• Title/Summary/Keyword: communication networks

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Design and Test of Communication Networks for Aids to Navigation based on AIS (AIS 기반의 항로표지 통신망 서비스 설계 및 실험)

  • Park, In-Hwan;Lee, Seo-Jeong;Hwang, Seung-Wook
    • Journal of Navigation and Port Research
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    • v.34 no.5
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    • pp.337-342
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    • 2010
  • As AIS AtoN has worked an essential role for aids to navigation, the World-wide IALA-Net has announced plans to build the system. Systematic beacon network may offer opportunities to make an infrastructure for information service and upgrade AtoN service performance. This paper proposes Aids to Navigation information service network for e-NAV. Network based on AIS is consist of AIS AtoN channels as Real, Synthetic or Virtual AIS AtoN. And inner network is consist of Wireless networks as AIS, WCDMA, WIFI, WIBRO, USN or VSAT. Introducing of various network systems can lead to combine and design aomong land, beacon and service network infrastructures.

Design and Implementation of Multimedia Sensor Networks with Image Sensor (이미지 센서를 이용한 멀티미디어 센서 네트워크의 설계 및 구현)

  • Lee, Joa-Hyoung;Jo, Young-Tae;Jung, In-Bum
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.3
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    • pp.615-622
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    • 2009
  • Advances in wireless communication and hardware technology have made it possible to manufacture high-performance tiny sensor nodes. More recently, the availability of inexpensive CMOS cameras that are able to capture multimedia data from the environment has fostered the development of Wireless Multimedia Sensor Networks (WMSNs). WMSN with the CMOS imaging sensor which is cheaper and consumes lower power than the CCD will not only enhance existing sensor network but also enable several new application such as multimedia surveillance sensor network, multimedia environment monitoring. This paper presents the design of a multimedia sensor network with the image sensor mote developed by us using the CMOS. Given new multimeida sensor network, the new image collecting protocol was tested and analyzed.

Differentiated Lambda Establishment and Wavelength Assignment based on DMS model for QoS guarantees in DWDM Next Generation Internet Backbone Networks (DWDM 차세대 인터넷 백본망에서 DMS 모델 기반의 차등화된 파장할당 및 LSP 설정)

  • Kim, Sung-Un;Lee, Jun-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.9B
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    • pp.760-773
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    • 2003
  • The Internet is evolving from best-effort service toward an integrated or differentiated service framework with quality-of-service (QoS) assurances that are required for new multimedia service applications. Given this increasing demand for high bandwidth Internet with QoS assurances in the coming years, an IP/MPLS-based control plane combined. with a wavelength-routed dense-wavelength division multiplexing (DWDM) optical network is seen as a very promising approach for the realization of future re-configurable transport networks. This paper proposes a differentiated lambda establishment process for QoS guarantees based on the differentiated MPLS service (DMS) model. According to the QoS characteristics of wavelength in optical links and the type of used Optical Cross-Connect (OXC) nodes in DWDM next generation optical Internet backbone network, a differentiated wavelength assignment strategy that considers QoS recovery capability is also suggested.

Improving Reliability and Security in IEEE 802.15.4 Wireless Sensor Networks (IEEE 802.15.4 센서 네트워크에서의 신뢰성 및 보안성 향상 기법)

  • Shon, Tae-Shik;Park, Yong-Suk
    • The KIPS Transactions:PartC
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    • v.16C no.3
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    • pp.407-416
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    • 2009
  • Recently, various application services in wireless sensor networks are more considered than before, and thus reliable and secure communication of sensor network is turning out as one of essential issues. This paper studies such communication in IEEE 802.15.4 based sensor network. We present IMHRS (IEEE 802.15.4 MAC-based Hybrid hop-by-hop Reliability Scheme) employing EHHR (Enhanced Hop-by-Hop Reliability), which uses Hop-cache and Hop-ack and ALC (Adaptive Link Control), which considers link status and packet type. Also, by selecting security suite depending on network and application type, energy efficiency is considered based on HAS (Hybrid Adaptive Security) Framework. The presented schemes are evaluated by simulations and experiments. Besides, the prototype system is developed and tested to show the potential efficiency.

Design of the Upstream Cable Modem for Symmetric Multimedia Services over HFC Networks (HFC망 기반 대칭형 멀티미디어 서비스를 위한 상향 채널 케이블 모뎀 설계)

  • Cho, Byung Hak
    • Journal of Broadcast Engineering
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    • v.10 no.3
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    • pp.401-412
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    • 2005
  • We propose and design the algorithms of symbol timing recovery, carrier recovery, and equalization for the receiver of S-DMT cable modem, which supports more channels and better symmetric mutimedia services over HFC network. We evaluate the performance of the concatenated entire receiving system of 16QAM, 64QAM in the mixed noise channel of AWGN, ISI and impulse. The result of evaluation shows those algorithms work correctly and designed S-DMT receiver has good performance. We also verify the designed system has excellent immunity against impulse noise channel of practical Cable TV networks by the result of simulation with the parameters of impulse internal $\varepsilon$ and noise power $\gamma^{k}$.

