Please wait a minute...

Current Issue

    25 September 2014, Volume 35 Issue 9
    PaperⅠ Network attack and Prevention
    Research on security of third-party tracking
    Yu-qing ZHANG,Qian-ru WU,Qi-xu LIU,Ying DONG
    2014, 35(9):  1-11.  doi:10.3969/j.issn.1000-436x.2014.09.001
    Asbtract ( 259 )   HTML ( 7)   PDF (1199KB) ( 1187 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Third-party tracking can record users' behaviors across many websites.Increasing attention has been paid to the area of third-party tracking due to the fact that user's privacy protection is causing wider concern.The basic concept and present development were introduced.And security risks were also summarized.Then main technology of third-party tracking was intrduced from stateful tracking and stateless tracking aspects.Furthermore,several existing defenses of third-party tracking were described and compared.Finally,some hot research topics were given and the future research directions were discussed.

    Automated polymorphic worm signature generation approach based on seed-extending
    Jie WANG,Xiao-xian HE
    2014, 35(9):  12-19.  doi:10.3969/j.issn.1000-436x.2014.09.002
    Asbtract ( 260 )   HTML ( 0)   PDF (501KB) ( 332 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    A polymorphic worm signature generation approach based on seed-extending,SESG,was proposed.Firstly,algorithm SESG puts all sequences into a queue based on their weight.Seed sequence in the queue is extended,and all kinds of worm sequences and noise sequences are classified.Finally,worm signature is generated from classified worm sequences.Experiments are run to test SESG and compared with other approaches.Experiment results show that SESG can classify worm sequences and noise sequences from suspicious flow pool over other existed approaches,which can generate effective worm signature more easily.

    Exploit detection based on illegal control flow transfers identification
    Ming-hua WANG,Ling-yun YING,Deng-guo FENG
    2014, 35(9):  20-31.  doi:10.3969/j.issn.1000-436x.2014.09.003
    Asbtract ( 374 )   HTML ( 13)   PDF (715KB) ( 1442 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    In order to deal with exploit attacks such as APT,an approach was proposed to detect exploits based on illegal control flow transfers identification.Both static and dynamic analysis methods were performed to construct the CFSO (control flow safety outline),which was used to restrict the targets of control flow transfers occurred during the target program's running.When a call/ret/jmp was about to execute,the target was checked according to the CFSO.The illegal control flow transfer is considered as an exploit attack and all the following attacking steps could be captured.The ex-periment also showed that proposed method had decent overhead and could be applied to detect exploits online.

    Light-weight self-learning approach for URL classification
    Hong-zhou SHA,Zhou ZHOU,Qing-yun LIU,Peng QIN
    2014, 35(9):  32-39.  doi:10.3969/j.issn.1000-436x.2014.09.004
    Asbtract ( 268 )   HTML ( 1)   PDF (952KB) ( 724 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    A self-learning light-wight (SLW) is proposed.SLW is the first to introduce access relations and have the char-acteristics of feedback and self-learning.SLW approach starts from the seed set which includes known malicious pages.Then,it automatically figures out users with low credibility based on the seed set and the visit relation database.Finally,the access records of these users are used to identify other malicious pages.Experimental results indicate that SLW ap-proach can significantly improve the efficiency of malicious pages detection and reduce the average detection time com-pared with other conventional methods.

    Attacks on Telex Internet anticensorship system
    Long-hai LI,Cheng-qiang HUANG,Wan-xing WANG,Jian-jun MU
    2014, 35(9):  40-56.  doi:10.3969/j.issn.1000-436x.2014.09.005
    Asbtract ( 496 )   HTML ( 10)   PDF (2420KB) ( 727 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    As a typical router-redirecting based anticensorship system,Telex poses new challenges for Internet censors.To help common users evade Internet censorship,Telex employs network routers,rather than end-hosts,to relay network traffics to blocked destinations.The security of Telex from the censors' perspective is analyzed,and two kinds of active attacks aiming to break users' privacy are presented.The first is a kind of DoS attack,which exploits a security flaw of Telex handshake protocol.It can probabilistically identify the users who are using Telex,as well as break the availability of Telex.An improved handshake protocol to remedy the flaw is also proposed.The second is called TCP packets by-passing attack.Under that attacking scenario,censors make a small fraction of TCP packets from clients bypass the router and reach the cover site directly through asymmetric routing paths or IP tunnels,then determine whether a user is utiliz-ing Telex by observing the reaction of upstream traffic.The feasibility of bypassing attack has been testified by a series of experiments in a prototype environment.The bypassing attack is also applicable to other router-redirecting based anti-censorship systems.

