• Title/Summary/Keyword: Engineering Fair

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Hierarchical Fair Queueing: A Credit-based Approach for Hierarchical Link Sharing

  • Jun, Andrew Do-Sung;Choe, Jin-Woo;Leon-Garcia, Alberto
    • Journal of Communications and Networks
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    • v.4 no.3
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    • pp.209-220
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    • 2002
  • In this paper, we propose a hierarchical packet scheduling technique to closely approximate a hierarchical extension of the generalized processor sharing model, Hierarchical Generalized Processor Sharing (H-GPS). Our approach is to undertake the tasks of service guarantee and hierarchical link sharing in an independent manner so that each task best serves its own objective. The H-GPS model is decomposed into two separate service components: the guaranteed service component to consistently provide performance guarantees over the entire system, and the excess service component to fairly distribute spare bandwidth according to the hierarchical scheduling rule. For tight and harmonized integration of the two service components into a single packet scheduling algorithm, we introduce two novel concepts of distributed virtual time and service credit, and develop a packet version of H-GPS called Hierarchical Fair Queueing (HFQ). We demonstrate the layerindependent performance of the HFQ algorithm through simulation results.

A NOTE ON FELLER`S THEOREM

  • Hong, dug-Hun
    • Communications of the Korean Mathematical Society
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    • v.14 no.2
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    • pp.425-428
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    • 1999
  • In this note we have generalization of Feller`s theorem to real separable Banach spaces, from which we obtain easily Chow-Robbins “fair" games problem in the Banach spaces.aces.

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A Study on Fair Bandwidth Allocation in Core-Stateless Networks: Improved Algorithm and Its Evaluation

  • Kim, Mun-Kyung;Seo, Kyoung-Hyun;Yuk, Dong-Cheol;Park, Seung-Seob
    • Journal of Navigation and Port Research
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    • v.28 no.4
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    • pp.299-303
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    • 2004
  • In the Internet, to guarantee transmission rate and delay and to achieve fair bandwidth allocation, many per-flow scheduling algorithms, such as fair queueing, which have many desirable properties for congestion control, have been proposed and designed. However, algorithms based on per-flow need maintain rate state, buffer management and packet scheduling, so that it cost great deal : implement. Therefore, in this paper, to implement routers cost-effectively, we propose CS-FNE algorithm based on FNE in Core-Stateless network We evaluate CS-FNE comparing with four additional algorithms i.e., CSFQ, FRED, RED and DRR, in several different, configurations and traffic sources. Through simulation results, we show that CS-FNE algorithm can allocate fair bandwidth approximately and is simpler and easier to implement than other per-flow basis queueing mechanisms.

Packet Fair Scheduling in Wireless Networks (무선 네트워크 환경에서의 공정한 패킷 스케줄링)

  • Park, Young-Il;Ha, Rhan
    • Proceedings of the Korean Information Science Society Conference
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    • 2000.10c
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    • pp.473-475
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    • 2000
  • 무선 네트워크의 급격한 성장으로 기존의 전자우편, 멀티미디어 등의 응용을 이동 컴퓨팅 환경에서 보다 효과적으로 지원해야 할 필요성이 증대되었다. 기존 유선 네트워크 환경에서 사용자의 독립적 서비스 보장과 요구 비율에 따른 자원의 공정한 배분을 위해서 Fair Queueing 기법이 제안되었다. 이 Fair Queueing 기법을 무선 네트워크에 적용하려는 연구가 진행되고 있으나 무선 미디어 자원의 빈약성과 사용자 이동에 따른 오류 발생 가능성 등으로 인해 아직까지 체계적인 기술은 미비한 형편이다. 본 논문에서는 기존 Fair Queueing 기법에서 각 세션의 가중치를 조절하여 무선 네트워크 환경에서 사용자의 다양한 서비스 품질(QoS; Queueing of Service)을 지원하고 오류 발생시 급격한 서비스 품질 저하를 방지하는 패킷 서비스 기법을 제시하고 그 성능을 분석한다.

