摘要:Name-based routing has become one of the hot topics in future network.However,due to the sustained growth of the size of nodes and information,the scalability issue is becoming one of the bottlenecks of name-based routing.As a new type of scalable routing,geometric routing provides both scalable routing tables and low routing paths,but it is difficult to support name-based routing.A universal scalable geometric routing scheme based on location-independent names(GRIN)was proposed.GRIN implemented a hybrid geometric routing(HGR)combining greedy routing with source routing,introduced a distributed name resolution using 2-level sloppy groups.Then the state and the path stretch upper bound of GRIN were analyzed.The simulation results show that GRIN guarantees scalability,low stretch and reliability.It outperformanced other similar routing schemes.
摘要:Green network is a hotspot in network research recent years,virtual network embedding(VNE)algorithm which focuses on saving energy,becomes very important in resource allocation in the network virtualization.A green VNE algorithm which applies swarm particle optimization(GVNE-PSO)was proposed,the evolution behaviors and parameters of each particle was redefined,and the number of nodes and links that could be switched off as the fitness function were considered,the optimum solution of green VNE in a low time complexity was achieved.The results show that compared to the exiting algorithm,it greatly reduced the time complexity offline,when online,it also raised the rate of virtual network acceptance,and the same with nodes and links that can be switched off,what's more,the performance period are shorter.
摘要:Cooperative transmission can effectively overcome performance degradation caused by channel fading and thus improve diversity effect.In order to improve the spectral efficiency of all-time cooperative,relay selection strategy with selective decode-and-forward protocol based on threshold decision was mainly investigated.The performance was also analysed and the approximate expression of the outage probability and the spectrum efficiency with high signal-to-noise(SNR)were derived.Simulation results show that under low-SNR and few relays circulations,the outage probability under different thresholds are very close.If the collaboration threshold increases by 0.09,the spectral efficiency improves by 0.12.Under high-SNR and many relays circulations,the spectral efficiency under different thresholds are similar.When the system outage probability is 10<sup>-2</sup>,the collaboration threshold decreases by 0.9 and 1.1 dB SNR gain can be obtained.
摘要:In order to solve the traffic explosion of indoor and hotspots,LTE-Hi was put forward by 3GPP organization in Release12.Due to the coverage particularity of indoor and hotspots scenarios,the organization introduced 256QAM to improve system performance.According to the 256QAM constellation given in the standard,a soft demodulation algorithm based on border distance decision was deduced.Through a simulation of the UE SINR distribution in the LTE-Hi scenario,the feasibility of the 256QAM was proved and according to the CQI/MCS/TBS signaling table changed for 256QAM,link level simulation showed the 256QAM and 64QAM throughput in comparison under different EVM index.Finally,the system performance with and without the introduction of 256QAM under different scenarios was evaluated.
摘要:Wideband spectrum sensing technology based on compressed sensing can effectively reduce the high sampling rate and the complexity of spectrum sensing.During the sensing process,in order to enhance the reconstruction performance of the spectrum signal,a modified OMP sub-band matching selection algorithm for wideband spectrum reconstruction based on the prior knowledge of boundary information and the block sparse characteristics of wideband frequency signal was proposed.This method can reduce the number of iterations in spectrum reconstruction with OMP algorithm and enhance stability of spectrum reconstruction.Simulation results show that the proposed method can not only improve the accuracy of spectrum reconstruction,but also effectively shorten spectrum sensing timeand achieve better wideband spectrum sensing performance.
摘要:Microblog is an important social network with rapid propagation speed and great influence.The network influence is determined by users' node characteristic.Nodes' degree and propagation model in microblog forwarding network were investgated.Firstly,microblog forwarding network was constructed through distinguishing information flow direction.Secondly,the mean and variance of out-degree and in-degree were discussed.The difference between out-degree and in-degree was clarified.Finally,the simulation shows that the direction characteristic of edge has significantly influence on information propagation.The propagation becomes harder and propagation range diminishes while percolation threshold rises in directed graph under the same probability.
