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1.
As broadband access is evolving from digital subscriber lines to optical access networks, Ethernet passive optical networks (EPONs) are considered a promising solution for next generation broadband access. The point‐to‐multipoint topology of EPONs requires a time‐division multiple access MAC protocol for upstream transmission. In this paper, we propose a new enhanced dynamic bandwidth allocation algorithm with fairness called EFDBA for multiple services over EPONs. The proposed algorithm is composed of a fairness counter controller and a fairness system buffer in the optical line terminal. The EFDBA algorithm with fairness can provide increased capability and efficient resource allocation in an EPON system. In the proposed EFDBA algorithm, the optical line termination allocates bandwidth to the optical network units in proportion to the fairness weighting counter number associated with their class and queue length. The proposed algorithm provides efficient resource utilization by reducing the unused remaining bandwidth made by idle state optical network units.  相似文献   

2.
首先讨论了RPR网络中的公平性原则,然后结合该原则引入了一种适合于RPR网络的公平分配方案,基于该方案提出了一种能满足RPR环网性能要求的公平分配算法。该算法通过采用控制的方法为共享某链路的各数据流合理地分配带宽资源,从而达到:(1)各流的速率达到稳定;(2)链路缓存的占有量稳定到一个目标值;(3)链路带宽得到充分利用且实现公平分配。同时该算法能顺次协同地处理完网络中的各个链路,从而能够实现整个RPR环网的公平性与高的链路带宽利用率,达到RPR协议所要求的目标。给出了该算法的代码描述并对其作出稳定性分析,然后通过仿真对其性能进行了验证。  相似文献   

3.
区分服务网络中自适应加权调度方案的研究   总被引:1,自引:0,他引:1  
针对现有区分服务网络中多服务间带宽公平性问题,提出了一种自适应加权调度方案。该方案通过对本地节点缓存区指标的定期测量,计算得到在各队列间公平分配剩余带宽的调度权值。仿真结果表明,该方案可以在网络负载变化时自适应的快速调整到理想调度值,有效改进了带宽分配的公平性。  相似文献   

4.
针对区分服务保证转发服务中传输流间带宽分配公平性的问题,本文提出一种自适应RIO(ARIO,adaptive RIO)算法。仿真结果表明,ARIO算法不但可以在不同订购条件下获得更高的带宽利用率和更低的分组丢失率,而且有效地改进了原RIO算法的剩余带宽公平性问题。  相似文献   

5.
考虑光学开放接入网(optical open access network)中的公平性,将最大最小公平算法用到双向服务等级协议(D-SLA)中,提出了一种基于以太无源光学网络(EPON)的易于实现的双向服务等级协议公平带宽分配算法。算法使用了两轮分配,通过分级管理确定首要SLA和次要SLA,对业务提供商和用户进行分级区...  相似文献   

6.
为了实现吉比特无源光网络带宽分配的公平性,降低网络的传输延时,设计了一种新的媒质访问控制协议,提出了一种新的动态带宽分配算法。其基本思想是:在保证拥有不同QoS业务的用户得到认购速率的基础上,根据网络负载的大小,动态地将某些用户未使用的带宽分配给其他带宽需求大的用户,以提高网络的带宽利用率。仿真结果表明,这种新的算法在严格控制数据传输延时的前提下,能够保证多用户之间带宽分配的公平性。  相似文献   

7.
为了实现吉比特无源光网络带宽分配的公平性,降低网络的传输延时,设计了一种新的媒质访问控制协议,提出了一种新的动态带宽分配算法.其基本思想是:在保证拥有不同QoS业务的用户得到认购速率的基础上,根据网络负载的大小,动态地将某些用户未使用的带宽分配给其他带宽需求大的用户,以提高网络的带宽利用率.仿真结果表明,这种新的算法在严格控制数据传输延时的前提下,能够保证多用户之间带宽分配的公平性.  相似文献   

8.
一种用于IEEE 802.16无线城域网TDD模式中的带宽调度方案   总被引:6,自引:0,他引:6  
该文提出了一种用于IEEE 802.16宽带无线接入系统TDD模式下的公平而有效的带宽分配调度体系。与该领域中传统的固定带宽分配方式相比,该文提出的调度体系结构综合考虑了上下行链路不同业务带宽需求并进行动态带宽分配。该文提出一种新的亏空公平优先级队列(DFPQ)算法来调度不同优先级的业务流,可以为系统提供更好的公平性。仿真结果显示该文提出的调度体系结构能够很好地满足所有类型业务的服务质量(QoS)需求,并提供较好的公平性。  相似文献   

