• 제목/요약/키워드: Congestion

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네트워크 효율 향상을 위한 개선된 TCP 혼잡제어 알고리즘 (Modified TCP Congestion Control Algorithm to Improve Network Efficiency)

  • 최지현;김대영;김관웅;정경택;전병실
    • 대한전자공학회논문지TC
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    • 제40권8호
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    • pp.331-339
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    • 2003
  • 본 논문에서는 혼잡윈도우(CWnd) 와 RTT 파라메터를 사용해 흐름을 제어하는 개선된 TCP 혼잡제어 알고리즘을 제안한다. 제안된 알고리즘에서 혼잡윈도우를 TCP의 상태에 따라 저장된 RTT값으로 제어하여 혼잡상태를 회피한다. 또한 CWnd 값의 변동율을 줄이고 패킷 손실율을 낮춰서 네트워크 효율을 증대시킬수 있다. 시뮬레이션을 수행한 결과 제안된 알고리즘이 버퍼 이용율과 네트워크 효율면에서 기존 TCP 알고리즘보다 우수한 성능을 보였다.

A Novel Method for Avoiding Congestion in a Mobile Ad Hoc Network for Maintaining Service Quality in a Network

  • Alattas, Khalid A.
    • International Journal of Computer Science & Network Security
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    • 제21권9호
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    • pp.132-140
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    • 2021
  • Under the mobile ad-hoc network system, the main reason for causing congestion is because of the limited availability of resources. On the other hand, the standardised TCP based congestion controlling mechanism is unable to control and handle the major properties associated with the shared system of wireless channels. It creates an effect on the design associated with suitable protocols along with protocol stacks through the process of determining the mechanisms of congestion on a complete basis. Moreover, when bringing a comparison with standard TCP systems the major environment associated with mobile ad hoc network is regraded to be more problematic on a complete basis. On the other hand, an agent-based mobile technique for congestion is designed and developed for the part of avoiding any mode of congestion under the ad-hoc network systems.

Efficient Congestion Control for Interworking between 5G-System and LTE

  • Kim, Seog-Gyu
    • 한국컴퓨터정보학회논문지
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    • 제24권2호
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    • pp.49-56
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    • 2019
  • In this paper, we propose an efficient congestion control scheme for interworking between 5GS(5G system) and LTE(Long-Term Evolution), called ECC(Efficient Congestion Control). The proposed congestion control scheme (ECC) is considered for coexistence of 5GS and legacy LTE systems and provides a prompt service connectivity based on overriding method while the backoff timer is running in the UE. Also, we briefly introduce Rel-15 5GS from a congestion control perspective and the proposed ECC and simulation results for the existing legacy congestion control mechanism and ECC in the 5GS-LTE coexisting environment are presented. Lastly, the improvement direction is considered in future 3GPP 5GS phase 2 standard in this paper.

General AIMD with Congestion Window Upper Bound

  • Bui, Dang-Quang;Choi, Myeong-Gil;Hwang, Won-Joo
    • 한국멀티미디어학회논문지
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    • 제13권12호
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    • pp.1798-1804
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    • 2010
  • TCP with AIMD mechanism, one of the most popular protocols in internet, can solve congestion control in wired networks. This protocol, however, is not efficient in wireless networks. This paper proposes a new mechanism namely General AIMD with Congestion Window Upper Bound in which congestion window is limited by an upper bound. By applying optimization theory, we find an optimal policy for congestion window upper bound to maximize network throughput.

네트워크 혼잡효과를 고려한 인터넷망간 상호정산 방안 연구 (A Study on Settlements in Internet Interconnection under Internet Congestion)

  • 정충영
    • Journal of Information Technology Applications and Management
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    • 제14권2호
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    • pp.97-115
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    • 2007
  • The present paper investigates the technological and conceptional characteristics of peering and transit in internet interconnection. Especially, the market with two ISP competing for customers is modeled and the outcome with peering is compared with transit. This paper also analyze the congestion effects on retail price and network capacity. When there is congestion effects occurring from network sharing, the retail price is increased and the fixed fee is decreased with the degree of congestion. Finally, the optimal access charge assuring the socially optimal retail price and network capacity is derived.

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Network Congestion Control using Robust Optimization Design

  • Quang, Bui Dang;Shin, Sang-Mun;Hwang, Won-Joo
    • 한국통신학회논문지
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    • 제33권11B호
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    • pp.961-967
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    • 2008
  • Congestion control is one of major mechanisms to avoid dropped packets. Many researchers use optimization theories to find an efficient way to reduce congestion in networks, but they do not consider robustness that may lead to unstable network utilities. This paper proposes a new methodology in order to solve a congestion control problem for wired networks by using a robust design principle. In our particular numerical example, the proposed method provides robust solutions that guarantee high and stable network utilities.

