• Title/Summary/Keyword: round trip time

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Development of an Optimized Prediction System of Round Trip Occurrence using Genetic Algorithm (유전자알고리즘을 활용한 최적화된 라운드트립 발생 예측 시스템 개발)

  • Lee, Seung Soo;Seo, Jong Won;Kim, Kwang Yeom;Shin, Hyu-Soung
    • Tunnel and Underground Space
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    • v.25 no.6
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    • pp.534-542
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    • 2015
  • Round trip activity occurs discretely due to the abrasion of drill bit in the deep drilling project. Round trip has great impact on the drilling performance because it takes more time to change a drill bit as the depth goes deeper. Therefore, a reliable prediction technology of the round trip should be secured for feasibility analysis and effective management of the drilling project. Lee et al. (2013) developed the TOSA (round trip occurrence simulation algorithm) which can analyze the depth and timing of round trip occurrence at each abrasion state of bit. However, TOSA has weakness that it takes long time for simulation because the number of simulation increase exponentially as increasing the number of simulation section. This study developed the TOSA based round trip performance prediction module using genetic algorithm for simulating in a short time and verified simulation results.

One-Way Delay Estimation Using One-Way Delay Variation and Round-Trip Time (단방향 지연 변이와 일주 지연을 이용한 양단간의 단방향 지연 추정)

  • Kim, Dong-Keun;Lee, Jai-Yong
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.1
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    • pp.175-183
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    • 2008
  • QoS-support technology in networks is based on measuring QoS metrics which reflect a magnitude of stability and performance. The one-way delay measurement of the QoS metrics especially requires a guarantee of clock synchronization between end-to-end hosts. However, the hosts in networks have a relative or absolute difference in clock time by reason of clock offsets. flock skews and clock adjustments. In this paper, we present a theorem, methods and simulation results of one-way delay and clock offset estimations between end-to-end hosts. The proposed theorem is a relationship between one-way delay, one-way delay variation and round-trip time And we show that the estimation error is mathematically smaller than a quarter of round-trip time.

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Analysis of internet self-similar traffic through the round-trip time measurement (Round-Trip Time 측정을 통한 인터넷 트래픽의 자기 유사성 분석)

  • 황인수;송기평;이동철;박기식;김창호;김동일;최삼길
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.11a
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    • pp.326-330
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    • 1999
  • 인터넷의 민감한 트래픽 특성으로 인해 기존의 트래픽 모델링 분석법으로 최적화된 네트워크 환경을 구성하기에는 부족한 점이 많다. 본 논문에서는 트래픽의 버스트 특성을 정확히 예측하고 모델링 하기 위한 방법으로 자기 유사 특성에 대해 분석하고자 한다. 실제 인터넷 네트워크에서의 RTT(Round-Trip Time)를 측정함으로써 계층, 거리별 링크간의 LRD(Long-Range Dependence) 와 노드 큐의 특성, 자기유사성 정도를 구하고 측정된 데이터의 확률 분포를 통해 실제 트래픽의 특성에 대해 분석하였다

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A Study on Conversion Between UML and Source Code Based on RTT(Round-Trip Translator) (RTT(Round-Trip Translator) 기반의 UML과 소스코드 변환에 대한 연구)

  • Kim, Ji Yong;Cho, Han Joo;Kim, Young Jong
    • KIPS Transactions on Software and Data Engineering
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    • v.8 no.9
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    • pp.349-354
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    • 2019
  • s programming education becomes more important in recent years, it is necessary to learn how the source code written by students reflects Object-Oriented(OO) concepts. We present a tool called the Round-Trip Translator(RTT) that transforms the Unified Modeling Language(UML) class diagram and Java source code to provide a web-based environment that provides real-time synchronization of UML and source code. RTT was created by improving existing RTE and is a tool for students who are learning OO concepts to understand how their UML or source code reflects the concepts that user intended. This study compares the efficiency and user- friendliness of RTT with the existing Round-Trip Engineering-based tools. The results show that students have improved understanding of OO concepts through UML and source code translation by using the RTT. We also found out that students were satisfied with the use of the RTT, which provides more efficient and convenient user interface than the existing tools.

