• Title/Summary/Keyword: Network Time Protocol

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Design of Intrusion Responsible System For Enterprise Security Management (통합보안 관리를 위한 침입대응 시스템 설계)

  • Lee, Chang-Woo;Sohn, Woo-Yong;Song, Jung-Gil
    • Convergence Security Journal
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    • v.5 no.2
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    • pp.51-56
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    • 2005
  • Service operating management to keep stable and effective environment according as user increase and network environment of the Internet become complex gradually and requirements of offered service and user become various is felt constraint gradually. To solve this problem, invasion confrontation system through proposed this log analysis can be consisted as search of log file that is XML's advantage storing log file by XML form is easy and fast, and can have advantage log files of system analyze unification and manages according to structure anger of data. Also, created log file by Internet Protocol Address sort by do log and by Port number sort do log, invasion type sort log file and comparative analysis created in other invasion feeler system because change sort to various form such as do log by do logarithm, feeler time possible.

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The Binding Update Method using Delegation of Rights in MIPv6 (MIPv6에서 권한위임을 이용한 위치수정 방안)

  • 이달원;이명훈;황일선;정회경;조인준
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.6
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    • pp.1194-1203
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    • 2004
  • The RR protocole, proposed in IETF mip6 WG and standardized by RFC 3775 at lune 2004, send a message 'Binding Update' that express MN's location information to CN safety and update location information. Standard RR protocole has some problems with initiating the protocol by the MN; it causes to increases in communication load in the home network, to increases communication delay between MN and CN. Also, is connoting vulnerability to against attacker who are on the path between CN and HA in security aspect. This paper proposes doing to delegate MN's location information update rights by HA new location information update method. That is, When update MN's location information to HA, Using MN's private key signed location information certificate use and this certificate using method that HA uses MN's location information at update to CN be. It decreases the route optimization overhead by reducing the number of messages as well as the using location information update time. Also, remove security weakness about against attacker who are on the path between CN and HA.

Backscatter Communication for Wireless-Powered Communication Networks (무선전력 통신네트워크를 위한 Backscatter 통신)

  • Choi, Shin Hyuk;Kim, Dong In
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.10
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    • pp.1900-1911
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    • 2015
  • In this paper, we introduce backscatter communication for power-limited sensors to enable long-range transmission in wireless sensor networks, and envision a way to avoid doubly near-far problem in wireless-powered communication network (WPCN) with this technology. In backscatter based WPCN, users harvest energy from both the signal broadcasted by the hybrid access point and the carrier signal transmitted by the carrier emitter in the downlink, and then transmit their own information in a passive way via the reflection of the carrier signal using frequency-shift keying modulation in the uplink. We characterize the energy-free condition and the signal-to-noise ratio (SNR) outage zone in backscatter based WPCN. Further, we propose backscatter based harvest-then-transmit protocol to maximize the sum-throughput of the backscatter based WPCN by optimally allocating time for energy harvesting and information transmission. Numerical results demonstrate that the backscatter based WPCN increases significantly the transmission range and diminishes greatly the SNR outage zone.

A study of real-time media streaming delivery over P2P networks (P2P 환경에서 실시간 미디어스트리밍의 전송에 관한 연구)

  • Liu Xu-dong;Jo In-June
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2006.05a
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    • pp.538-541
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    • 2006
  • Recently researches of P2P media streaming have been actively published, but the research what kind of P2P overlay networks are better to delivering media data has not been attended. This paper designs a P2P streaming media system model. In this system, we constructs a Half-Structure P2P overlay protocol based on node's capability as the infrastructure of streaming application, which utilizes the heterogeneity of the nodes to maintain topology, presents a active contents diffusing algorithm and Two-stage search algorithm, make it possible for nodes in P2P system to collect information according their capacity and reduces the number of forwarding packet compared with flooding. Also, we give an optimal scheme to scheduling media data.

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A resource reservation method adjusting the delay budgets of a traffic flow allocated to the RSVP-capable routers (RSVP-라우터에 할당되는 트래픽 흐름의 지연규격을 조정하는 자원예약 방식)

  • Kim, Tae-Joon
    • Journal of Korea Multimedia Society
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    • v.11 no.7
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    • pp.966-976
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    • 2008
  • Providing Quality-of-Service(QoS) guarantee requires the reservation of resource needed to accommodate the traffic flow of service for which resource reservation protocol(RSVP) was introduced. However, if any RSVP-capable router on the path fails to accommodate the traffic flow due to lack of resource, the flow is not allowed no matter how much surplus resources other routers on the path have. In order to solve this problem, this paper proposes a resource reservation method that can adjust adaptively the delay budget of traffic flow allocated to each RSVP-capable router in which the router uses the recently developed general-time fair queuing scheduler. The results of the simulation applying the proposed method to an evaluation network show that it may yield the gain of up to 90% compared to that in the original one in terms of the number of admitted flows.

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Seamless handover protocol to reduce handover latency (핸드오버 지연 시간을 줄일 수 있는 심리스 핸드오버 프로토콜 제안 및 성능 분석)

  • Jang, Jong-Min;Lee, Yu-Tae;Lee, Soong-Hee;Kim, Dong-Il;Choi, Sam-Gil
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.2
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    • pp.277-284
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    • 2009
  • With significant development in wireless communication technologies, the needs to handover from one network to another have grown dramatically. Recently IETF developed MIPv6 and FMIPv6 which are used to handover between different access networks. These handover mechanisms have some known weaknesses. MIPv6 can not serve time-critical application because it causes long handover latency and packet loss. By these reasons, MIPv6 does not guarantee session continuity. FMIPv6 uses handover preparation phase to reduce DAD latency. However FMIPv66 still suffers from long handover latency, because it must perform binding update at the end of handover procedure. In this paper we propose new handover mechanism FMIPv6-PBU which eliminates binding update latency. The proposed mechanism has compatability with lagacy FMIPv6. In this paper propose FMIPv6-PBU handover procedure and explain its procedures and evaluate it with MIPv6 and FMIPv6.