사회비용을 반영한 최적택시거리.시간 병산요금구조 (Derivation of Optimum Time and Distance Taxi Fare Structure Based on Social Costs)

  • 원제무
    • 대한교통학회지
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    • 제3권1호
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    • pp.46-57
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    • 1985
  • The objective of this paper is to derive a optimum distance and time taxi fare structure based on social costs. Social costs expressed in terms of congestion and vehicle operating costs were successfully internalized. Speed and volume data for three major arterials in Seoul CBD were used. Optimum congestion charge turned out to be 97.01 Won/Km which can be regarded as congestion tax in the context of Seoul CBD. This congestion tax can possibly be incorporated into time-based taxi fare structure. Congestion is likely to be reduced as a result of imposition of time-based taxi fare which reflects social costs.

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An Efficient and Stable Congestion Control Scheme with Neighbor Feedback for Cluster Wireless Sensor Networks

  • Hu, Xi;Guo, Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권9호
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    • pp.4342-4366
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    • 2016
  • Congestion control in Cluster Wireless Sensor Networks (CWSNs) has drawn widespread attention and research interests. The increasing number of nodes and scale of networks cause more complex congestion control and management. Active Queue Management (AQM) is one of the major congestion control approaches in CWSNs, and Random Early Detection (RED) algorithm is commonly used to achieve high utilization in AQM. However, traditional RED algorithm depends exclusively on source-side control, which is insufficient to maintain efficiency and state stability. Specifically, when congestion occurs, deficiency of feedback will hinder the instability of the system. In this paper, we adopt the Additive-Increase Multiplicative-Decrease (AIMD) adjustment scheme and propose an improved RED algorithm by using neighbor feedback and scheduling scheme. The congestion control model is presented, which is a linear system with a non-linear feedback, and modeled by Lur'e type system. In the context of delayed Lur'e dynamical network, we adopt the concept of cluster synchronization and show that the congestion controlled system is able to achieve cluster synchronization. Sufficient conditions are derived by applying Lyapunov-Krasovskii functionals. Numerical examples are investigated to validate the effectiveness of the congestion control algorithm and the stability of the network.

송전 혼잡처리방법 변경이 시장 참여자 수익에 미치는 영향 분석 (Analysis of the Economic Impact of the Change in Congestion Management in the Korean Electricity Market)

  • 주성관;김지희;문국현
    • 조명전기설비학회논문지
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    • 제22권6호
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    • pp.134-140
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    • 2008
  • 국내 전력시장에서 현 혼잡처리방법은 혼잡비용(congestion cost)을 부가비용(uplift)형태로 전력 사용량에 비례하여 시장 전체의 모든 소비자가 부담하고 있다. 반면 다수의 해외 전력시장에서 채택하고 있는 지역한계가격 (Locational Margnal Pricing)방식은 혼잡으로 인한 비용을 시장 참여자들에게 차등적으로 배분하고 있다. 현재 국내 전력시장에서는 송전 혼잡처리방법의 변경으로 인한 시장참여자 수익에 미치는 영향에 대한 체계적인 연구가 미흡한 실정이다. 본 논문에서는 혼잡처리방법의 변경이 국내 전력시장의 소비자 비용과 발전기 잉여에 미치는 영향에 대해서 분석한다.

비연결형 데이터 서비스에서 LAN연동을 위한 폭주 제어에 관한 연구 (A study on congesting control scheme for LAN interworkding in connectionless data service)

  • 박천관;전병천;김영선
    • 전자공학회논문지S
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    • 제35S권3호
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    • pp.29-38
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    • 1998
  • This ppaer suggests a congestion control scheme for CL(ConnectionLess) overlay network using the feedback loops getween CL werver, between CL servers, and the header translation table of CL server. The CL overlay network for CBDS(Connectionless Broadband Data Service) defined by ITU0T(International Telecommunication Union-Telecommunication) consists of CL servers which route frames and links which connect between CL user and CL server or between CL servers. In this CL overlay network, two kinds of congestions, link congestion and CL server congestion, may occur. We suggest a scheme that can solve the congestion using ABR(Available Bit Rate) feedback control loop, the traffic control mechanism. This scheme is the link-by-link method suing the ABR feedback control loops between CL user and CL server or between CL servers, and the header translation table of CL server. As CL servers are always endpoints of ABR connections, the congestion staturs of the CL server can be informed to the traffic sources using RM(Resource Management) cell of the ABR feedback loops. Also CL server knows the trafffic sources making congestion by inspecting the source address field of CLNAP-PDUs(ConnectionLess Network Access Protocol - Protocol Data Units). Therefore this scheme can be implemeted easily using only both ABR feedback control loop of ATM layer and the congestion state table using the header translation table of CL server because it does not require separate feedback links for congestion control of CL servers.

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