    PaperⅡ
    Service substitution method based on composition context
    Hai-yan WANG,Si-rui LI
    2014, 35(9):  57-66.  doi:10.3969/j.issn.1000-436x.2014.09.006
    Asbtract ( 255 )   HTML ( 0)   PDF (1500KB) ( 564 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    With the variety of requirements from service requesters and the increasing complexity of network environ-ments,service composition has become more and more complicated.In order to decrease redundant information of the substituted service and improve the accuracy of service substitution,the composition context was regarded as the match-ing criteria and tried to substitute failed service with the following two steps.First,a composition context information collecting algorithm (CCICA) was proposed based on the color petri net model of the service workflow,and regarded the composition context as the collecting source of service information.Second,a levenshtein distance-based service substi-tution method (LDBSSM) was given,which was integrated with dependencies between service interfaces.Simulation re-sults show that the proposed LDBSSM method is practical because it can not only reduce redundancy of substituted ser-vice information but also effectively improve the accuracy of service substitution.

    Vertical handoff decision algorithm for cooperation of multi-terminal based on fuzzy logic terminal
    Gong-ye REN,Ji-hong ZHAO,Hua QU
    2014, 35(9):  67-78.  doi:10.3969/j.issn.1000-436x.2014.09.007
    Asbtract ( 263 )   HTML ( 4)   PDF (1911KB) ( 676 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    In order to solve the problem of vertical handoff decision for cooperation of multi-terminal,a fuzzy logic and AHP (analytic hierarchy process) based vertical handoff decision algorithm was proposed,which included the decision of the moment of triggering handoff and the construction of virtual terminal.Firstly,fuzzy logic was applied to decide the moment of triggering handoff.Secondly,a method combining AHP and SAW (simple additive weight) was used to choose the best composition manner of virtual terminal.Simulation results show that the proposed algorithm reduces the number of handoffs and the ratio of unnecessary handoffs.Additionally,it reflects application requirements and user preferences clearly.

    Virtual resource allocation method with the consideration of performance interference among virtual machines
    Lei YANG,He-xu XING,Yu DAI,Sai XU,Hao WANG,Bin ZHANG
    2014, 35(9):  79-90.  doi:10.3969/j.issn.1000-436x.2014.09.008
    Asbtract ( 308 )   HTML ( 3)   PDF (1074KB) ( 503 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    A method for allocating the virtual resource with the consideration of the performance interference among vir-tual machines was proposed.The model for evaluating the performance interference among virtual machines was formed and the method for predicting the performance interference was presented based on the workload pattern of the virtual machine.The predicted result of the performance interference among virtual machines was put into the evaluation of the resource allocation plan to be used as the basis for resource allocation.By doing this,the effectiveness of the resource al-location plan could be insured.The experiments show that the proposed virtual resource allocation method can insure the execution performance of the application deployed on the virtual machines.

    Time-varying channel estimation for LTE uplink SC-FDMA system with multi-user
    Li-hua YANG,Long-xiang YANG,Hong-bo ZHU
    2014, 35(9):  91-98.  doi:10.3969/j.issn.1000-436x.2014.09.009
    Asbtract ( 431 )   HTML ( 3)   PDF (2089KB) ( 864 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    A novel transform-domain based time-varying channel estimation method is proposed for the long term evolu-tion (LTE) uplink single carrier-frequency division multiple access (SC-FDMA) systems with multi-user.In the transform domain,the channel parameters of the two block pilots were firstly estimated,then the decision-directed (DD) based non-linear interpolation method was employed to estimate the channel parameters of the data symbols.To convenient equalization in the frequency domain,the transform expression of the transform-domain channel and frequency-domain channel was derived,by which the channel estimation in the frequency domain could be directly obtained.Simulation re-sults show that the performance of the proposed method is much better than those of the available methods,and the pro-posed method has a low computational complexity.