9.
The traffic load of wireless LANs is often unevenly distributed among the access points (APs), which results in unfair bandwidth allocation among users. We argue that the load imbalance and consequent unfair bandwidth allocation can be greatly reduced by intelligent association control. In this paper, we present an efficient solution to determine the user-AP associations for max-min fair bandwidth allocation. We show the strong correlation between fairness and load balancing, which enables us to use load balancing techniques for obtaining optimal max-min fair bandwidth allocation. As this problem is NP-hard, we devise algorithms that achieve constant-factor approximation. In our algorithms, we first compute a fractional association solution, in which users can be associated with multiple APs simultaneously. This solution guarantees the fairest bandwidth allocation in terms of max-min fairness. Then, by utilizing a rounding method, we obtain the integral solution from the fractional solution. We also consider time fairness and present a polynomial-time algorithm for optimal integral solution. We further extend our schemes for the on-line case where users may join and leave dynamically. Our simulations demonstrate that the proposed algorithms achieve close to optimal load balancing (i.e., max-min fairness) and they outperform commonly used heuristics.  相似文献   

10.
该文针对以OFDMA(Orthogonal Frequency Division Multiple Access)为多址接入方式的多无线电系统中用户比例公平性和系统效率问题进行了研究,提出一种联合资源分配算法,不仅保证了用户比例公平性下系统的吞吐量,还充分考虑了分配的带宽是子信道带宽整倍数的特点,对分配给每个终端的带宽进行子信道整数倍调整。最后通过仿真对比,从系统吞吐量和公平性两方面给出了算法的性能。  相似文献   

11.
为了实现吉比特无源光网络(GPON)带宽分配的公平性,降低网络的丢包率及传输延时,文章研究了GPON系统传输汇聚层的帧结构及动态带宽分配的实现方法,提出了一种新的动态带宽分配(DBA)算法--基于QoS的二层动态带宽分配算法.基本思路是根据不同等级业务的带宽需求,在PON层和ONU层分别进行带宽的合理分配.理论分析和仿真试验证明,这种算法可以提高带宽的利用率,保证不同业务的不同时延要求,并且对不同用户和不同等级的业务都具有很好的公平性.  相似文献   

12.
Cooperative access among user devices by sharing wireless access bandwidth opens a new paradigm in heterogeneous networks.However,how to stimulate cooperative relay nodes forwarding service data for others and allocating corresponding bandwidth to support it are two key issues in the cooperative access.This paper proposes a Stackelberg game based framework which is benefit participants including relay nodes and client nodes.This framework generalizes the pricing based bandwidth allocation algorithm by the Stackelberg game model,which optimizes the profit of the cooperative relay nodes while guaranteeing the bandwidth requirements of client nodes.We transform the profit maximization problem into a convex problem and solve it using the convex optimization method.The simulation results demonstrate that the proposed framework and corresponding algorithms outperform the bidding weight proportional fairness and fixed value bandwidth allocation ones significantly.  相似文献   

13.
李昭  陈前斌 《通信技术》2008,41(5):72-74
以太无源光网络综合了PON技术和以太网技术的优点,以其高带宽、低成本、易使用.易升级的优良特性成为目前光接入网的优选方案.文中在IPACT算法的基础上提出了一种支持队列优先级的上行接入带宽分配算法,并构建了基于OPNET的系统仿真模型,评价了在信源到达为Pareto分布下该算法的性能.仿真表明该算法满足业务的QoS,提高了带宽的吞吐率,并保证了各业务队列带宽分配的公平性.  相似文献   

14.
一种EPON-WiMAX融合网络带宽分配算法   总被引:1,自引:0,他引:1  
文中提出了一种应用于EPON和WiMAX的融合网络,实现用户多优先级业务区分并保证用户QoS的动态带宽分配算法。算法让EPON网络和WiMAX网络协同分配带宽,在EPON网络带宽分配的过程中加入WiMAX网络的带宽分配。整体算法使得因得不到足够带宽而受到影响的用户数保持在最小,同时加入令牌机制兼顾了用户之间的公平性。文中在现有融合网络框架的基础上提出算法,并给出了算法的具体设计步骤,详细分析了带宽申请和分配的过程,讨论了算法的优越性。  相似文献   

