• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.9
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• pp.485-490
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• 2006

According to the computerization of railway signaling systems, the interface link between the signaling systems has been replaced by the digital communication channel. At the same time, the importance of the communication link is more pronounced than before. In this paper, new Network-based protocol between railway signaling and SCADA (Supervisory Control and Data Acquisition system) has designed and the overview of designed protocol is briefly represented. And also this paper addresses analysis of newly designed train control systems. Fame error rates of the data transmissions are calculated and compared for the two cases that the CTC (Centralized Traffic Control)/SCADA has an extra data transmission error control (CRC16) besides the inherent error control of the Ethernet and that the CTC/SCADA has no extra data transmission error control. With simulation results it has been verified that the additional error control code contributes to lowering the frame error rate. It will be expected to increase the safety, reliability and efficiency of maintenance of the signaling systems by using the designed protocol for railway signaling system.

• Journal of the Korean Society for Railway
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• v.7 no.4
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• pp.296-301
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• 2004

This paper addresses an analysis for a railway data transmission protocol-Ethernet based data transmission between the CTC(Centralized Traffic Control System) and the SCADA(Supervisory Control and Data Acquisition) system. Fame error rates of the data transmissions are calculated and compared for the two cases that the CTC/SCADA has an extra data transmission error control(CRCI6) besides the inherent error control of the Ethernet(CRC32), and that the CTC/SCADA has no extra data transmission error control. With simulation results it has been verified that the extra data transmission error control(CRC16) contributes to lowering the frame error rate.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.9
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• pp.1283-1294
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• 1993

The conventional transport protocols, developed on top of the low-bandwidth high-error network services, exhibit poor performances when operating in the new high-bandwidth low-error networks. A new transport protocol HSTP(High Speed Transport Protocol) was proposed to take advantage of the new network environment. This paper gives a performance evaluation by simulation technique of the proposed HSTP and conventional TP4(Transport Protocol class 4) in their data trans-fer characteristics. The performance variation by HSTP and TP4 are investigated when their various error control techniques are employed, three different techniques for HSTP, and two for TP4. The performance enhancement in HSTP is also evaluated when the rate control technique is used as part of the flow control mechanisms.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.234-236
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• 2004

Transmission control protocol(TCP) is protocol used in internet. TCP is seldom transmission error and is protocol based on wire environment. TCP uses 3 way handshake ways, data transmission control through windows size, data transmission control through reception confirmation, sliding window for packet delivery. In this study, designed TCP packet ion module for analyze the TCP segments & correct information about TCP. TCP capture in internet using designed TCP module and analysed TCP segments composition. Through this, could analyze the correct information of protocol in network.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.10A
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• pp.1532-1538
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• 1999

In general, because error rate of wireless link is higher than that of wired link, DLC layer protocol for wired network with low error rate is not proper for wireless environments. In addition, the conventional DLC layer protocol for wireless network is optimized for the low-speed data service, so it is difficult to use conventional DLC protocol in the current mobile communication environments handing high-speed and multimedia services. Therefore, a DLC layer protocol that is suitable to current wireless communication environments is required. In this paper, we propose a novel error control scheme that supports a variety of traffic attribute and is applicable to high-speed and multimedia data service in WATM. The proposed scheme provides enhanced throughput performance for real-time traffic by using modified ASR ARQ without ACK and reduces loss rate by using FEC in the case of high error condition. Also, for non real-time traffic, the use of ASR ARQ without ACK enhances throughput performance and delay time is decreased by using FEC in the case of high error rate channel. As a result of simulation, the proposed scheme has better performance than conventional ASR ARQ protocol in view of delay and throughput.

• Journal of information and communication convergence engineering
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• v.6 no.2
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• pp.134-139
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• 2008

In this paper, we propose an analysis model for the performance of channel error probability in Stream Control Transmission Protocol (SCTP) using Markov model. In this model it is assumed that the compressor and decompressor work in Unidirectional Mode. And the average throughput of SCTP protocol is obtained by finding the throughputs of when the initial channel state is good or bad.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.642-649
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• 2018

The Modbus protocol is the most widely used protocol for connecting multiple slave control units (SCUs) in the master control unit. However, the Modbus protocol does not identify which SCU response message corresponds to the service request message. Therefore, when using the Modbus protocol, one service request message can be transmitted after processing the previous message. In this paper, we propose a Modbus application protocol with an index code and a service code to solve the problem. As a result of experimentation, it is possible to transmit the next service request message without processing the previous service request message. And when a communications error occurs, it is possible to identify what type of error occurred using an error detection algorithm. Also, with simultaneous multiple service requests, the proposed protocol can improve processing time by about 66.2%, compared to the original Modbus protocol.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.605-609
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• 2002

Reliable multicast data transmission in a 1:N environment needs more sophisticated error control mechanism than that of in 1:1 environment due to ACK implosion and duplicated retransmission. Although there have been many related research on error control in reliable multicast, real implemented protocols are rare. As one of the reliable multicast transport protocols, ECTP is selected as an international standard reliable multicast protocol by ITU-T and ISO and implemented on RedHat 7.2 machine by us. In this paper, we evaluate the performance of the error control mechanism in the respect of throughput and generated control packet numbers with a real implementation code. From the results, it is concluded that the suitable values of error control parameters can be obtained from the local group size and network environments.

• Journal of information and communication convergence engineering
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• v.5 no.3
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• pp.194-199
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• 2007

In this paper, a slotted CDMA_ALOHA protocol with hybrid ARQ is proposed for the wireless CDMA communication networks. The proposed protocol combines the characteristics of the slotted ALOHA, CDMA, and the hybrid ARQ, in order to increase the throughput by reducing the number of retransmissions when the channel experiences heavy traffic. The main feature of the proposed protocol is the utilization of the forward error correction capability to correct errors that appear after the CDMA dispreading of the packets. The base station does not need to ask so often for retransmission of erroneous packets. It will request for retransmission only when the FEC capability is exceeded. The performance of the proposed protocol is analyzed by considering the packet collision probability as well as the bit error probability. The numerical results show that the system throughput is closely related to the bit error rate of the wireless link and the FEC coding rate.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.9
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• pp.349-357
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• 2003

Because of capacity of the electric power equipment grew larger and the electric power system was complicated, it was required a protocol to process data without the errors in order to supply the high quality and stable electric power. However, HDLC and TCP/IP communication protocol using between Seoul EMS and Kwangju RCC (or between RCC and SCC) is decreasing reliability by the delay of speed and the occurrence of errors. In this paper, we applied ICCP(Inter-Control Center Communication Protocol) communication protocol in order to improve them and implemented an electric power communication system for remote control of the electric power equipment. Also, we modified program for error correction and implemented the system using the most suitable BLT. The errors were more decreased in case of ICCP protocol than HDLC protocol and TCP/IP protocol applied to the electric power communication system.