摘要:The definition of the spectrum availability in terms of static spectrum,semi-static spectrum and dynamic spectrum and the definition of service requirement index based on M-LWDF QoS definition were proposed.A spectrum allocation method and a redistribution method combined with spectrum availability and subscriber requirement were presented.The main idea of the method is that subscriber requirement and availability of spectrum resource are quantified,and then spectrum resources are allocated to subscribers by a one-to-one mapping based on their quantified values in the same sequence.Compared with the random distribution scheme and the dynamic scheme following static allocation,simulation results show that the scheme presented can obviously improve system performance in average number of failure distribution and average total data rate.
摘要:Clustering analysis is an important and challenging research field in machine learning and data mining.A fast and effective clustering algorithm based on the idea of local density was proposed by Alex.But the number of clusters and cluster centers in the algorithm were determined by hand.Therefore,the candidates of cluster centers based on local density were firstly selected and then density connectivity method was used to optimize the candidates.The classes of samples are the same as the nearest center with bigger local density.Experiments show that the proposed method has a better cluster efficiency and can handle the problems of uncertain cluster number and cluster centers.
摘要:In order to promote the cooperation among the nodes which exist in dynamic and open peer-to-peer network,G-SLACER algorithm was provided by introducing pacesetter nodes.30% of network nodes were initialized to pacesetter nodes.In the process of topology reconstruction,a guided link to the most advantage node was added.To encourage studies between nodes,the payoff of the whole network was increased.The experimental results show that the G-SLACER algorithm has good generality for different sizes of networks,and it enhances the stability of CCP.Compared with other evolutionary game algorithms,cooperation state of P2P network formed by G-SLACER algorithm appears earlier and more stable.
摘要:The trusted measure model for communication was proposed by computing its value of security,control and survivability with continuous-time reward Markov method.The“state bomb”problem in traditional state analysis method was solved by the way of structural equation solution.The generic function optimization algorithm was used to reduce computational complexity.Simulation experiments show that the model is correct and feasible.
关键词:industrial control network;trusted network;network structure function;universal generating function;reward markov chain
摘要:Dispersion of the signal energy and the inter symbol interference(ISI)is caused by the multipath fading in 60GHz pulse communication environment.To solve this problem,the severity of the ISI in the system was analyzed,and the method to eliminate interference was studied.Based on the 60GHz wireless channel model established by IEEE 802.15.3c,the simulation platform of 60GHz pulse communication system was built.Theoretical analysis and numerical simulation of ISI in the system were carried out,and a receiver scheme of combining Rake receiver and equalizer was designed.Results show that,the two taps MRC-Rake receiver module combined with MMSE linear equalization module can not only improve the signal energy by multipath diversity,but also eliminate ISI.The performance of the system was improved without increasing the complexity.The scheme provides a reference for the design of 60GHz pulse communication system in the future.
关键词:60GHz;5G;inter symbol interference;equalizer;Rake receiver
摘要:As APT(advanced persistent threat)attacks are increasingly frequently,higher requirements for the detection of APT attacks were proposed.It was an effective method to early discover the attack behavior of APT based on homologous behavior analysis.Aiming at the problem of low efficiency of data authentication caused by excessive data,the historical behavior database with data label technology was established and the database was stored in the cloud.Relying on the Hadoop platform and the aggregate computing ability of MapReduce and the pseudorandom permutation technique,the whole traffic parallel detection of the network was realized.In order to determine whether there was a APT attack behavior,the detection of APT attacks was implemented by comparing the data labels in the database.Test results show that the proposed method can detect the abnormal behavior of APT from the network as soon as possibleand improve the efficiency of the whole data flow detection.