15.
In the metro-access optical network, a two-stage bandwidth-allocated algorithm is proposed for the multi-subsystem-based virtual passive optical network (VPON) that can achieve the syncretism of multiple systems such as time division multiplexing-PON, wavelength division multiplexing-PON and orthogonal frequency division multiplexing-PON. In this paper, the bandwidth is allocated in two stages. The first-stage allocation is designed to improve the admission probability of new VPONs by allocating bandwidth to all new VPONs followed by original VPONs. Meanwhile, to avoid the bandwidth being monopolized by the new VPONs, the bandwidth allocated to each VPON is no more than its guaranteed bandwidth. Therefore, the whole fairness can be guaranteed. The second-stage allocation is used to promote the bandwidth-utilized ratio by assigning the remaining bandwidth to VPONs whose demand is not fully met in the first stage. With the two-stage allocation, not only the admission probability can be improved, but also the bandwidth-utilized ratio can be promoted. MATLAB is used to evaluate the performance of proposed algorithm according to admission probability of new VPONs and bandwidth-utilized ratio.  相似文献   

16.
GPON系统中基于QoS的动态带宽分配算法的研究   总被引:2,自引:1,他引:1  
为了实现吉比特无源光网络(GPON)带宽分配的公平性,降低网络的丢包率及传输延时,研究了GPON系统传输汇聚层的帧结构及带宽分配的实现方法,提出了一种新的动态带宽分配(DBA)算法--基于QoS的二层动态带宽分配算法.性能分析与对比表明,这种算法对不同用户和不同等级的业务都具有很好的公平性,并可以降低低等级业务的传输延时.  相似文献   

17.
Factors such as link differences and TCP friendliness constraints lead to the problem of unfair bandwidth allocation when the TCP congestion control mechanism was applied directly to multi-path transmission.To address the problem,it was proposed that a multipath congestion control algorithm was based on link capacity.The proposed algorithm which was based on the concept of feedback regulation achieved multipath joint congestion control by establishing the M/M/1 cache queue model to adjust the throughput rate of senders.Experimental results show the proposed algorithm can improve the multipath transmission bandwidth utilization and the multipath congestion control algorithm responsiveness,and ensure the fairness of multipath transmission.  相似文献   

18.
Ethernet passive optical network (EPON) becomes a key technology for the next generation broadband access networks due to its cost-effectiveness and high data rate. One of the research issues in EPON is to support service differentiation and fairness. For service differentiation, the conventional limited algorithm is extended with strict priority queuing (SPQ). However, due to ONU-bounded bandwidth allocation, those extensions from the limited algorithm have difficulties in supporting QoS and fairness when the uplink is instantaneously overloaded. To overcome the disadvantages of ONU-bounded bandwidth allocation, instead of allocating the bandwidth on per ONU basis, the proposed class-limited algorithm allocates the bandwidth on per service class basis. Our simulations show that the class-limited algorithm is more efficient to differentiate services and to fairly share residual bandwidth than other limited schemes combined with SPQ, particularly for instantaneous overload condition.  相似文献   

19.
Fair bandwidth sharing is important for the Internet architecture to be more accommodative of the heterogeneity. The Internet relies primarily on the end-systems to cooperatively deploy congestion control mechanisms for achieving high network utilization and some degree of fairness among flows. However, the cooperative behavior may be abandoned by some end-systems that act selfishly to be more competitive through bandwidth abuse. The result can be severe unfairness and even congestion collapse. Fairness-driven active queue management, thus, becomes essential for allocating the shared bottleneck bandwidth fairly among competing flows. This paper proposes a novel stateless active queue management algorithm, termed CHOKeH, to enforce fairness in bottleneck routers. CHOKeH splits the queue into dynamic regions at each packet arrival and treats each region differently for performing matched-drops using a dynamically updated drawing factor, which is based on the level of queue occupancy and the buffer size. In this way, CHOKeH can effectively identify and restrict unfair flows from dominating the bandwidth by discarding more packets from these flows. The performance of CHOKeH is studied through extensive simulations. The results demonstrate that CHOKeH is well suited for fair bandwidth allocation even in the presence of multiple unresponsive flows and across a wider range of buffer sizes. The results also show the ability of CHOKeH to provide inter-protocol and intra-protocols fairness and protection for short-lived flows. With a low per-packet-processing complexity, CHOKeH is amenable to implementation in core routers to offer an effective incentive structure for end-systems to self-impose some form of congestion control.  相似文献   

20.
夏明  黄勤珍 《通信技术》2009,42(1):180-182
在分析研究弹性分组环(RPR)带宽分配的基础上,提出一种新的快速消除拥塞的公平算法(RFCA)。该算法由拥塞链路所在的节点不断计算影响该链路的节点个数及公平带宽分配,并将分析结果告知上游节点。上游节点再次分析计算,直到找出造成拥塞的节点。理论分析及仿真结果表明,RFCA优于现有IEEE802.17采用的AM算法,在保证节点业务发送公平性的同时,消除了AM算法的振荡现象,提高了链路的利用率,并且不影响业务流的空间复用性。  相似文献   

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