Reliable and Effective Overlay Network based Dissemination System for Flash Dissemination (플래쉬 디세미네이션을 위한 안정적이고 효과적인 오버레이 네트워크 기반 전송 시스템)

  • Kim, Kyung Baek
    • Smart Media Journal
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    • v.2 no.1
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    • pp.8-16
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    • 2013
  • The significant enhancement of the edge portion of computer networks including user-side machines and last mile network links encourages the research of the overlay network based data dissemination systems. Varieties of overlay network based data dissemination systems has distinct purposes, and each of them has a proper structure of an overlay network and a efficient communication protocol. In this paper, overlay network based data dissemination systems for Flash Dissemination, whose target is the distribution of relatively small size data to very large number of recipients within very short time, are explored. Mainly two systems, RECREW and FaReCAST, are introduced and analyzed in the aspects of design considerations for overlay networks and communication protocols. According to evaluations for flash dissemination scenarios, it is observed that the proposed overlay network based flash dissemination systems outperforms the previous overlay network based multicasting systems, in terms of the reliability and the dissemination delay. Moreover, the theoretical analysis of the reliability of data dissemination is provided by analysing FaReCAST.

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A Study on the Detection Technique of DDoS Attacks on the Software-Defined Networks (소프트웨어-정의 네트워크에서 분산형 서비스 거부(DDoS) 공격에 대한 탐지 기술 연구)

  • Kim, SoonGohn
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.1
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    • pp.81-87
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    • 2020
  • Recently, the network configuration is being rapidly changed to enable easy and free network service configuration based on SDN/NFV. Despite the many advantages and applications of SDN, many security issues such as Distributed Denial of Service (DDoS) attacks are being constantly raised as research issues. In particular, the effectiveness of DDoS attacks is much faster, SDN is causing more and more fatal damage. In this paper, we propose an entropy-based technique to detect and mitigate DDoS attacks in SDN, and prove it through experiments. The proposed scheme is designed to mitigate these attacks by detecting DDoS attacks on single and multiple victim systems and using time - specific techniques. We confirmed the effectiveness of the proposed scheme to reduce packet loss rate by 20(19.86)% while generating 3.21% network congestion.

A Design for Medical Information System of Emergency Situation Prediction using Body Signal (생체신호를 이용한 응급상황 예측 의료정보 시스템의 설계)

  • Park, Sun;Kim, Chul Won
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.3 no.4
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    • pp.28-34
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    • 2010
  • In this paper, we proposes a emergency medical information system for predicting emergency situation by using the body's vital signs. Main research of existing emergency system has focused on body sensor networks. The problem of these studies have a delay of the emergency first aid since occurring of an emergency situation send a message of emergency situation to user. In the serious situation, patients of these problem can lead to death. To solve this problem, it need to the prediction of emergency situation for doing quickly the First Aid with identify signs of a pre-emergency situations until an emergency occurs. In this paper, the sensor network technology, the security technology, the internet information retrieval techniques, data mining technology, and medical information are studied for the convergence of medical information systems of the prediction of emergency situations.

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Analysis of the TCP performance over IEEE1394 based Home Networkings (IEEE1394 기반의 홈 네트워킹에서의 TCP 성능 분석)

  • 장종욱
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.4
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    • pp.706-715
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    • 2001
  • TCP typically offers reasonable end-to-end performance to users regardless of the bandwidth and error characteristics of particular network technology, The robustness of TCP has contributed to its success in the internet environment. The role of communications is already well established in the office environment. With the advent of cheap, affordable broadband communications and the increasing complexity of consumer goods, it seems natural to extend the network into homes. In-home networking means a high-speed communication among the digital appliances within a home. Introduction of application over high-speed home network using TCP/IP protocol is increasing. The integrated environment of internet and home network is demanding as well. We have validated TCP model over high speed home network environment, investigated the throughput behavior of TCP over IEEE 1399 home networks, and evaluated a potential solution for high performance of TCP over IEEE 139t home networks. The simulation model has produced several interesting results in the performance of TCP over IEEE 1394 home network.

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A Performance Comparison of Routing Protocols for Mobile Ad hoc Networks using the NS-3 (NS-3를 사용한 이동 애드혹 네트워크용 라우팅 프로토콜 성능 비교)

  • Jang, Jaeshin;Ngo, Van-Vuong;Wie, Sunghong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.2
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    • pp.308-316
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    • 2015
  • In this paper, we carried out performance comparison of four routing protocols that had been proposed for mobile ad hoc networks using the NS-3 network simulator. Those four routing protocols consist of two proactive routing protocols, DSDV(destination-sequenced distance vector) and OLSR(optimized link state routing), and two reactive routing protocols, AODV(ad-hoc on-demand distance vector) and DSR(dynamic source routing). Two performance metrics, system throughput and packet delivery ratio, are adopted and performance evaluation was carried out in a square communication area where each communicating mobile node moves independently. Numerical results show that the AODV routing protocol provides the best performance among those four routing protocols.