    Scheme on user identity attribute preserving based on ring signcryption for cloud computing
    Shuan-bao LI,Jian-ming FU,Huan-guo ZHANG,Jing CHEN,Jing WANG,Bi-jun REN
    2014, 35(9):  99-111.  doi:10.3969/j.issn.1000-436x.2014.09.010
    Asbtract ( 275 )   HTML ( 2)   PDF (1689KB) ( 956 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Identity attribute leak as the most severe security threat of cloud computing,in order to solve this problem,a protection scheme of identity attributes based on ring signcryption was proposed.Focused on digital identity management in cloud service,which discusses user key parting management with decentralization.Users can choose some seeds for generation and storage of key,then integrated user key cannot be acquired by registrar,based on this payload on certifica-tion management is reduced.In addition,access-centric blindness ring signcryption verification for identity attribute is designed,which constitutes ring of users and CSP,combined with own attribute users can accomplish ring-oriented sub-linear blindness signcryption and non-interactive public ciphertext verifiability for messages so that integrity and confidentiality of identity attribute can be protected avoiding identity attribute leakage in collusion of multi-CSP.At last,strong blindness and unforgeability of ciphertext and attribute is proved in proposed model,three private key components can be generated by users and identity forgeability of ring member can be prevented successfully on the condition of DBDH difficult assumption and adaptive chosen-ciphertex tattacking.Effectiveness of proposed mechanism is verified via performance evaluation of blindness ring signcryption algorithm based on comprehensive payload in identity attribute protection,and optimization is confirmed compared with similar algorithms.

    Hidden Markov model fused with staying time for personalized recommendation
    Sheng-zong LIU,Xiao-ping FAN,Zhi-fang LIAO,Jia HU
    2014, 35(9):  112-121.  doi:10.3969/j.issn.1000-436x.2014.09.011
    Asbtract ( 274 )   HTML ( 3)   PDF (1314KB) ( 994 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Static model in the recommendation system often regards the user's interest as changeless,which is inconsis-tent with the actual to a certain extent.With regards to this,a hidden Markov model fused with staying time for personal-ized recommendation (ctqHMM) based on the HMM dynamic model is proposed.The proposed model employs the transfer of the implicit state variables to simulate the changes of Web users' interests,and uses staying time to describe the level of interest to the specific preference and the importance of the recommended pages.Then,a user's clustering method based on the stationary distribution of the ctqHMM is also proposed and applied into the recommending systems.Experiment results on real Web server access log data show the encouraging performance of the proposed method over the state-of-the-arts.

    Energy efficient resource allocation scheme for AF relay downlink system
    Yu CHEN,Xu-ming FANG,Bo HUANG
    2014, 35(9):  122-132.  doi:10.3969/j.issn.1000-436x.2014.09.012
    Asbtract ( 222 )   HTML ( 0)   PDF (1984KB) ( 501 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    In order to maximize the total energy efficiency of amplify-and-forward relay downlink system,a joint scheme of relay selection and power allocation was proposed with the circuit power of the system.For reducing the computa-tional complexity,a step-by-step suboptimal allocation scheme was provided.Firstly,the virtual direct channel gains were adopted to select appropriate transmission link.Meanwhile,relay system was converted to the single hop system.Then,the power allocation could be solved by convex optimization.Besides,in order to accommodate different user distribu-tions,a resource allocation scheme based on cell zooming was also proposed.Simulations demonstrated that the solution of the proposed suboptimal scheme approaches the optimal solution.Additionally,the scheme with cell zooming is adaptable to different user distributions and further improves the total system energy efficiency.

    Coverage compensation algorithm based on vector algebra in hybrid wireless sensor networks
    Ning-ning QIN,Li-xia GUO,Bao-guo XU
    2014, 35(9):  133-139.  doi:10.3969/j.issn.1000-436x.2014.09.013
    Asbtract ( 182 )   HTML ( 0)   PDF (1726KB) ( 401 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Aiming at the phenomenon that coverage holes caused by energy depletion coexisted with remaining energy of dormant redundant nodes in hybrid wireless sensor networks(WSN),a coverage compensation algorithm based on vector algebra to repair coverage hole with redundant nodes was presented.This algorithm included both the respective dis-placement amount calculation method of all the redundant nodes which may be involved in compensation and policies of the choice of the best redundant nodes that were selected by hole boundary node on the basis of balancing the remaining energy of nodes.The result shows that this algorithm makes full of energy resources in the premise of complete coverage to repair coverage hole,and has a better performance in both movement distance and movement cost compared with ex-isting COA algorithm.

