• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.180-185
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• 2006

자기 유사성(self-similarity)은 다양한 네트워크 환경에서 공통적으로 발생하는 현상인 것으로 정체 제어에서 자기 유사성 트래픽의 장거리 상관 구조를 활용할 가능성과 MTS(Multiple Time Scale) 정체 제어의 프레임워크를 발전시켜, 이 프레임워크가 전송 율 기반 피드백 제어의 성능을 향상시키는 데 시뮬레이션을 통해 트래픽 조건으로 다음과 같이 연구한다. 자기유사성 트래픽 조건에서 3가지 단계로 구성한다. 먼저 TCP의 모듈 형 확장에서 Tahoe, Reno, Vegas등 다양한 버전의 TCP에 적용되는 간단한 인터페이스를 통한 함수 호출을 정의하고, 이것이 성능을 크게 향상시는 것을 입증한다. 두 번째로, 광대역 WAN에서 지연-대역폭의 곱이 높을 경우 더욱 심각해지는 사후 제어의 불확실성 차이를 해소함으로써 MTS TCP가 기반 피드백 제어에 사전성을 부여한다는 것을 입증한다. 세번째는 트래픽 제어의 3가지 차원인, 즉 추적 능력, 연결 지속 기간, 공정성이 성능에 미치는 영향 등을 비교 분석하여 입증한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.65-75
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• 2005

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. We have advanced the framework of the multiple time scale congestion control and showed its effectiveness at enhancing performance for the rate-based feedback control. Our contribution is threefold. First, we define a modular extension of the TCP-a function called with a simple interface-that applies to various flavours of the TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.143-146
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• 2007

컴퓨터 네트워크에서 전송제어 프로토콜 상에서 다중시간 간격으로 혼잡제어의 지연을 피드백 루프의 시간간격을 조정하여 명시적 예측을 실행해 제어의 단점을 개선하는데 연구한다. 먼저 TCP의 모둘 형 확장에서 Tahoe, Reno, Vegas등 다양한 버전의 TCP에 적용되는 간단한 인터페이스를 통한 함수 호출을 정의하고, 이것이 성능을 크게 향상시는 것을 입증한다. 두 번째로, 광대역 WAN에서 지연-대역폭의 곱이 높을 경우 더욱 심각해지는 사후 제어의 불확실성 차이를 해소함으로써 MTS TCP가 기반 피드백 제어에 사전성을 부여한다는 것을 입증한다. 세번째는 트래픽 제어의 3가지 차원인, 즉 추적 능력, 연결 지속 기간, 공정성이 성능에 미치는 영향 등을 비교 분석하여 입증한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.75-80
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• 2008

Measurement of network traffic have shown that the self-similarity is a ubiquitous phenomenon spanning across diverse network environments. In previous work, we have explored the feasibility of exploiting the long-range correlation structure in a self-similar traffic for the congestion control. We have advanced the framework of the multiple time scale congestion control and showed its effectiveness at enhancing performance for the rate-based feedback control. Our contribution is threefold. First, we define a modular extension of the TCP-a function called with a simple interface-that applies to various flavours of the TCP-e.g., Tahoe, Reno, Vegas and show that it significantly improves performance. Second, we show that a multiple time scale TCP endows the underlying feedback control with proactivity by bridging the uncertainty gap associated with reactive controls which is exacerbated by the high delay-bandwidth product in broadband wide area networks. Third, we investigate the influence of the three traffic control dimensions-tracking ability, connection duration, and fairness-on performance.

• The Journal of the Korea institute of electronic communication sciences
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• v.2 no.1
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• pp.10-18
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• 2007

In this paper, we extend the multiple time scale control framework to window-based congestion control, in particular, TCP. This is performed by interfacing TCP with a large time scale control module which adjusts the aggressiveness of bandwidth consumption behavior exhibited by TCP as a function of "large time scale" network state. i.e., conformation that exceeds the horizon of the feedback loop as determined by RTT. Performance evaluation of multiple time scale TCP is facilitated by a simulation bench-mark environment which is based on physical modeling of self-similar traffic. If source traffic is not extended exceeding, when RTT is 450ms, in self similar burst environment, performance gain of TCP-SSC is up to 45% for ${\alpha}$=1.05. However, its is acquired only 20% performance gain for ${\alpha}$=1.95 relatively. Therefore we showed that by TCP-MTS at large time scale into a rate-based feedback congestion control, we are able to improve two times performance significantly.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.2
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• pp.295-303
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• 2004

In this Paper, we discuss an active TCP link of unsynchronized transmission mode network in two-way traffic and the Improvement of its traffic patron thorough the network pathway of protocol is shown. This is because the traffic pattern is performed on the basis of existing windows which are distributing information in several periods of time in the way of interfacing LTS control module, which is controlling by an information of exceeding the time limit of feedback loop determined by RTP, with TCP. The simulation to utilize this efficiently is performed with the circumstance of bench mark based on physical modeling of the self-similarity traffic in the performance of TCP. In this paper, we use a methodology to understand and evaluate the effect of change of transmitting protocol in sticks under the condition of the self-similar traffic in two-way network and it is shown that an improvement of congestion control by self-similarity under a heavy condition.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.6B
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• pp.575-583
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• 2004

In this paper, we extend the multiple time scale control framework to the window-based congestion control, in particular, such as the TCP. This is performed by interfacing the TCP with a large time scale control module which adjusts the aggressiveness of the bandwidth consumption behavior exhibited by the TCP as a function of large time scale Self-Similar network state. i.e., conformation that exceeds the horizon of the feedback loop as determined by the RTT. How to effectively utilize such an information-due to its probabilistic nature, dispersion over the multiple time scales, and affection on the top of the existing window-based congestion controls-is a non-trivial problem. The evaluation performance of the multiple time scale TCP is facilitated by a simulation of the bench-mark environment which is based on the physical modeling of a self-similar traffic. We explicate our methodology for discerning and evaluating the impact of changes in transport protocols in the protocol stack under the self-similar traffic conditions. We discuss issues arising in the comparative performance evaluation under heavy-tailed workloads.

• Proceedings of the KAIS Fall Conference
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• 2007.05a
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• pp.154-157
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• 2007

본 논문에서는 컴퓨터로 정밀 계측기기들을 자동 제어하고 데이터를 측정하기 위하여 기존의 상용 프로그램을 사용하지 않고 Excel VBA(Visual Basic for Applications)를 이용하는 방법에 대하여 연구 하였다. 이는 반복측정 및 통계적 수치계산 등에서 많은 장점을 지니고 있어 수많은 국가교정기관 및 일반 산업체에서 유용하게 사용될 수 있으리라 사료된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.1
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• pp.70-74
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• 2008

We are using COS to purpose blocking the excess current and to protect the transformer. But the fuse of COS is melt due to the overload if the excess current flows and it destroy an air severing relations to clear as strong arc happens. Such phenomenon induces an impact ambient noise and it gives the circumstance area resident or pedestrian the fear. Thus, We are the actual circumstances which an ambient noise countermeasure establishment have desired urgently. In this study, we grasp the characteristic of an impact ambient noise which a COS fuse happens the melting and study the method to reduce an impact ambient noise.