• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2714-2716
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• 2001

본 논문에서는 일대일 전송에 국한되어 사용되는 전이중 패스트 이더넷 방식을 응용하여 고속 브로드 캐스팅 통신망을 구성하고 실시간 전송을 요구하는 데이터를 효율적으로 전달할 수 있는 알고리듬을 제시한다. 제안된 통신망의 세부구조와 통신망의 데이터 송수신 동작 등을 설명하고, 실시간 데이터 전송을 보장하기 위하여 실시간 메시지 스케줄링 알고리듬을 제시한다. 제시된 알고리듬을 적용하였을 때의 각종 시변수들에 대한 수학적인 분석을 통하여 실시간성 보장에 대한 성능평가를 포함한 통신망 성능 평가를 수행한다. 제안된 통신망 FER(Full-duplex Ethernet networks for Real-time communication)의 실제 구현 및 응용 대상에 대해서 언급한다.

• Proceedings of the Optical Society of Korea Conference
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• 2006.07a
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• pp.211-212
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• 2006

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.2A
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• pp.86-96
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• 2006

In recent year, EPON(Ethernet PON) system is expected to be more attractive solutions for high speed, broadband access networks in next generation access networks due to the conversionce of low-cost ethernet equipment and low-cost fiber infrastructure. Upstream channel control algorithm is essential to hare upstream bandwidth in EPON. In this paper, we suggest HUHG(High Utilization and Hybrid Granting) algorithm for supporting high bandwidth utilization and QoS for different service class. This algorithm improves bandwidth utilization as removing or diminishing idle time of upstream channel using characteristics of fixed EF(Expedited Forwarding) sub-cycle. The proposed algorithm also minimizes the packet delay and delay variation of EF class. We conduct detailed simulation experiments using OPNET to study the performance and validate the effectiveness of the proposed algorithm.

• Journal of Communications and Networks
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• v.8 no.4
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• pp.480-484
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• 2006

This paper briefly reviews ITU-T recommendations associated with multi protocol label switch (MPLS) and Ethernet operation, administration, and maintenance (OAM). The broadband convergence network (BcN) architecture with a centralized network controller is introduced. An aggregation structure employing Ethernet, MPLS, and time division multiplexing (TDM) signal is presented for the BcN. A physical link failure scenario is examined to investigate how the maintenance signal is propagated between different layers.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.1117-1120
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• 2002

In general, standard TCP/IP (transmission control protocol-internet protocol), which is called TCP/IP, is using as the communication basis protocol between any collections of networks that is connected. In this paper, using this TCP/IP implementation of remote system and suitable program for long distance communication is proposed. This system can make system, which basic Ethernet and TCP/IP used system, to mini modeling, so all module that is using here can be used. Therefore, intention of this paper is to reduce expenses, to effective manage for plant and to increase of productivity as linking each plant of several factories to TCP/IP and Ethernet, and then many control plant and manager minimize the needed course.

• Current Optics and Photonics
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• v.4 no.3
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• pp.186-192
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• 2020

This paper describes a real-time monitoring system in Ethernet passive optical networks (EPON) that uses burst-mode fiber Bragg grating (FBG) optical sensors. The FBG interrogation unit in the optical line terminal (OLT) transmits the monitoring wavelength to optical network units (ONUs). The FBG sensor unit in each ONU returns a burst-mode monitoring signal to the OLT. As the system applies time division multiple access (TDMA), a uniform Bragg wavelength can be used to monitor the EPON system. The FBG interrogation unit analyzes the received burst-mode monitoring signals and outputs fault information on the ONU branches in EPON. The simulation results show the effectiveness of the proposed monitoring system based on TDMA. In addition, we compared the proposed TDMA-based monitoring system with a WDMA-based monitoring system.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.989-995
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• 2017

Distributed Control System (DCS) communication networks, which use Fast Ethernet with redundant networks for the transmission of information, have been installed in digitalized nuclear power plants. Normally, failover tests are performed to verify the reliability of redundant networks during design and manufacturing phases; however, systematic integrity tests of DCS networks cannot be fully performed during these phases because all relevant equipment is not installed completely during these two phases. In additions, practical verification tests are insufficient, and there is a need to test the actual failover function of DCS redundant networks in the target environment. The purpose of this study is to verify that the failover functions works correctly in certain abnormal conditions during installation and commissioning phase and identify the influence of network failover on the entire DCS. To quantify the effects of network failover in the DCS, the packets (Protocol Data Units) must be collected and resource usage of the system has to be monitored and analyzed. This study introduces the use of a new methodology for verification of DCS network failover during the installation and commissioning phases. This study is expected to provide insight into verification methodology and the failover effects from DCS redundant networks. It also provides test results of network performance from DCS network failover in digitalized domestic nuclear power plants (NPPs).

• Journal of the Korean Society of Systems Engineering
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• v.13 no.2
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• pp.9-17
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• 2017

Concept development of a real-time Field Programmable Gate Array (FPGA)-based switched Ethernet data communication network for the Man-Machine Interface System (MMIS) is presented in this paper. The proposed design discussed in this research is based on the systems engineering (SE) approach. The design methodology is effectively developed by defining the concept development stage of the life-cycle model consisting of three successive phases, which are developed and discussed: needs analysis; concept exploration; and concept definition. This life-cycle model is used to develop an FPGA-based time-triggered Ethernet (TTE) switched data communication network for the non-safety division of MMIS system to provide real-time data transfer from the safety control systems to the non-safety division of MMIS and between the non-safety systems including control, monitoring, and information display systems. The original IEEE standard 802.3 Ethernet networks were not typically designed or implemented for providing real-time data transmission, however implementing a network that provides both real-time and on-demand data transmission is achievable using the real-time Ethernet technology. To develop the design effectively, context diagrams are implied. Conformance to the stakeholders needs, system requirements, and relevant codes and standards together with utilizing the TTE technology are used to analyze, synthesize, and develop the MMIS non-safety data communication network of the APR1400 nuclear power plant.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.11B
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• pp.1579-1587
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• 2010

In this paper, we design the PCS(Physical Coding Sublayer) transmitting and receiving module for 400/1000 Ethernet and verify the performance of it through logic simulation. In this work, we defined each function module and internal/external control signals and implemented them using HDL programming language. We also designed 64B/66B encoding/decoding, scrambling/descrambling including operation mode, detection of invalid frames, and multi-lane based distribution/arrangement. It was simulated using ModelSim and verified in terms of the operation and timing according to input data. The simulation result shows that all designed modules in 400/100G Ethernet are correctly performed.

• Journal of KIISE:Computer Systems and Theory
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• v.29 no.12
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• pp.648-654
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• 2002

The Virtual Interface Architecture(VIA) is an industry standard for communication over system area networks(SANs). M-VIA is a software implementation of VIA technology on Linux. In this paper, we implemented the M-VIA on an AceNIC Gigabit Ethernet by developing a new AceNIC driver for the M-VIA. We analyzed the M-VIA data segmentation processes. When a Gigabit Ethernet MTU is larger than 1514 bytes, M-VIA data segmentation size leaves much room for improvement. So we experimented with various MTU and M-VIA data segmentation size and compared the performances.