摘要:In OFDM system,the least square(LS)algorithm has the shortage of noise cancelling and interference suppressing.An utility channel estimation algorithm which took advantage of the time frequency characteristic in OFDM system was proposed.The new channel estimation algorithm realized noise cancelling and interference suppressing through time-frequency transform by three times.In view of time-frequency transform could be achieved by FFT/IFFT,the new channel estimation algorithm complexity was low.In the TU channel simulation,the new channel estimation algorithm has the high performance,which was 3 dB better than the LS algorithm.In the TU channel simulation with interference suppression,the new channel estimation algorithm has only 1.5 dB reduction in performance.
摘要:According to the irregular fluctuation of the armored target's detection signal with passive millimeter wave,an armored target's recognition method which the feature is entropy was proposed.Based on the measured data,the validity of this method was demonstrated.Through simulation,the antenna temperature curve of armored target,dry sand,steel and water was obtained respectively.Then,the entropy feature of each one was extracted.The histogram and the average value of the entropy were analyzed.The results show that when the entropy was used as the feature,the armored target from the background and typical“interferences”can be effectively recognized and practical engineering significance was obtained.
摘要:After years of development,the internet continues to penetrate the economic and social fields and it has become an important infrastructure of information society,bringing increasingly influence and changes to the service industry,manufacturing industry and other traditional industries.The concept of“internet +”gradually gets into people's hearts.Internet service system was established based on analysis of connotation of internet,integrating path and its law to manufacture were researched systematically from industrial chain,value chain and enterprise production activities.
摘要:First of all,the challenges of our country's economy and manufacturing industry were introduced.Secondly,the connotation of the integration of the two and the related concepts,such as intelligent manufacturing,the internet and industrial integration,were detailed presented,and finally suggestions on the implementation of the integration of the two were put forward.
关键词:two fusion;intelligent manufacturing;internet and industrial integration
摘要:Firstly,the organizational structure and positioning of German“Industrial 4 Platform”were introduced,and then the core research was focused on,such as research and innovation,reference system and standardization,network system security.Finally,we should draw on the advanced experience of German manufacturing field,and promote the development of intelligent manufacturing in China.
摘要:Based on the well designed resource information model,the telecom operators can effectively manage the telecom network resource.A resource modeling methodology was proposed.The modeling methodology was based on the network topology and the port.The modeling process was divided into seven sub-processes:network analysis,network node identification,connection identification,equipment description,ability description,space resource analysis and model expression.In addition,a discussion on the relationships between entities had been made.Based on the modeling methodology,the LTE resource information model was constructed.Therefore,the validity of the modeling methodology was proven.Moreover,the LTE resource information model was objectively evaluated through three aspects:the complexity of the class,the ratio of depth and width of the inheritance tree and the coupling degree between classes.Results show that this model is high-quality.
摘要:Device-to-Device(D2D)communication is an important technology in 5G network.It helps to improve the transmission efficiency of data dissemination services.However,due to the extra signaling overhead caused by D2D communications,currently most of enhanced-multicast solutions cannot solve the contradiction between high-efficient data transmission and low-efficient signaling procedure,so as to reduce the overall performance gain.An intra-cluster D2D information sharing algorithm based on matrix analysis which includes centralized and distributed modes was proposed.The proposed algorithm could significantly reduce D2D retransmission times in clusters by adaptively selecting the optimal transmitters and data packets for D2D multicast retransmission,achieving the aim of reducing signaling overhead and transmission delay.
摘要:Traditional datacenters have been heavily impacted due to the development and large-scale deployment of cloud computing technology.Co-deployment of SDN and NFV technology shows its distinct advantages of vitualizing network resources in the scenario of cloud datacenter.Resolution tests aiming at co-deployment of SDN and NFV have directive significance.According to the resolution test,SDN and NFV technology were matured already for the commercial deployment in operators' network.Further research needs to be focused on the key problems found out in scheme designing and the resolution test.
摘要:In the era of data technology,the higher requirements of telecom operators,such as business innovation and strong operation supporting,are being placed on data analysis system.Firstly,the requirement and challenge of the rising data analysis and the enhancing data value were expounded.Then,in order to realize open architecture and flexible operation support,the logical framework and technology architecture of the service-oriented data analysis system,as well as the data governance and the data security management were proposed.Finally,the service scenarios and the business value of the platform were introduced by an example.
