• Title/Summary/Keyword: communication networks

Search Result 5,470, Processing Time 0.029 seconds

Analyses of Middleware Requirement for Home Network Security (홈 네트워크 보안을 위한 미들웨어 요구 분석)

  • 김정태
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.8 no.4
    • /
    • pp.861-865
    • /
    • 2004
  • Home computers that are connected to the Internet are under attack and need to be secured. That process is relatively well understood, even though we do not have perfect solutions today and probably never will. Meanwhile, however, the home computing environment is evolving into a home network of multiple devices, which will also need to be secured. We have little experience with these new home networks and much research needs to be done in this area. This paper gives a view of the requirements and some of the techniques available for securing home network.

A Study on the SCM Process in e-Trade (e-Trade의 SCM Process에 관한 연구)

  • 김명호
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.8 no.4
    • /
    • pp.918-925
    • /
    • 2004
  • SCM means that production companies set up schedules for the purchase, manufacture and sales of production parts, go on smoothly the flow of products (added value and material flow) by systematically arranging the demand plans of customers and the distribution situation, thereby executing the management of them in an effective way. This article aims at analyzing the external flow between government and companies and presenting the problems and the improvement plans, which can make clear all the information flow of supply networks including the internal integration.

Mitigation of Adverse Effects of Malicious Users on Cooperative Spectrum Sensing by Using Hausdorff Distance in Cognitive Radio Networks

  • Khan, Muhammad Sajjad;Koo, Insoo
    • Journal of information and communication convergence engineering
    • /
    • v.13 no.2
    • /
    • pp.74-80
    • /
    • 2015
  • In cognitive radios, spectrum sensing plays an important role in accurately detecting the presence or absence of a licensed user. However, the intervention of malicious users (MUs) degrades the performance of spectrum sensing. Such users manipulate the local results and send falsified data to the data fusion center; this process is called spectrum sensing data falsification (SSDF). Thus, MUs degrade the spectrum sensing performance and increase uncertainty issues. In this paper, we propose a method based on the Hausdorff distance and a similarity measure matrix to measure the difference between the normal user evidence and the malicious user evidence. In addition, we use the Dempster-Shafer theory to combine the sets of evidence from each normal user evidence. We compare the proposed method with the k-means and Jaccard distance methods for malicious user detection. Simulation results show that the proposed method is effective against an SSDF attack.

A New Estimation Model for Wireless Sensor Networks Based on the Spatial-Temporal Correlation Analysis

  • Ren, Xiaojun;Sug, HyonTai;Lee, HoonJae
    • Journal of information and communication convergence engineering
    • /
    • v.13 no.2
    • /
    • pp.105-112
    • /
    • 2015
  • The estimation of missing sensor values is an important problem in sensor network applications, but the existing approaches have some limitations, such as the limitations of application scope and estimation accuracy. Therefore, in this paper, we propose a new estimation model based on a spatial-temporal correlation analysis (STCAM). STCAM can make full use of spatial and temporal correlations and can recognize whether the sensor parameters have a spatial correlation or a temporal correlation, and whether the missing sensor data are continuous. According to the recognition results, STCAM can choose one of the most suitable algorithms from among linear interpolation algorithm of temporal correlation analysis (TCA-LI), multiple regression algorithm of temporal correlation analysis (TCA-MR), spatial correlation analysis (SCA), spatial-temporal correlation analysis (STCA) to estimate the missing sensor data. STCAM was evaluated over Intel lab dataset and a traffic dataset, and the simulation experiment results show that STCAM has good estimation accuracy.

A Modified FCM for Nonlinear Blind Channel Equalization using RBF Networks

  • Han, Soo-Whan
    • Journal of information and communication convergence engineering
    • /
    • v.5 no.1
    • /
    • pp.35-41
    • /
    • 2007
  • In this paper, a modified Fuzzy C-Means (MFCM) algorithm is presented for nonlinear blind channel equalization. The proposed MFCM searches the optimal channel output states of a nonlinear channel, based on the Bayesian likelihood fitness function instead of a conventional Euclidean distance measure. In its searching procedure, all of the possible desired channel states are constructed with the elements of estimated channel output states. The desired state with the maximum Bayesian fitness is selected and placed at the center of a Radial Basis Function (RBF) equalizer to reconstruct transmitted symbols. In the simulations, binary signals are generated at random with Gaussian noise. The performance of the proposed method is compared with that of a hybrid genetic algorithm (GA merged with simulated annealing (SA): GASA), and the relatively high accuracy and fast searching speed are achieved.

