• 한국정밀공학회지
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• 제11권4호
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• pp.126-137
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• 1994

Performance management of computer networks is intended to improve a given network performance in order for more efficient information exchange between subsystems of an integrated large-scale system. Importance of perfomance management is growing as many functions of the large- scale system depend on the quality of communication services provided by the network. The role of performance management is to manipulate the adjustable protocol parameters on line so that the network can adapt itself to a dynamic environment. This can be divided into two subtasks : performance evaluation to find how changes in protocol parameters affect the network performance and decision making to determine the magnitude and direction of parameter adjustment. This paper is the first part of the two papers focusing on conceptual design, development, and evaluation of performance management for token bus networks. This paper specifically deals with the task of performance evaluation which utilizes the principle of perturbation analysis of discrete event dynamic systems. The developed algorithm can estimate the network performance under a perturbed protocol parameter setting from observations of the network operations under a nominal parameter setting.

• 한국정보전자통신기술학회논문지
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• 제9권4호
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• pp.313-322
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• 2016

본 논문에서는 멀티캐스트 패킷 재전송을 담당하는 기능을 기지국에 탑재하여 신뢰성있는 멀티캐스트 전송 프로토콜인 Scalable Multicast Protocol 성능을 개선하고자 한다. 유무선 통합망에서 Scalable Multicast Protocol 동작시, 무선 네트워크에서의 비트 에러나 단말의 이동성으로 패킷 재전송이 많이 발생한다. 이런 재전송 때문에 Scalable Multicast Protocol의 그룹에 제어 메시지 및 재전송 메시지가 증가하게 되며, 이는 또한 Scalable Multicast Protocol 세션 전체 성능을 저하시킨다. 본 논문은 기지국에 무선 환경에 있는 단말의 복구 요구 메시지에 대한 복구 메시지 전송을 담당하는 기능을 추가하여 전체 세션의 성능을 높이고자 한다. ARENA를 이용하여 제안한 방법이 멀티캐스트 세션에의 복구 요구 및 복구 메시지의 수를 줄일 수 있고 멀티캐스트 그룹 세션 전체의 성능을 향상시킬 수 있음을 검증하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.54.3-54
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• 2002

$\textbullet$ Introduction $\textbullet$ Token Passing Protocol : Profibus-FMS $\textbullet$ Performance Model of Profibus Token Passing Protocol $\textbullet$ Calculation of Communication Delay in Performance Model $\textbullet$ Summaries and Conclusions

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권2호
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• pp.764-784
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• 2017

Energy efficiency is an essential requirement in designing a MAC protocol for wireless sensor networks (WSNs) using battery-operated sensor nodes. We proposed a new receiver-initiated MAC protocol, RIX-MAC, based on the X-MAX protocol with asynchronous duty cycles. In this paper, we analyzed the performance of RIX-MAC protocol in terms of throughput, delay, and energy consumption using the model. For modeling the protocol, we used the Markov chain model, derived the transmission and state probabilities, and obtained the equations to solve the performance of throughput, delay, and energy consumption. Our proposed model and analysis are validated by comparing numerical results obtained from the model, with simulation results using NS-2.

• 한국전자거래학회지
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• 제7권2호
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• pp.157-171
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• 2002

We want to find a timestamping method which improves efficient performance and have high-level security to send secured messages in the digital signature and the law of e-commerces. Our paper shows a H-binary tree of time stamp to use a time stamp protocol with high security and performance in the packets of sending messages. We implement and analyze the protocols, show to compare with previous RSA methods. Our proposed protocol has O(log n) time complexity and high-performance.

• 전기전자학회논문지
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• 제17권2호
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• pp.159-162
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• 2013

본 논문에서는 SOAP(Simple Object Access Protocol)에 대하여 JAVA와 .NET 두 가지 플랫폼에 따른 성능 분석을 수행한다. SOAP는 다양한 전송 계층 프로토콜을 이용할 수 있는데, 본 논문에서는 HTTP, TCP, UDP를 이용하여 성능 분석 방법을 제안하고 제안한 방법을 토대로 성능 분석을 실시하였다. 성능 분석 결과는 시스템 환경 및 네트워크 부하 정도에 따라 다르게 도출될 수 있다. 따라서 정확한 성능 분석을 위해 동일한 환경을 구축하여 진행하였다.