摘要:For the use rate of international roaming communications products are too low,based on full volume data of mobile user in communication behavior and attribute,a method of combining statistical analysis and building recognition model was proposed.Using SPSS and Clementine tools,with high hit rate and wide coverage as the target,the user potential features of the international roaming communications products were extracted.Subsequently,the empirical analysis of the potential features also was given,and the very high accuracy rate was obtained.This has important reference value for operators to carry out international roaming service better.
摘要:Taking the cloud computing data center as the breakthrough point,firstly,the characteristics of overlay network,SDN controller and VxLAN in SDN field were presented.Secondly,two kinds of problems about general server performance and service chain were analyzed in NFV field.Finally,the early test progress of SDN/NFV technology and related conclusions were expounded,then VDC was discussed.
关键词:cloud data center;software defined networking;network function virtualization;VxLAN;big two-layer
摘要:With the implementation of“Broadband China”strategy,IP services become more and more diversified,the demand for all kinds of security is also increasing.The key technology of BRAS hot backup and its realization method were introduced,realizing the seamless handover between primary and standby BRAS and effectively controlled the route range in BRAS.The routing was optimized to reduce traffic between interconnect circuits of primary and backup BRAS to improve the utilization efficiency of the circuit.
摘要:The principles and advantages of intelligent DNS resolution were mainly analyzed.The carrier DNS's intelligent resolution was studied,such as the key intelligent resolution techniques of cache server,recursion server and cache view.According to the characteristics of huge telecom carrier's network,a solution of intelligent resolution,which can provide reference for the development and optimization of huge telecom carrier DNS was proposed.
关键词:domain name system;intelligent resolution;cache;recursion
摘要:In the background of new business requirements,the monitory point selection for new monitoring business,anti-spam system architecture,the function of the system need and the key points that should pay attention to system deployment were analyzed.Finally a set of two level monitoring system architecture and deployment guidelines for monitoring system were put forward.
摘要:User behavior information contains great value.Telecom operators must collect and deal with this information to create new business growth point.Through the research of information collection and processing,the implementation scheme of fast data application was given.Services such as user care and information push were provided based on the behavior of position change and voice calls.The application was used in the new business field of China Telecom and achieved remarkable results.
摘要:From the current development situation of SDN technology,characteristics of CMNet were analyzed.Then the CMNet evolution was divided into three stages:firstly,focused on the application of the key scenes in metro area; secondly,gradually expanded to the CMNet backbone network depended on the technology maturity and the perception of traffic engineering; thirdly,business analysis system,business system,third-party's system and other systems were linked to achieve the market adapting and stitchable SDN.
摘要:With the transition of the traditional data center to cloud data center,government and financial industry's information system disaster recovery and backup becomes an important means to ensure services continuity and data availability.Active-active data center can enhance system availability and improve the utilization of equipment,becoming the future trend of data center construction.Active-active data center involves networking,virtualization,storage technology.These related technologies to achieve active-active in the data center were described,and the effectiveness of the technology was verified by the implementation of the governmental data center.
摘要:With the rapid development of mobile internet,as well as the rapid expansion of the scale of 4G network,the frequency resources worldwide are increasingly scarce.Learning from the successful experience of the development of TD-LTE and LTE FDD fusion,the challenges faced by the development of the integration of networking strategy and TD-LTE international development were analyzed,the development mode and strategy of TDD and FDD were proposed,and the future development targeted recommendations of the communication operator network was put forward.The TD-LTE and LTE FDD convergence has become a big trend.As the strategic layout of the communications operators,4G network using LTE network approach,should be taken into account in the LTE master plan in advance.
摘要:The limitation of traditional smart pipe capabilities offering was focused,a new self-service network capabilities offering architecture based on the electronic warrant was proposed,including the main service flow,the key technical points and the test result of the current network.