Wireless operational modal analysis of a multi-span prestressed concrete bridge for structural identification

  • Whelan, Matthew J.;Gangone, Michael V.;Janoyan, Kerop D.;Hoult, Neil A.;Middleton, Campbell R.;Soga, Kenichi
    • Smart Structures and Systems
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    • v.6 no.5_6
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    • pp.579-593
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    • 2010
  • Low-power radio frequency (RF) chip transceiver technology and the associated structural health monitoring platforms have matured recently to enable high-rate, lossless transmission of measurement data across large-scale sensor networks. The intrinsic value of these advanced capabilities is the allowance for high-quality, rapid operational modal analysis of in-service structures using distributed accelerometers to experimentally characterize the dynamic response. From the analysis afforded through these dynamic data sets, structural identification techniques can then be utilized to develop a well calibrated finite element (FE) model of the structure for baseline development, extended analytical structural evaluation, and load response assessment. This paper presents a case study in which operational modal analysis is performed on a three-span prestressed reinforced concrete bridge using a wireless sensor network. The low-power wireless platform deployed supported a high-rate, lossless transmission protocol enabling real-time remote acquisition of the vibration response as recorded by twenty-nine accelerometers at a 256 Sps sampling rate. Several instrumentation layouts were utilized to assess the global multi-span response using a stationary sensor array as well as the spatially refined response of a single span using roving sensors and reference-based techniques. Subsequent structural identification using FE modeling and iterative updating through comparison with the experimental analysis is then documented to demonstrate the inherent value in dynamic response measurement across structural systems using high-rate wireless sensor networks.

Cross-layer Simulation and Analysis for Video Transmission Quality in MANET (MANET에서 비디오 전송 품질을 위한 Cross-layer 시뮬레이션과 분석)

  • Yoon, Hyoup-Sang
    • Journal of the Korea Society for Simulation
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    • v.24 no.3
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    • pp.61-68
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    • 2015
  • Mobile ad hoc networks (MANETs) are self-organized dynamic networks populated by mobile nodes. This paper presents the improved cross-layer approach to complement the recent works for video transmission services on MANET. We use a statistical design of experiment and analysis in order to investigate interactions between major factors of each layer effectively with minimizing ns-3 simulation run time. The proposed cross-layer approach considers MANET protocol layers (i.e., physical, network and transmission layers) and an application layer (i.e., a video encoder) as factors simultaneously. In addition, the approach defines an objective video quality metric as a response variable. The result of this paper can be applicable as a preliminary research to design an optimized video transmission application which has ability to adjust controllable factors to dynamic uncontrollable factors.

Augmented Reality Framework to Visualize Information about Construction Resources Based on Object Detection (웨어러블 AR 기기를 이용한 객체인식 기반의 건설 현장 정보 시각화 구현)

  • Pham, Hung;Nguyen, Linh;Lee, Yong-Ju;Park, Man-Woo;Song, Eun-Seok
    • Journal of KIBIM
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    • v.11 no.3
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    • pp.45-54
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    • 2021
  • The augmented reality (AR) has recently became an attractive technology in construction industry, which can play a critical role in realizing smart construction concepts. The AR has a great potential to help construction workers access digitalized information about design and construction more flexibly and efficiently. Though several AR applications have been introduced for on-site made to enhance on-site and off-site tasks, few are utilized in actual construction fields. This paper proposes a new AR framework that provides on-site managers with an opportunity to easily access the information about construction resources such as workers and equipment. The framework records videos with the camera installed on a wearable AR device and streams the video in a server equipped with high-performance processors, which runs an object detection algorithm on the streamed video in real time. The detection results are sent back to the AR device so that menu buttons are visualized on the detected objects in the user's view. A user is allowed to access the information about a worker or equipment appeared in one's view, by touching the menu button visualized on the resource. This paper details implementing parts of the framework, which requires the data transmission between the AR device and the server. It also discusses thoroughly about accompanied issues and the feasibility of the proposed framework.

Multi-channel Video Analysis Based on Deep Learning for Video Surveillance (보안 감시를 위한 심층학습 기반 다채널 영상 분석)

  • Park, Jang-Sik;Wiranegara, Marshall;Son, Geum-Young
    • The Journal of the Korea institute of electronic communication sciences
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    • v.13 no.6
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    • pp.1263-1268
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    • 2018
  • In this paper, a video analysis is proposed to implement video surveillance system with deep learning object detection and probabilistic data association filter for tracking multiple objects, and suggests its implementation using GPU. The proposed video analysis technique involves object detection and object tracking sequentially. The deep learning network architecture uses ResNet for object detection and applies probabilistic data association filter for multiple objects tracking. The proposed video analysis technique can be used to detect intruders illegally trespassing any restricted area or to count the number of people entering a specified area. As a results of simulations and experiments, 48 channels of videos can be analyzed at a speed of about 27 fps and real-time video analysis is possible through RTSP protocol.