• 한국정보과학회논문지:정보통신
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• 제29권5호
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• pp.543-552
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• 2002

Wireless Application Protocol(WAP) 포럼에서는 무선 환경의 특성에 적합하도록 HyperText Transfer Protocol(HTTP)를 수정 보완한 Wireless Session Protocol(WSP)를 제안하였다 WSP는 무선 구간에서의 프로토콜 성능을 상당부분 개선하였고, 무선 환경을 고려한 다양한 서비스를 제공하고 있다. 본 논문에서는 기존의 WSP에 프로토콜 메시지 압축 기능을 추가하여 기존 프로토콜의 성능을 더욱 개선하였다. 그리고, 기존의 WSP 구현물과 프로토콜 메시지 압축 기능을 추가한 WSP+ 구현물의 성능을 측정하고 비교하였다. 그 결과 본 논문에서 제안한 프로토콜 메시지 압축기능은 기존 WSP에 비하여 응답 트래픽을 약 45% 감소시켰다. 그리고, 비트 오류 발생률이 $10^{-4}$인 실험 환경에서 패킷 손실률과 트랜잭션당 시간 지연을 40% 이상 개선하였다. 이러한 측정 결과에서 알 수 있듯이, 프로토콜 메시지 압축 기능은 무선 구간에서 전달되는 메시지의 크기를 줄임으로써 패킷의 손실률을 낮추어 트랜잭션 계층에서의 메시지 재전송 횟수를 줄이고 트랜잭션당 시간 지연을 단축하였다.

• Journal of information and communication convergence engineering
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• 제12권4호
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• pp.199-207
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• 2014

A new cooperative MAC protocol called the busy tone cooperative medium access control (BT-COMAC) protocol is proposed to overcome the drawbacks and maximize the advantages of existing schemes. This scheme uses a new metric called decibel power to decide an appropriate helper node. Using received power strength is more efficient in selecting an appropriate helper node, especially in a densely populated network, than the effective transmission rates used in conventional schemes. All communication nodes in a communication service area are assumed to move independently. Two performance metrics are used: System throughput and channel access delay. A performance evaluation of the BT-COMAC protocol is conducted using a computer simulation over a slow fading wireless channel, and its performance results are compared with those of four existing schemes. The numerical results show that the BT-COMAC protocol improves the system throughput by approximately 15% as compared to the best existing scheme.

• 한국IT서비스학회지
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• 제12권4호
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• pp.349-367
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• 2013

In MANET, the AODV routing protocol with on-demand method has a problem in large control packet overhead. In order to improve this, we first need a comprehensive analysis of correlation between performance metrics and factors affecting the performance of AODV. Selected parameters based on this analysis make it enable to be a more accurate and fair performance analysis, as well as to reduce the time and effort when constructing a scenario for performance analysis. In this paper, various scenarios are configured to apply AODV by varying the values of factors affecting the performance with network simulator QualNet 5.0, and then the results are analysed using performance metrics proposed by IETF MANET working group. This paper also founds a correlation between performance metrics and factors affecting the performance for AODV routing protocol, choosing the values of factors that represent many of the most maximum and minimum values of each performance metrics, and proposes optimal simulation parameters for a more accurate performance evaluation of routing protocols with minimal scenario in experiments. Next, performance comparison of AODV, DSR and DYMO routing protocols based on the proposed simulation parameters is shown which provides a comparative analysis on the performance of on-demand routing protocols. Results of this paper could be very useful for the researcher or service provider who wants to find nice simulation environment or select a proper routing protocol.

• International journal of advanced smart convergence
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• 제5권1호
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• pp.8-15
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• 2016

Studies have been made for the wireless sensor network protocols by a number of researchers to date. In particular, the studies as to the hierarchical protocol LEACH algorithm was concentrated. Various studies have been derived for the performance of the protocol is based on the LEACH protocol have been made. Improved algorithms have been proposed continuously. On the other hand, The performance comparison and evaluation of the improved algorithm is insufficient. Therefore, we compared the performance for the ML-LEACH (Multi Hop-Layered) and DL-LEACH (Dual Hop-Layered) been derived mainly LEACH. scalability, energy consumption, CH elected, network lifetime were selected as a Performance evaluation items.