    Pilot based channel estimation in amplify-and-forward MIMO relay networks
    Jian ZHOU,Bao-yu ZHENG
    2014, 35(9):  140-146.  doi:10.3969/j.issn.1000-436x.2014.09.014
    Asbtract ( 200 )   HTML ( 3)   PDF (1208KB) ( 647 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    A channel estimation method in two time slots for two-hop amplify-and-forward MIMO relay channels is pro-posed.An algorithm for computing the optimal pair of source pilot and relay amplify matrix is developed,which mini-mizes the mean square error of the source-to-relay channel estimation subject to both power constraints at the source and the relay.The signal matrices are decomposed into unitary components and diagonal components.Then the bisection method is used to obtain the optimal diagonal components of the source pilot and the relay amplified matrix.The simula-tion results show that the proposed method has no ambiguity in the channel estimates.The effects of the channel correla-tion and the number of antennas on the performance of channel estimation are also analyed.

    Connectivity on fixed air route in aeronautical ad hoc networks
    Chang-yuan LUO,Yu-long SONG,Zhan-zhan GAO
    2014, 35(9):  147-155.  doi:10.3969/j.issn.1000-436x.2014.09.015
    Asbtract ( 296 )   HTML ( 2)   PDF (2014KB) ( 467 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Connectivity is the premise and foundation of networking and routing.Researches on fixed air route connec-tivity in aeronautical ad hoc networks are inadequate at present.Aiming at this situation,a method of connectivity re-searching was introduced.By combining characteristics of realistic layered with two-way air routes,and building the air-craft distribution as well as flight route models,the method deduced a math expression of one-dimensional route connec-tivity.Based on the above,probability figure was used to study on the network connectivity in view of probability matrix,and the correctness of the results were proved by experiments.Then,according to the practical flight data,the connec-tivity of one-dimensional route and network in Chinese partial airspaces was simulated; indicating that aeronautical ad hoc networks in the mentioned airspaces are feasible.Finally,some reasonable advises are given to improve the connec-tivity in four aspects,such as flight arrangement,planning and so on.

    Loop interference suppression based on space projection in full-duplex MIMO relays
    Ji-song YANG,Hao LIU,Chen SUN
    2014, 35(9):  156-163.  doi:10.3969/j.issn.1000-436x.2014.09.016
    Asbtract ( 242 )   HTML ( 2)   PDF (1253KB) ( 476 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    The system model including base station,full duplex MIMO relay and user station was established,and then obtained the loop interference matrix.While the case that loop interference signal's maximum multipath delay was greater than the symbol period was taken into account,signal space projection filters were designed to suppress the loop interference according to the space expanded by loop feedback interference matrix.Confronted the loop interference ma-trix full rank or not,filter design was based on subspace projection or null space projection algorithm.It was discussed that the projection algorithm how to influence the residual interference signal and the bit error rate of the relay station.Theoretical analysis and simulation results prove that the proposed space projection algorithm has ideal effect on sup-pressing loop interference.

    Overview
    Advance of performance modeling for Turbo receivers
    Yun XUE,Bin JIANG,Xi-qi GAO
    2014, 35(9):  164-174.  doi:10.3969/j.issn.1000-436x.2014.09.017
    Asbtract ( 214 )   HTML ( 4)   PDF (1499KB) ( 847 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Aiming at the performance modeling for Turbo receivers,the research results are summarized,in the mean-while,the characteristics and future trends are concluded in terms of equivalent model,transitive parameter,performance abstraction and transitive relation.The Gaussian distribution of equivalent model for log-likelihood ratiois the founda-tionof performance modeling research.Representative methods for application scenarios such as performance analysis,performance optimization and joint design with link are to derive the transfer chart with mutual information as transitive parameter,to derive semi-analytical transitive relation with bit error rate or fidelity as transitive parameterand to derive semi-analytical transitive relation with mutual information as transitive parameter,respectively.These methods represent the development direction of performance modeling for turbo receivers.

    Academic communication
    QoE utility function-based cross-layer resource allocation in multi-user MIMO-OFDM systems
    Da-ming WANG,Song CHEN,Wei-jia CUI,Qiang WANG
    2014, 35(9):  175-183.  doi:10.3969/j.issn.1000-436x.2014.09.018
    Asbtract ( 290 )   HTML ( 3)   PDF (829KB) ( 849 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Resource allocation problem was investigated for downlink multi-user MIMO-OFDM systems.A QoE (quality of experience) utility function was given according to the characteristics of real-time (RT) and non real-time (NRT) ser-vices,and then a RT & NRT QoE utility function-based cross-layer resource allocation algorithm was proposed.The al-gorithm firstly used the designed utility function to calculate the delta QoE,which was offered by users got resource.Secondly,it classified users according to their delta QoE and then allocated time-frequency blocks.Thirdly,it optimized the power allocation result by implementing pseudo water flooding power allocation.Simulation results show that com-pared with the existing algorithm,the proposed algorithm is better in the user average QoE,average packet delay to real time services,average packet lost rate to non real time services as well as sum throughput of system.

