• The Transactions of the Korea Information Processing Society
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• v.6 no.11S
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• pp.3390-3398
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• 1999

To achieve high-speed communication and to improve QoS characteristics, ATM is now being used as underlying transfer mechanism of Internet protocols, or TCP/IP. When TCP uses the ABR service in ATM networks, the ABR service control is important to improve the performance of TCP/IP traffic as long as there is no interaction between ABR rate control and TCP flow control. In such environment, the interoperability of EFCI and ER switches becomes unavoidable in order to more effectively control ABR traffic in ATM network. In this paper, we use the model of mixed EFCI-ER environment and discuss the performance issues, e.g., the fairness of bandwidth allocation, drop rate, throughput by using various ER switch algorithms. Among various ERSwitch algorithms, we present one algorithm that have a less network topology and allocate the fair share of VC bandwidth by simulation results.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.10
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• pp.789-797
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• 2003

An implementation scheme and some improvements are proposed to adopt public-licensed operating system, Linux and de-facto world-wide network standard, TCP/IP into the field of behavior-based autonomous mobile robots. To demonstrate the needs of scheme and the improvement, an analysis is performed on a server/client communication problem with real time Linux previously proposed, and another analysis is also performed on interactions among TCP/IP communications and the performance of Linux system using them. Implementation of behavior-based control architecture on real time Linux is proposed firstly. Revised task-scheduling schemes are proposed that can enhance the performance of server/client communication among local tasks on a Linux platform. A new method of TCP/IP packet flow handling is proposed that prioritizes TCP/IP software interrupts with aperiodic server mechanism as well. To evaluate the implementation scheme and the proposed improvements, performance enhancements are shown through some simulations.

• Journal of IKEEE
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• v.2 no.1 s.2
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• pp.42-52
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• 1998

This paper proposes an extended TCP/IP protocol, LAN/TCP, that can be used for the distributed soft real-time systems connected through the Ethernet-based local area network. Since LAN/TCP shows soft real-time performance with keeping compatibility and interoperability with the standard TCP/IP, the existing application software can be used without any modification. LAN/TCP also provides the periodic transmission mode(PTM) with which the periodical data collection and updating the control signals can be efficiently implemented with relatively small traffic overhead. This paper includes the computer simulation and experimental results of the proposed protocol.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.06a
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• pp.83-86
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• 2007

The necessity of the high speed exclusive use server that connect digital measure instrument flag to internet and CPU use rate of measure flag uses other imbedded operating system with many general servers to verification & proofreading system in remotion. This research is objective that embody high speed network module for Site-Based remote verification & proofreading system and through internet digital measure instrument flag to remote verification & proofreading, TCP/IP Offload Engine processing and improved that is Imbedded TCP/IP stack for high speed networking.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.6
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• pp.1077-1082
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• 2007

The necessity of the high speed exclusive use server that connect digital measure instrument flag to internet and CPU use rate of measure flag uses other imbedded operating system with many general servers to verification & proofreading system in remotion. This research is objective that embody high speed network module for Site-Based remote verification & proofreading system and through internet digital measure instrument flag to remote verification & proofreading, TCP/IP Offload Engine processing and improved that is Imbedded TCP/IP stack for high speed networking.

• Journal of KIISE:Computer Systems and Theory
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• v.34 no.9
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• pp.459-466
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• 2007

TCP/IP processing imposes a heavy load on the host CPU when it is processed by the host CPU on a very high-speed network. Recently the TCP/IP Offload Engine (TOE), which processes TCP/IP on a network adapter instead of the host CPU, has become an attractive solution to reduce the load in the host CPU. There have been two approaches to implement TOE. One is the software TOE in which TCP/IP is processed by an embedded processor and the other is the hardware TOE in which TCP/IP is processed by a dedicated ASIC. The software TOE has poor performance and the hardware TOE is neither flexible nor expandable enough to add new features. In this paper we designed and implemented a hybrid TOE architecture, in which TCP/IP is processed by cooperation of hardware and software, based on an FPGA that has two embedded processor cores. The hybrid TOE can have high performance by processing time-critical operations such as making and processing data packets in hardware. The software based on the embedded Linux performs operations that are not time-critical such as connection establishment, flow control and congestions, thus the hybrid TOE can have enough flexibility and expandability. To improve the performance of the hybrid TOE, we developed a hardware-based transmission/reception accelerator that processes important operations such as creating data packets. In the experiments the hybrid TOE shows the minimum latency of about $19{\mu}s$. The CPU utilization of the hybrid TOE is below 6 % and the maximum bandwidth of the hybrid TOE is about 675 Mbps.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.3
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• pp.231-242
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• 2004

Remote control and monitoring of information appliances require RTOS and TCP/IP network module to communicate each other. Traditional TCP/IP protocol stacks, however, require relatively large resources to be useful in small 8 or 16-bit systems both in terms of code size and memory usage. It motivates design and implementation of micro TCP/IP that is lightweight for embedded systems. Micro embedded web server is also required to control and monitor information appliances through the Web. In this paper, we design and implement micro TCP/IP and Web server for information appliances. For this goal, we investigate requirements for the interoperability of embedded systems with the Internet and the Web-based control of embedded systems. Next, we compare our micro TCP/IP protocol stack with that of RTIP and QPlus in terms of object code size and performance. The size of micro TCP/IP protocol stack can be reduced by 3/2 and 1/4, respectively, comparing with that of RTIP and QPlus. We also show that the performance of our micro TCP/IP is similar to that of RTIP and QPlus since it handles 2.9Mbps when delayed ACK is not adapted.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.37 no.3
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• pp.86-92
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• 2000

In this paper, we develop protocol analyzer that can analyze and monitor LAN(Local Area Network)-based TCP/IP protocol using the OOP(object-oriented programming) in Windows98/NT environment. TCP/IP(Transmission Control Protocol/Internet Protocol) protocol analyzer is consist of interface hardware, protocol analysis software and GUI(Graphic User Interface). It is designed for the real-time analysis using the real-time object. In results of Performance test, TCP/IP Protocol analyzer is showed that it can analyze and monitor without frame error in LAN-based. Also, developed protocol analyser operates better than conventional protocol analyzer in performance. It can be used in maintenance fields of communication and network.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.4
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• pp.99-104
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• 2010

We introduce Internet TCP/IP control system to monitor the traffic volume on the traffic network system. To check the traffic volume on traffic road, we use the traffic detector system shppe of circle or diamond or rectangular. Nevertheless we use traffic detector, we will use internet addressin TCP/IP system. If we use TCP/IP control system, we acquire many good point, we achive high sircurity and low costness traffic monitoring system coming difficulty and high level position. But internet system is very easy and low cost direction. Traffic control system is very more depending on the high techinquesion and very complexity. Therefore we introducing TCP/IP internet addressing control system schemetic point.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.05a
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• pp.270-275
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• 1998

무선망에서는 높은 에러율과 핸드오프로 인해 패킷 손실이 자주 발생한다. 그러나, 기존의 TCP/IP 프로토콜에서는 패킷 손실을 혼잡에 의해서 발생한 것이라 보고, 패킷 송신율을 줄임으로써 혼잡제어를 실시한다. 따라서 기존의 TCP/IP 프로토콜을 무선망에 그대로 적용했을 경우 매우 낮은 성능을 나타낸다. 본 연구에서는 무선망에서의 국부적인 재전송을 통하여 패킷 손실을 보완하고, 사용자가 셀 간을 이동할 때 핸드오프 지연시간을 줄일 수 있는 새로운 핸드오프 방식을 제안한다. 시뮬레이션을 통해서 제안된 방법을 성능을 평가한다.