• Title/Summary/Keyword: Traffic Congestion Control

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A Study on the Traffic Controller of ATM Call Level Based on On-line Learning (On-line 학습을 통한 ATM 호레벨 트래픽 제어 연구)

  • 서현승;백종일;김영철
    • Proceedings of the IEEK Conference
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    • 2000.06a
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    • pp.115-118
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    • 2000
  • In order to control the flow of traffics in ATM networks and optimize the usage of network resources, an efficient control mechanism is necessary to cope with congestion and prevent the degradation of network performance caused by congestion. To effectively control traffic in UNI(User Network Interface) stage, we proposed algorithm of integrated model using on-line teaming neural network for CAC(Call Admission Control) and UPC(Usage Parameter Control). Simulation results will show that the proposed adaptive algorithm uses of network resources efficiently and satisfies QoS for the various kinds of traffics.

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Congestion Control for the ABR Service of ATM networks with Multiple Congested Nodes and Multicast Connections (다수의 혼잡 노드와 멀티개스트 연결을 가지는 비동기 전송망의 ABR 서비스에 대한 혼잡 제어)

  • Nho, Ji-Myong;Lim, Jong-Tae
    • Journal of Institute of Control, Robotics and Systems
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    • v.6 no.8
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    • pp.629-637
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    • 2000
  • Unbalance between user requirements and insufficient network resources makes a congestion. In the future since the communication networks will have very heavy traffic congestion will be more serious. The ATM networks was recommended to support the B-ISDN service for the future multimedia communication. In thie sense of congestion avoidance and recovery the ABR service category in ATM networks allows the feedback flow control mechanism to dynamically allocate the idle bandwidth of the network to users fairly and to control the network congestion rapidly In this paper we introduce a congestion control scheme using systematical approach to confirm robust stability with respect to unknown round trip delay for the network which has both unicast and multicast connections.

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Measurement of RTT for TCP Congestion Control (TCP 혼잡제어를 위한 RTT(Round trip time) 측정)

  • Kim, Eun-Gi
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.5
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    • pp.1520-1524
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    • 2000
  • TCP congestion control algorithm prevents network congestion through the control of outgoing traffic size. The network, therefore, should monitor the incoming traffic size of a TCP to determine whether or not a TCP follows standard congestion control algorithms. Some TCP friendly test algorithms are proposed, But, these algorithms cannot be used in real environments because a router in a network does not know the RTT of a TCP flow. In this study, we propose a new RTT determination algorithm that can be used in a router. Our proposed algorithms is validated through the simulation studies.

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An improved performance of TCP traffic connection congestion control in wireless networks (무선네트워크에서 TCP 트래픽 연결 혼잡제어에 관한 성능 개선)

  • Ra Sang-dong;Na Ha-sun;Park Dong-suk
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.2
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    • pp.264-270
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    • 2006
  • In this paper we verified that the window based TCP performance of throughput can be improved by the traffic connection efficiency. and have studied the performance of traffic congestion control that is controlling transmission rate. In wireless network, the bidirectional node is run by estimating the usage rate of link of error control idle and the throughput is shown by transmitting segments. The throughput rate shows almost no delay due to the bidirectional traffic connection efficiency up to the allowable point as increasing the transport rate by the critical value, depending on the size of end-to-end node queue of the increase of transport rate. This paper reports the performance improvement as the number of feedback connection traffic congestion control increases because of the increase of the number of asynchronous transport TCP connections.

A development of traffic information detection using camera

  • 김양주;한민홍
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1995.04a
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    • pp.316-323
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    • 1995
  • This paper presents an image processing technique to get traffic information such as vehicle volume, velocity, and occupancy for measuring the traffic congestion rate. To obtain these information, two horizontal lines are previously set on the screen. A moving vehicle is detected using the gray level difference on each line, and also template matching method at night. Threshold values are determined by sampling pavement grey level, and updated dynamically to cope with the change of ambient light conditions. These technique is successfully used to calculate vehicle volume, occupancy, and velocity. This study can be applied to traffic signal control system for minimizing traffic congestion in urban areas.

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Simulation of Traffic Signal Control with Adaptive Priority Order through Object Extraction in Images (영상에서 객체 추출을 통한 적응형 통행 우선순위 교통신호 제어 시뮬레이션)

  • Youn, Jae-Hong;Ji, Yoo-Kang
    • Journal of Korea Multimedia Society
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    • v.11 no.8
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    • pp.1051-1058
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    • 2008
  • The advancement of technology for image processing and communications makes it possible for current traffic signal controllers and vehicle detection technology to make both emergency vehicle preemption and transit priority strategies as a part of integrated system. Present]y traffic signal control in crosswalk is controlled by fixed signals. The signal control keeps regular signals traffic even with no traffic, when there is traffic, should wait until the signal is given. Waiting time causes the risk of traffic accidents and traffic congestion in accordance with signal violation. To help reduce the risk of accidents and congestion, this paper explains traffic signal control system for the adaptive priority order so that signal may be preferentially given in accordance with the situation of site through the object detect images.

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Dynamic Traffic Light Control Scheme Based on VANET to Support Smooth Traffic Flow at Intersections (교차로에서 원활한 교통 흐름 지원을 위한 VANET 기반 동적인 교통 신호등 제어 기법)

  • Cha, Si-Ho;Lee, Jongeon;Ryu, Minwoo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.18 no.4
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    • pp.23-30
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    • 2022
  • Recently, traffic congestion and environmental pollution have occurred due to population concentration and vehicle increase in large cities. Various studies are being conducted to solve these problems. Most of the traffic congestion in cities is caused by traffic signals at intersections. This paper proposes a dynamic traffic light control (DTLC) scheme to support safe vehicle operation and smooth traffic flow using real-time traffic information based on VANET. DTLC receives instantaneous speed and directional information of each vehicle through road side units (RSUs) to obtain the density and average speed of vehicles for each direction. RSUs deliver this information to traffic light controllers (TLCs), which utilize it to dynamically control traffic lights at intersections. To demonstrate the validity of DTLC, simulations were performed on average driving speed and average waiting time using the ns-2 simulator. Simulation results show that DTLC can provide smooth traffic flow by increasing average driving speed at dense intersections and reducing average waiting time.

LSP Congestion Control methods in ATM based MPLS on BcN

  • Kim Chul soo;Park Na jung;Ahn Gwi im;Lee Jung tae
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.4A
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    • pp.241-249
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    • 2005
  • ATM based MPLS(Multiprotocol Label Switching) is discussed for its provisioning QOS commitment capabilities, Traffic engineering and smooth migration for BcN in Korea. At this time, due to the comprehensive nature of ATM protocol, ATM has been adapted as the backbone system for carrying Internet traffic[1,2,3,4]. This paper presents preventive congestion control mechanisms for detecting HTR(Hard-To-Reach) LSP(Label Switched Path) in ATM based MPLS systems. In particular, we have introduced a HTR LSP detection method using network signaling information in an ATM layer. MPLS related studies can cover LSP failures in a physical layer fault, it can not impact network congestion status. Here we will present the research results for introducing HTR LSP detection methods and control mechanisms and this mechanism can be implementing as SOC for high speed processing a packet header. We concluded that it showed faster congestion avoidance abilities with a more reduced system load and maximized the efficiency of network resources by restricting ineffective machine attempts.

A Study on an Adaptive UPC Algorithm Based on Traffic Multiplexing Information in ATM Networks (ATM 망에서 트래픽 다중화 정보에 의한 적응적 UPC 알고리즘에 관한 연구)

  • Kim, Yeong-Cheol;Byeon, Jae-Yeong;Seo, Hyeon-Seung
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.10
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    • pp.2779-2789
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    • 1999
  • In this paper, we propose a new neural Buffered Leaky Bucket algorithm for preventing the degradation of network performance caused by congestion and dealing with the traffic congestion in ATM networks. We networks. We justify the validity of the suggested method through performance comparison in aspects of cell loss rate and mean transfer delay under a variety of traffic conditions requiring the different QoS(Quality of Service). also, the cell scheduling algorithms such as DWRR and DWEDF used for multiplexing the incoming traffics are induced to get the delay time of the traffics fairly. The network congestion information from cell scheduler is used to control the predicted traffic loss rate of Neural Leaky Bucket, and token generation rate is changed by the predicted values. The prediction of traffic loss rate by neural networks can effectively reduce the cell loss rate and the cell transfer delay of next incoming cells and be applied to other traffic control systems. Computer simulation results performed for traffic prediction show that QoSs of the various kinds of traffics are increased.

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A Study on TCP Efficiency Improvements from Network Mobile Environment (네트워크 이동 환경에서의 TCP 성능 향상에 관한 연구)

  • Cho, Hyun-Seob
    • Proceedings of the KAIS Fall Conference
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    • 2011.05a
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    • pp.375-378
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    • 2011
  • 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.

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