Design of a High-Performance Web Crawler Considering the Round Trip Time (왕복시간(Round Trip Time)을 고려한 고성능 웹크롤러 설계)

  • Jeong, Chun-Ho;Cho, Hyun-Tae;Beak, Yun-Ju
    • Proceedings of the Korea Information Processing Society Conference
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    • 2004.05a
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    • pp.601-604
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    • 2004
  • 인터넷과 정보기술의 급속적인 발전으로 수천 또는 수억에 달하는 방대하고 다양한 정보들이 웹 상에서 존재하게 되었다. 이러한 다양한 정보들 중에서 이용자가 원하는 정보를 제공하기 위해 다양한 검색시스템들이 개발되었다. 웹 크롤러는 검색시스템의 중요한 부분 중의 하나로, 웹 서버를 순회하며 각 페이지에 있는 수많은 정보를 수집하는 프로그램이다. 본 논문에서는 웹 크롤러의 기본요건 중의 하나인 빠른 수집속도를 보장하기 위해 RTT(Round Trip Time) Scheduling 기법을 적용한 URL 스케줄러를 제시하고, 이러한 RTT Scheduling 기법을 이용한 웹 크롤러를 설계한다.

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A Localization Using Multiple Round Trip Times in Wireless Sensor Networks (무선 센서 네트워크에서 다중 왕복시간차를 이용한 위치측정)

  • Jang, Sang-Wook;Ha, Rhan
    • Journal of KIISE:Information Networking
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    • v.34 no.5
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    • pp.370-378
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    • 2007
  • In wireless sensor networks (WSNs), thousands of sensors are often deployed in a hostile environment. In such an environment, WSNs can be applied to various applications by using the absolute or relative location information of the sensors. Until now, the time-of-arrival (TOA) based localization method has been considered most accurate. In the TOA method, however, inaccuracy in distance estimation is caused by clock drift and clock skew between sensor nodes. To solve this problem, several numbers of periodic time synchronization methods were suggested while these methods introduced overheads to the packet traffic. In this paper, we propose a new localization method based on multiple round-trip times (RTOA) of a signal which gives more accurate distance and location estimation even in the presence of clock skew between sensor nodes. Our experimental results show that the Proposed RTOA method gives up to 93% more accurate location estimation.

DDoS attacks prevention in cloud computing through Transport Control protocol TCP using Round-Trip-Time RTT

  • Alibrahim, Thikra S;Hendaoui, Saloua
    • International Journal of Computer Science & Network Security
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    • v.22 no.1
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    • pp.276-282
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    • 2022
  • One of the most essential foundations upon which big institutions rely in delivering cloud computing and hosting services, as well as other kinds of multiple digital services, is the security of infrastructures for digital and information services throughout the world. Distributed denial-of-service (DDoS) assaults are one of the most common types of threats to networks and data centers. Denial of service attacks of all types operates on the premise of flooding the target with a massive volume of requests and data until it reaches a size bigger than the target's energy, at which point it collapses or goes out of service. where it takes advantage of a flaw in the Transport Control Protocol's transmitting and receiving (3-way Handshake) (TCP). The current study's major focus is on an architecture that stops DDoS attacks assaults by producing code for DDoS attacks using a cloud controller and calculating Round-Tripe Time (RTT).

A Solution for Timing Gap Problems on Network Intrusion Detection Systems (네트워크 침입 탐지 시스템에서의 시차 문제 해결 방안)

  • 차현철
    • Journal of Korea Society of Industrial Information Systems
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    • v.6 no.1
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    • pp.1-6
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    • 2001
  • This paper proposes a method to reduce the timing gap which causes a type of attack to a network-based intrusion detection system. For this, an intrusion defection system is used in order to measure the round trip tin to the destination system, and the measured round trip time is used for estimation of packet's real arrival time to destination. Socket programings are used on the LAN environments to evaluate the performance of the proposed method. The test results show that an estimation method which uses the latest round trip time has the best performance, and the timing gap can be significantly reduced with small overheads.

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Long-Range Dependence and 1/f Noise in a Wide Area Network Traffic (광역 네트워크 트래픽의 장거리 상관관계와 1/f 노이즈)

  • Lee, Chang-Yong
    • Journal of KIISE:Information Networking
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    • v.37 no.1
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    • pp.27-34
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    • 2010
  • In this paper, we examine a long-range dependence in an active measurement of a network traffic which has been a well known characteristic from analyses of a passive network traffic measurement. To this end, we utilize RTT(Round Trip Time), which is a typical active measurement measured by PingER project, and perform a relevant analysis to a time series of both RTT and its volatilities. The RTT time series exhibits a long-range dependence or a 1/f noise. The volatilities, defined as a higher-order variation, follow a log-normal distribution. Furthermore, volatilities show a long-range dependence in relatively short time intervals, and a long-range dependence and/or 1/f noise in long time intervals. From this study, we find that the long-range dependence is a characteristic of not only a passive traffic measurement but also an active measurement of network traffic such as RTT. From these findings, we can infer that the long-range dependence is a characteristic of network traffic independent of a type of measurements. In particular, an active measurement exhibits a 1/f noise which cannot be usually found in a passive measurement.