforming to the approximate exponential and the model parameters were obtained by the particle swarm optimization algorithm.Both the simulation and analysis of the example demonstrate that the proposed method is more effective and practical.关键词：grey GM（1,1）model;initial condition;PSO algorithm;DGM（1,1,c,β）model468|1181|0更新时间：2024-06-05
- 摘要：Wideband distributed cooperative spectrum sensing based on compressed sensing can not only reduce high sampling rate,but also improve the spectrum sensing performance in low signal to noise ratio environment.In order to further enhance the spectrum sensing performance,a wideband distributed cooperative compressed spectrum sensing algorithm based on weighted consensus optimization was proposed.In this algorithm,the next iterative reconstruction weights were determined according to the current iterative reconstructed spectrum signal,which can encourage the sub-band occupied by primary user to generate signal value and decrease the likelihood of incorrect reconstruction.Simulation results show that the proposed algorithm can not only increases the spectral reconstruction accuracy,but also reduces time and communication costs of the sensing process,and improves the spectrum sensing performance.关键词：wideband spectrum sensing;compressed sensing;distributed cooperation;weighted consensus optimization490|604|0更新时间：2024-06-05
- 摘要：Through the analysis of power line channel characteristics,the corresponding mathematical model was established,the multipath channel characteristics of power line were studied.Combined with a novel compressed sensing and processing technology,a channel estimation method of power line based on compressed sensing was proposed.The transmission characteristics of power line channel were analyzed.Taking advantage of its sparse,only a small amount of noise and channel parameters needed to be collected,extracted and stored,which greatly reduced the digital signal processing module of data processing,and the storage hardware requirements and hardware costs were reduced.关键词：power line communication;channel estimation;compressed sensing363|811|0更新时间：2024-06-05
- 摘要：The energy consumption and coverage is a fundamental problem in the field of wireless sensor networks,which is also a priority issue.Based on the isomorphism of the sensor nodes,an optimized coverage algorithm with controllable dynamic parameters（OCCDP）was presented.Firstly,it gave the solution of the largest seamless coverage probability under the joint coverage of three nodes.Secondly,it gave the solving method of the sensor nodes coverage quality expectation in monitoring area and compares to neighbor nodes coverage probability determination method.When there was a redundant coverage,it gave the process of calculation of coverage probability when any sensor node was in the condition of redundant nodes coverage.Finally,through the comparison of the simulation with other algorithms in terms of the coverage quality and the network lifetime,it can be concluded that the average performance can upgrad to 11.02% and 13.27%,which proves the effectiveness and feasibility of the algorithm.关键词：wireless sensor network;coverage quality;nodes joint;network lifetime;optimization coverage343|527|0更新时间：2024-06-05
- 摘要：A novel chaotic image encryption algorithm based on single image local scrambling and dynamic feedback diffusion was presented.Firstly,a single image local scrambling algorithm was proposed.Secondly,a novel dynamic feedback diffusion strategy was proposed to change the pixel values of the scrambled image in the phase of diffusion,by which improved the results of image encryption.Finally,the simulation results and performance analysis show that the number pixels change rate（NPCR）values and unified average changing intensity（UACI）values of the proposed algorithm can be close to 99.6% and 33.4%,showing that the proposed algorithm has better resistance to differential attacks and saves time compared with the other three classic algorithms.关键词：chaotic theory;image encryption;scrambling;dynamic feedback;diffusion446|1273|0更新时间：2024-06-05
- 摘要：The performance of power line communication systems is seriously affected by impulsive noise.The compressed sensing theory has been applied for estimation in view of the sparse property of impulsive noise in the time domain.A compressed sensing method based on the iterative hard thresholding was proposed to estimate the impulsive noise.Firstly,the thresholding value was updatedby iteration,and then the thresholding function was used to estimate the impulsive noise.Finally,the impulsive noise was cancelled by subtracting the estimation value from the received signal.Simulation results show that the proposed method can efficiently estimate the impulsive noise and promote the performance bothinmean square error and signal to noise ratio.关键词：power line communication;impulsive noise;compressed sensing;iterative hard thresholding407|825|0更新时间：2024-06-05
research and development
