첨단 연구 망(KOREN)에서의 병렬 전송 성능 분석

김영신;허의남 서울여자대학교 컴퓨터과학연구소 2004 정보기술논문지 Vol.2 No.-

한 호스트에서 네트워크 상으로 데이터를 전송할 경우에 bandwidth나 bottleneck등의 네트워크의 환경 요소, 트래픽 양과 같은 네트워크 상황, 그리고 호스트의 성능에 따라 전송 속도가 달라질 수 있다. 따라서 데이터 전송 능력을 향상시키기 위해 연구되고 있는 TCP buffer tuning 와 parallel sockets와 같은 기술들을 이러한 요소들을 효율적으로 이용함으로써 그 효과를 얻고 있다. 그러나 연구의 대부분이 네트워크의 환경 요소나 상황을 중심으로 연구되고 있는 실정으로 호스트 성능에 대해서는 고려되지 않고 있다. 게다가 병렬 전송 시 호스트 시스템 성능과 데이터 전송 능력과의 관계 분석은 미진한 편이다. 따라서 본 논문에서는 네트워크 성능 향상 기법 중에 하나인 parallel sockets를 이용하여 데이터를 전송할 경우 호스트의 상태를 실험을 통하여 조사하였으며, 이를 바탕으로 호스트 성능이 데이터 전송 능력과의 관계를 분석하였다. 본 실험에서 시스템의 성능이 데이터 전송 능력에는 큰 영향을 미치지 못하며, 네트워크의 부하에 의해서 발생되는 시스템의 부하가 여러 개의 channel로 인해 발생된 시스템 부하 보다 더 크게 영향을 미친다는 것을 알 수 있었다. The end-to-end data transmission times between two hosts are various by network environment elements, network condition, and the performance of the host. The method -TCP buffer tuning and parallel sockets- studied to improve of data transmission ability. Those methods can obtain improvement of the data transmission performance by appling those elements more efficiently. However, in the present time, most researchers consider with network environment elements and condition while on the other they don't consider a performance of the host. Furthermore, in the relation analysis ??? studies between the performance of a system and data transmission time the week. In this paper, we measure a load of the send side host system in case of data transmission through the Parallel sockets. And we analyzed the relationship between the performance of host system and data transmission ability by collecting results of experimental. Finally, we observed that the system overhead does not affect data transmission rate, and overall performance is dependent on network load rattier than system load.

초고속망에서 네트워크 성능 최적화를 위한 TCP 버퍼 튜닝 도구 설계 및 구현

김영신,허의남 서울여자대학교 컴퓨터과학연구소 2003 정보기술논문지 Vol.1 No.-

네트워크 최적화를 위해 네트워크의 현재 상태를 파악하여야만 하는데, 이 때 네트워크 측정 툴을 사용한다. 기존의 네트워크 측정 툴은 측정을 위한 메시지를 전송하고 전송된 데이터양과 전송시간 등을 이용하여 네트워크 상태를 분석하였다. 그러나 이러한 툴들은 네트워크 상태를 분석한 후, 분석 결과에 따라 사용자가 데이터양을 조절하는 등의 액션을 취하여 최적의 네트워크 상태를 만들었다. 그러나 본 논문에서는 데이터 전송 시간의 지연이 호스트 내부(TCP buffer 크기)에서도 발생함을 실험을 통해 증명하였다. 또한, 네트워크 측정 결과를 이용하여 TCP buffer의 크기를 계산하고 조절(튜닝)함으로써 (TCP buffer에 전송될 데이터가 쌓이는 속도와 데이터 전송 속도의 밸런스를 맞춤) 더 나은 네트워크 성능을 보이게 됨을 증명하였다. 이에 본 논문에서는 TCP buffer의 크기를 조절함으로써 최상의 네트워크 성능을 만들 수 있는 툴을 설계하고 구현하였다. We have to know state of a network for optimization of a network. At that time, we use a network monitoring tool to know network traffic. Most network monitoring tools are used to analyse performance of network. They send a few messages and measure bandwidth and delay. But these tools help applications to utilize network capacity efficiently with the current metrics or parameters as the result of network analysis is enough to coordinate network status to be reliable and efficient. This paper shows experimentally that data transmission delay occurred in host side much larger than network side. Also, we measure performance of network and use the result to compute optimized TCP buffer size in order to fit balance between the speed that a data are piled up in TCP buffer and data transmission speed. So, in this paper we design and implement a network optimization tool using TCP buffer tuning.

Application Driven Cluster Based Group Key Management with Identifier in Mobile Wireless Sensor Networks

( Eui-nam Huh ),( Nahar Sultana ) 한국인터넷정보학회 2007 KSII Transactions on Internet and Information Syst Vol.1 No.1

This paper proposes and analyzes a scalable and an efficient cluster based group key management protocol by introducing identity based infrastructure for secure communication in mobile wireless sensor networks. To ensure scalability and dynamic re-configurability, the system employs a cluster based approach by which group members are separated into clusters and the leaders of clusters securely communicate with each other to agree on a group key in response to changes in membership and member movements. Through analysis we have demonstrated that our protocol has a high probability of being resilient for secure communication among mobile nodes. Finally, it is established that the proposed scheme is efficient for secure positioning in wireless sensor networks.