A Reconfiguration Technique of Logical Topology in a Ship Backbone Network (선박 백본 네트워크의 논리 토폴로지 재구성 기법)

  • Tak, Sung-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.16 no.5
    • /
    • pp.922-931
    • /
    • 2012
  • This paper studies a series of logical topology reconfiguration processes corresponding to a series of traffic demand changes in a ship backbone network. The proposed reconfiguration technique is to minimize costly changes of traffic forwarding paths and minimize the average hop distance of traffic forwarding paths in terms of ship backbone network performance simultaneously. Performance evaluation is conducted to illustrate the efficiency of the proposed reconfiguration technique. It shows that the proposed reconfiguration technique yields efficient performance in the entire series of reconfiguration processes.

Analysis of Anti-SPAM Regulations in Korean IT Law (정보통신망법 스팸 규제 개선 방안 연구)

  • Kim, Seongjun;Kim, Beomsoo
    • Journal of Information Technology Services
    • /
    • v.10 no.1
    • /
    • pp.21-34
    • /
    • 2011
  • Spam refers to any unwanted or unauthorized commercial messages. Spam may violate individuals' privacy or other personal rights. Spam often overloads network traffic, wastes individuals' time, lowers productivity and quality of life, and limits the trustworthiness of Internet businesses. As the use of mobile messaging services and social networking services both on mobile communication networks and on the Internet increase, newer and more complex types of IT applications and services are often used as new means of spam. In this research, the characteristics and impact of new and future forms of spam, and anti-spam related policies and regulations are surveyed. To improve the effectiveness of anti-spam policies and regulations in Korea, adding a definition of spam in the law, changing policies to focus on the 'type of services' rather on the medium of transmission, and redefining the scope of 'commercial purposes' in Korean law are suggested.

Recurrent Neural Network Adaptive Equalizers Based on Data Communication

  • Jiang, Hongrui;Kwak, Kyung-Sup
    • Journal of Communications and Networks
    • /
    • v.5 no.1
    • /
    • pp.7-18
    • /
    • 2003
  • In this paper, a decision feedback recurrent neural network equalizer and a modified real time recurrent learning algorithm are proposed, and an adaptive adjusting of the learning step is also brought forward. Then, a complex case is considered. A decision feedback complex recurrent neural network equalizer and a modified complex real time recurrent learning algorithm are proposed. Moreover, weights of decision feedback recurrent neural network equalizer under burst-interference conditions are analyzed, and two anti-burst-interference algorithms to prevent equalizer from out of working are presented, which are applied to both real and complex cases. The performance of the recurrent neural network equalizer is analyzed based on numerical results.

Micro-mobility Management Scheme Using Link-layer Information in the Wireless Internet (무선 인터넷 망에서 링크 계층 정보를 이용한 마이크로 이동성 관리 기법)

  • 정상환;김도현;조유제
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.28 no.6B
    • /
    • pp.563-572
    • /
    • 2003
  • When the Mobile IP is applied for mobility management protocol in the next-generation mobile communication networks, it can cause a serious performance degradation called micro-mobility problem. In this paper, we propose ANMM(Access Network Mobility Management) to efficiently support micro-mobility in the IP-based wireless access network. The ANMM scheme can reduce the handoff latency and signaling overhead resulting in performance enhancement by managing the mobility of mobile nodes within access network.

Optimal Waveform Design for Ultra-Wideband Communication Based on Gaussian Derivatives

  • Guo, Yong
    • Journal of Communications and Networks
    • /
    • v.10 no.4
    • /
    • pp.451-454
    • /
    • 2008
  • Ultra-wideband (UWB) radios have attracted great interest for their potential application in short-range high-data-rate wireless communications. High received signal to noise ratio and compliance with the Federal Communications Commissions (FCC) spectral mask call for judicious design of UWB pulse shapers. In this paper, even and odd order derivatives of Gaussian pulse are used respectively as base waveforms to produce two synthesized pulses. Our method can realize high efficiency of spectral utilization in terms of normalized effective signal power (NESP). The waveform design problem can be converted into linear programming problem, which can be efficiently solved. The waveform based on even order derivatives is orthogonal to the one based on odd order derivatives.