- 摘要：Cloud computing scale development provides a new chanllenge to data center network.Data center network is required virtulizing by SDN in order to meet flexible dynamic network requireement under multi-rent environment.SDN is the core technology to realize data center virtulization.The key technology of overlay SDN network virtualization was studied,the compatibility problems remained in commercial overlay SDN products was discussed,the main methods to solve this problem was analyzed,and finally an new overlay SDN architecture based on open source software and white-box switch that could work in heterogeneous hypervisors environment was proposed.关键词：overlay SDN;heterogeneous compatibility;white-box switch595|1812|0更新时间：2024-06-05
- 摘要：The traditional network architecture has some problems such as closed rigid structure,highly restricted data forwarding performance,and low utilization rate of resources,which can't meet the diverse services' requirements.In order to solve these problems,the concept of network slice was introduced.A novel network architecture for future mobile communication was proposed,which is based on network function virtualization（NFV）and software defined networking（SDN）.This new network architecture can provide personalized network services to users based on third-party needs,share and isolate of network resources,the cost of a large number of operators was saved in terms of infrastructure.关键词：SDN;NFV;network slice;architecture research1281|3868|0更新时间：2024-06-05
- 摘要：The dynamic feature of NFV demands that security technologies,policies,processes and practices were embedded in the genetic fabric of VNF.The VNF security management lifecycle represented the security processes spanning from VNF platform guidance,to VNF instantiation,operation and retirement.It was intended to represent a process view of VNF security and process guidance.关键词：NFV;VNF;lifecycle;security management405|1366|0更新时间：2024-06-05
- 摘要：Blockchain is one kind of collective and decentralized database technology without trust among the nodes.In essence,it is a distributed database which has no delete and update operations.The technical principles of blockchain was introduced,its industry situations and existing problems were discussed,and related policy suggestions were proposed from government,industry association and academic institution.关键词：blockchain;decentralization;Byzantine failure762|2543|0更新时间：2024-06-05
- 摘要：Based on the unique technical characteristics and existing equipment ability of the SDR base station,and the main problems in deploying SDR base station,faced with the network developing environment and operating conditions for operators,the main application scene of SDR base station was put forward,and the new ideas of using GL1800 to construct light-state network in city and county scene were discussed.关键词：software defined radio;multimode;hybrid network308|904|0更新时间：2024-06-05
- 摘要：Today,testing method of video conference system is mostly functional,and there is no good solution about performance testing,especially the maximum concurrent ability.The performance indicators are usually provided by manufacturer of system or based on the simulator of system manufacturer.The concurrent capability of video conference system affects the experience of customers.In order to give the objective performance indicators of video conference systems,especially the carrier-class ones,the testing and analysis method of concurrent ability were discussed,then a video conference system of one telecom operator was taken as an example,and the suggestions of testing concurrent ability of video conference system were given.关键词：carrier-class video conference system;application layer;maximum concurrent connection;maximum connections per second;testing and analysis method326|897|0更新时间：2024-06-05
- 摘要：With the boom of NFV technology,the traditional network hardware was being replaced.For telecom operators,NFV was expected to deploy on the universal server,which could reduce the CAPEX and OPEX,improve operational efficiency,achieve rapid deployment of new service,and ultimately increase the operator's revenue.However,NFV had its unique characteristics,which would consume a large amount of public IPv4 addresses if we used the same deployment and configuration as traditional network hardware in the scenarios of enterprise PPPoE dial-up network.NAT444 was introduced in NFV environment as a solution,including the deployment and traceability system.关键词：NFV;PPPoE;NAT444;spine-leaf;traceability436|804|0更新时间：2024-06-05
- 摘要：In view of the faults in traditional communication engineering design assessment,such as general indicators,the lack of quantitative analysis etc,the comprehensive evaluation system was constructed,which combined with the hierarchical analysis and fuzzy evaluation.In the basis of studying the existing model of communication engineering design evaluation and the demand for communication engineering project design of the social development,the evaluation index system was established firstly by designing questionnaire and analyzing the investigation results.According to the importance of the indicators,it determined the index weight by the analytic hierarchy process.Then fuzzy evaluation matrix was obtained by membership degree calculation,the two stage fuzzy comprehensive evaluation was completed in the excellence selecting of telecommunication engineering.关键词：telecommunication engineering design;index system;fuzzy evaluation356|601|0更新时间：2024-06-05
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