Application Driven Cluster Based Group Key Management with Identifier in Mobile Wireless Sensor Networks

Huh, Eui-Nam,Nahar Sultana Korean Society for Internet Information 2007 KSII Transactions on Internet and Information Syst Vol.1 No.1

This paper proposes and analyzes a scalable and an efficient cluster based group key management protocol by introducing identity based infrastructure for secure communication in mobile wireless sensor networks. To ensure scalability and dynamic re-configurability, the system employs a cluster based approach by which group members are separated into clusters and the leaders of clusters securely communicate with each other to agree on a group key in response to changes in membership and member movements. Through analysis we have demonstrated that our protocol has a high probability of being resilient for secure communication among mobile nodes. Finally, it is established that the proposed scheme is efficient for secure positioning in wireless sensor networks.

An Efficient Statistical Profile Technique for Monitoring of Grid Applications

Eui-Nam Huh,Hyoung-Woo Park 한국산업응용수학회 2002 Journal of the Korean Society for Industrial and A Vol.6 No.1-1

Performance enhancement of TCP in high-speed networks

Huh, Eui-Nam,Choo, Hyunseung Elsevier 2008 Information sciences Vol.178 No.2

<P><B>Abstract</B></P><P>GridFTP is a secure and reliable high-performance parallel data transfer protocol used for transferring massive amounts of widely distributed data. Currently it allows users to configure the number of parallel streams and socket buffer size. However, its tuning procedure for optimal combination is a time consuming task. The socket handlers and buffers are important system resources and must therefore be carefully managed. In this paper, we propose a scheme to achieve high throughput even with a smaller buffer size, and also derive a regression equation to predict the optimal combination of resources for a connection. To improve the performance, the TCP based on our scheme obtains higher throughput and spends less memory for the same throughput than the original TCP scheme. In addition, the regression equation is verified by comparing measured and predicted values, and we apply the equation to an actual experiment on the KOrea advanced REsearch Network (KOREN). The result demonstrates that the equation provides excellent predictions with only an 8% error boundary.</P>

적응형 그리드 시스템를 위한 이질적인 자원 관리

허의남(Eui-Nam Huh),이웅재(Woongjae Lee),이종숙(Jong Suk Lee) 한국시뮬레이션학회 2004 한국시뮬레이션학회 논문지 Vol.12 No.4

Real-Time applications on Grid environment have several problems in terms of resource management addressed as follows;(1) dynamic resource allocation to provide QoS objectives, (2) heterogeneous resources that is different scale, or capacity in same unit, and (3) resource availability, and resource needs. This paper describes the techniques of resource manager (RM) handling above problems to support QoS of dynamic real-time applications on Grid. The contributions of this paper to solve problems are as follows: unification of dynamic resource requirements among heterogeneous hosts, control of resources in heterogeneous environments, and dynamic load balancing/sharing. Our heuristic allocation scheme works not only 257% better than random, 142% better than round robin, and 36.4% better than least load in QoS sensitivity, but also 38.6% better than random, 28.5% better than round robin, and 31.6% better than least load in QoS.

Effects of altering medium strength and sucrose concentration on in vitro germination and seedling growth of Cypripedium macranthos Sw.

Huh, Yoon Sun,Lee, Joung Kwan,Nam, Sang Young,Hong, Eui Yon,Paek, Kee Yoeup,Son, Sung Won The Korean Society of Plant Biotechnology 2016 식물생명공학회지 Vol.43 No.1

The genus Cypripedium, known as lady's slipper orchid, has been considered to have a considerable marketability as a potted and garden plant with beautiful flowers; however, this species is becoming endangered and, in some places extinct, due to habitat destruction and illegal collections. As such, an optimized artificial propagation system is necessary for its conservation and horticultural cultivation. For the establishment of the in vitro proliferation of the endangered Cypripedium macranthos Sw., native to Korea, the effects of medium strength and sucrose concentrations on germination, protocorm formation and seedling growth were investigated through asymbiotic seed culture. The highest germination rate and protocorm formation rate were obtained with a 1/4 MS medium; higher MS medium strengths did not generate the favorable conditions required for germination and protocorm growth. The overall growth characteristics of roots and buds developed from protocorms were best in cultures of 1/4 MS medium. On this medium containing $10g{\cdot}L^{-1}$ sucrose, both the germination rate and protocorm formation rate increased significantly. The general growth properties of seedlings developed on the medium with $10g{\cdot}L^{-1}$ sucrose were best, showing the highest bud formation rate and root number. Our results demonstrate that the 1/4 MS medium, supplemented with $10g{\cdot}L^{-1}$ sucrose, could improve in vitro germination, and facilitate the growth of seedlings developed from the protocorms of C. macranthos Sw.

A new hybrid model for topic-based publish/subscribe systems

Van-Nam Pham(팜반남),Aymen Abdullah Alsaffar(아이만 압둘라 알사파르),Eui-Nam Huh(허의남) 한국정보과학회 2016 한국정보과학회 학술발표논문집 Vol.2016 No.6

A Low-Delay Broker Model Underlaying IoT Applications

Van-Nam Pham,VanDung Nguyen,Young-Rok Shin,Eui-Nam Huh 한국정보과학회 2018 한국정보과학회 학술발표논문집 Vol.2018 No.12