    Similar handwritten Chinese character recognition based on deep neural networks with big data
    Zhao YANG,Da-peng TAO,Shu-ye ZHANG,Lian-wen JIN
    2014, 35(9):  184-189.  doi:10.3969/j.issn.1000-436x.2014.09.019
    Asbtract ( 432 )   HTML ( 15)   PDF (853KB) ( 744 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    The recognition rates of the traditional similar handwritten Chinese character recognition (SHCCR) systems are not very high due to the restriction of feature extraction methods.In order to improve the recognition accuracy,a new method based on deep neural networks (DNN) was proposed to learn effective features automatically and conduct recog-nition.The method of how to generate similar handwritten Chinese character sets was introduced.The architecture of the DNN for SHCCR was presented.The performances with respect to different training data scale was compared.The ex-perimental results show that,DNN can learn features automatically and efficiently.The proposed DNN can achieve better performance comparing with support vector machine (SVM) and nearest neighbor classifier (1-NN) based on gradient features.Especially,with the increase of training data the recognition rate of DNN is improved observably,indicating that large training data is crucial for the performance of DNN.

    Pattern synthesis method for arbitrary arrays with desired mainloble response
    Dian-fei PAN,Nai-ping CHENG
    2014, 35(9):  190-196.  doi:10.3969/j.issn.1000-436x.2014.09.020
    Asbtract ( 283 )   HTML ( 1)   PDF (1713KB) ( 465 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    A pattern synthesis method based on adaptive array theory and convex optimization principle was proposed for arbitrary arrays,especially considering the influence of different orientation on array pattern.Firstly,the array pattern with special sideloble shape is obtained by adaptive array theory method; and then,the mainloble pointing to 0° is taken as reference to determine the pattern mainloble with variant steering angle.Finally,the optimal array pattern synthesis with desired mainloble response is converted to a second-order cone programming problem.The resulting optimization problem is nonconvex and is implemented via iterative algorithms of convex optimization,which can be solved using the second-order cone programming method at each iteration.Taking the method developed can obtain satisfied mainlobe response and less synthesized error in sideloble region.Theoretical analyses and simulation results show that the synthe-sized pattern has the same mainloble performance as the desired mainlabole in different orientation,and also the sideloble can maintain the shape to suppress the dynamic interference.

    Correction algorithm of migration through Doppler cells for space target in bistatic ISAR
    Bao-feng GUO,Chao-xuan SHANG,Xin WANG,Jun-tao MA,Jian DONG
    2014, 35(9):  197-206.  doi:10.3969/j.issn.1000-436x.2014.09.021
    Asbtract ( 264 )   HTML ( 2)   PDF (1694KB) ( 718 )   Knowledge map   
    Figures and Tables | References | Related Articles | Metrics

    Aiming at the problem of migration through Doppler cells in bistatic ISAR,based on bistatic ISAR turntable model,the reason of migration through Doppler cells from two aspects of echo model and the relative speed changes of scattered points was analyzed.The correction algorithm was presented based on range cell phase compensation.Firstly,target rotating rate was estimated through the geometrical relationship of bistatic stations and target.Secondly,the algo-rithm divided the echo data into two parts,and then imaging separately,getting two images of different angles of view.And the rotating center was estimated according to the maximum criterion of rotating correlation,which was used to range scaling.The migration through Doppler cells was corrected through phase compensation of each range cell at last.The simulation result show that the method could solve the problem of migration through Doppler cells,and could im-prove the image quality.

Copyright Information
Authorized by: China Association for Science and Technology
Sponsored by: China Institute of Communications
Editor-in-Chief: Zhang Ping
Associate Editor-in-Chief:
Zhang Yanchuan, Ma Jianfeng, Yang Zhen, Shen Lianfeng, Tao Xiaofeng, Liu Hualu
Editorial Director: Wu Nada, Zhao Li
Address: F2, Beiyang Chenguang Building, Shunbatiao No.1 Courtyard, Fengtai District, Beijing, China
Post: 100079
Tel: 010-53933889、53878169、
53859522、010-53878236
Email: xuebao@ptpress.com.cn
Email: txxb@bjxintong.com.cn
ISSN 1000-436X
CN 11-2102/TN
Visited
Total visitors:
Visitors of today:
Now online: