• 제목/요약/키워드: Congestion Information

검색결과 1,193건 처리시간 0.024초

3차원 메쉬에 대한 완전 이진트리의 링크 충돌없는 임베딩 (Link-Disjoint Embedding of Complete Binary Trees in 3D-Meshes)

  • 이주영;이상규
    • 한국정보과학회논문지:시스템및이론
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    • 제30권7_8호
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    • pp.381-386
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    • 2003
  • 본 논문에서는 완전이진트리의 3차원 메쉬로의 임베딩 문제를 다룬다. 링크 충돌을 2까지 허용하면서 최적크기의 메쉬에 임베딩하는 방법은 [1]에서 다루고 있으며, [2]에서는 최적크기의 1.27배의 메쉬로 임베딩하는 방법을 보여주고 있다. 본 논문에서 제안하는 임베딩 방법은 순위차원 라우팅을 사용하며 링크 충돌이 없는 방법으로, 약 1.125배의 최적확장을 넘지 않는다. 이 임베딩 방법은 링크의 충돌 혹은, 임베딩의 확장을 최소화한다는 기준에서 볼 때 기존의 임베딩 방법에 비해 향상된 결과이다.

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

  • 서현승;백종일;김영철
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(1)
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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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IP기반 MPLS망의 성능향상을 위한 Advanced LER (Advanced LER to Improve Performance of IP over MPLS)

  • 박성진;김진무;이병호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 추계종합학술대회 논문집(1)
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    • pp.37-40
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    • 2000
  • Multi Protocol Label Switching (MPLS) is a high performance method for forwarding packets (frames) through a network. It enables routers at the edge of a network to apply simple labels to packets (frames). we use MPLS in the core network for internet. MPLS provide high speed switching and traffic engineering in MPLS domain but at the Label Edge Router(LER) there is frequently cell discarding via congestion and buffer management method. It is one of the most important reasons retransmission and congestion. In this paper we propose advanced LER scheme that provide less cell loss rate also efficient network infrastructure.

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후위순회 피보나치 원형군에 대한 임베딩 (The Embddings on Postorder Fibonacci Circulants)

  • 김용석;권승탁
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 하계종합학술대회 논문집(1)
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    • pp.163-166
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    • 2004
  • In this paper, we consider the embedding problem of postorder Fibonacci circulants. We show that Fibonacci cubes and Hypercube are a subgraph of postorder Fibonacci circulants. And the postorder Fibonacci circulants of order n can be embedded into the Fibonacci cubes of order n with expansion 1, dilation n-2 and congestion O (n-1), the Hypercube of order n-2 with expansion $\frac{f_n}{2^{n-2}}$, dilation n-2 and congestion O(n-2).

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ATM ABR 서비스에서 큐 길이 변화를 이용한 개선된 폭주 제어 알고리즘 (Advanced Congestion Control Algorithm Using Change of Queue Length in ATM ABR Service)

  • 김체훤;강현철;곽지영;남지승
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(3)
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    • pp.109-112
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    • 2000
  • The EPRCA(Enhanced Proportional Rate Control Algorithm) is one of the explicit rate control algorithm recommended by the ATM forum. EPRCA algorithm is using only two threshold to buffer change is not considered for calculating ER value. In this paper to cover the shortage, two more variables are added for considering increase of buffer quantity. So calculating proper ER would avoid before getting into the congestion situation. To analysis the affect, EPRCA and proposed algorithm are compared through simulation by analysis of change of buffer length and ACR change

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Queue Management using Optimal Margin method to Improve Bottleneck Link Performance

  • Radwa, Amr
    • 한국멀티미디어학회논문지
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    • 제18권12호
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    • pp.1475-1482
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    • 2015
  • In network routers, buffers are used to resolve congestion and reduce packet loss rate whenever congestion occurs at bottleneck link. Most of the existing methods to manage such buffers focus only on queue-length-based control as one loop which have some issues of low link utilization and system stability. In this paper, we propose a novel framework which exploits two-loop control method, e.g. queue-length and congestion window size, combined with optimal margin method to facilitate parameter choices. Simulation results in ns-2 demonstrate that bottleneck link performance can be improved with higher link utilization (85%) and shorter queue length (22%) than the current deployed scheme in commercial routers (RED and DropTail).

무선 환경에서 802.11 MAC의 MIB 정보를 이용한 TCP 성능 개선 (TCP Performance Improvement using 802.11 MAC MIB for Wireless Network)

  • 김기원;신광식;윤완오;최상방
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.59-60
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    • 2006
  • TCP applied to the wireless-wired integrated network is the one that was applied to the existing wired network. In the wireless-wired integrated network, both wireless and congestion loss can occur. When wireless packet losses occur, the congestion control of TCP causes performance degradation by reducing its transmission rate. In this paper, we propose the algorithm to distinguish the wireless packet loss from congestion packet loss using MIB of the 802.11 MAC which has been generally used recently in wireless links.

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이종 트래픽 다중 처리 시스템의 폭주제어에 관한 연구 (A Study on the Congestion Control in the Integrated Heterogeneous Traffic Multiplexer)

  • 홍성백;심철;박민용;이상배
    • 전자공학회논문지B
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    • 제28B권10호
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    • pp.790-798
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    • 1991
  • The congestion control methods of an integrated heterogeneous traffic multiplexer are studied. The real-time traffics have preemptive priority over nonreal-time traffics in capturing the common output link. Also real-time traffics are transmitted with bandwidth reduction when the nonreal-time traffics are over the buffer threshold. The proposed model formulated the system as a continous time Markov process and is analysed using matrix equation. Time delay and average number of used channel are applied for performance parameters. In this study, a new control method with the sizable buffer threshold is introduced and the optimal congestion control can be obtained.

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Instantaneous Fairness of TCP in Heterogeneous Traffic Wireless LAN Environments

  • Jung, Young-Jin;Park, Chang Yun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권8호
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    • pp.3753-3771
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    • 2016
  • Increasingly, numerous and various Internet-capable devices are connected in end user networks, such as a home network. Most devices use the combination of TCP and 802.11 DCF as a system platform, but whereas some devices such as a streaming video persistently generate traffic, others such as a motion sensor do so only intermittently with lots of pauses. This study addresses the issue of performance in this heterogeneous traffic wireless LAN environment from the perspective of fairness. First, instantaneous fairness is introduced as a notion to indicate how immediately and how closely a user obtains its fair share, and a new time-based metric is defined as an index. Second, extensive simulation experiments have been made with TCP Reno, Vegas, and Westwood to determine how each TCP congestion control corresponds to the instantaneous fairness. Overall, TCP Vegas yields the best instantaneous fairness because it keeps the queue length shorter than the other TCPs. In the simulations, about 60% of a fair share of the effective user bandwidth is immediately usable in any circumstance. Finally, we introduce two simple strategies for adjusting TCP congestion controls to enhance instantaneous fairness and validate them through simulation experiments.