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Towards Fair and Secure e-Commerce Model In P2P Network

  • Jung Ji Won;Sur Chul;Rhee Kyung Hyune
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.47-51
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    • 2004
  • In this paper we propose a fair and secure e-commerce model for P2P network, in which communication entities can buy and sell products by P2P contract. In particular, we focus on a fair transaction protocol that is based on a collaboration with distributed communication entities. This feature makes our model very attractive in P2P networking environment which does not depend on any central trusted authority for managing communication entities.

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A Study on the Propulsion Shaft Alignment Calculation by the Matrix Method of Three-Moment Theory (삼연모먼트정리의 매트릭스산법에 의한 박용추진축계 배치계산에 관한 연구)

  • 문덕홍;전효중
    • Journal of Advanced Marine Engineering and Technology
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    • v.5 no.1
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    • pp.20-27
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    • 1981
  • The alignment of propulsion shaft systems by the fair curve method has been developed over the past twenty years and in recent years its basic problems have been almost solved. At the present time, studies on introducing actual conditions are being undertaken. In a fair curve alignment, its aim is to achieve a stable shaft system which will be relatively insensitive to misalignment or the influence of external factors such as thermal variations due to the sunshine, speed change, etc. The key point of fair curve alignment is the calculations of reactions in the straight support and reaction influence numbers. The present authors have developed those calculating method by the matrix method of the three-moment theorem. The fair curve alignment is based on the analysis of propulsion shaft system which is assumed as a continous beam on multiple support points. The propeller shaft is divided into several elements. For each element, the nodal point equation is derived by the three-moment theorem. Reaction of supporting points of straight shaft and reaction influence numbers are calculated by the matrix calculation of each nodal point equation. It has been found that results of calculation for the model shaft agree well with those of experiment which had been measured by the strain gauge method. Results of calculation for the actual propulsion shafting of the steam turbine had been compared also with those of Det norske Vertas.

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Providing Guaranteed Delay in Multimedia Ad Hoc Wireless Networks (멀티미디어 Ad Hoc 무선망에서의 지연시간 보장방안)

  • Yang, Hyun-ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.6
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    • pp.1177-1186
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    • 2003
  • The multimedia ad hoc wireless network is quite an attractive issue since it offers a flexible solution to enable delivery of multimedia services to mobile end users without fixed backbone networks. However, with the unique design challenges of ad hoc wireless networks, it is a non-trivial issue to provide bounded delay guarantee, with fair share of resources. In this paper, we implemented the delay guaranteed fair queueing (DGFQ) scheme distributively. Through the results of performance evaluation, we can conclude that DGFQ also performs well to control bounded delay in multimedia ad hoc wireless networks.

Fairness CSMA/CA MAC Protocol for VLC Networks

  • Huynh, Vu Van;Jang, Yeong-Min
    • International journal of advanced smart convergence
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    • v.1 no.1
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    • pp.14-18
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    • 2012
  • This paper presents a fair MAC protocol based on the CSMA/CA algorithm in visible light communication (VLC) networks. The problem of bandwidth sharing among differentiated priority in VLC networks can be solved by using number of backoff time and backoff exponent parameters with AIFS. The proposed algorithm can achieve fair allocation of the bandwidth resource among differentiated priority. The two dimension Markov chain is assisted for analyzing the proposed mechanism about throughput and delay metrics. Numerical results show that our proposed algorithm improves the fairness among different traffic flows.

Fair TCP Window-based Control in Single Congested Network with Explicit Congestion Notification (TCP 단일 혼잡 망에서의 ECN을 이용한 공정한 윈도우 제어)

  • Byun, Hee-Jung;Lim, Jong-Tae
    • Proceedings of the KIEE Conference
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    • 2002.11c
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    • pp.27-30
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    • 2002
  • In this paper, we propose a window-based congestion control algorithm to achieve a fair sharing of the available bandwidth in ECN capable heterogeneous TCP networks with a single bottleneck link. The proposed algorithm is based on extracting the network status from the successive binary congestion information provided by ECN. From the explicit network information, we estimate the fair window size proportional to the propagation delay. Through simulations, the effect and performance of the proposed algorithm are shown for the heterogeneous networks.

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