共查询到18条相似文献,搜索用时 156 毫秒
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通过阐述以太网无源光网络(EPON)系统信道传输数据方式以及动态带宽分配的工作原理,进一步研究了动态带宽分配算法(DBA)在EPON系统中的应用。提出一种基于服务质量(QoS)的EPON系统动态带宽分配机制,该机制根据不同业务的优先级和动态带宽分配算法,灵活地分配上行带宽,提高了带宽利用率,改善了服务质量。 相似文献
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为了合理分配EPON上行信道带宽,提出一种能够区分服务等级的固定周期轮询动态带宽分配算法。该算法将光网络单元(ONU)的业务分为三个等级,根据不同的业务等级动态分配上行带宽,有效保证整个EPON网络的QoS以及带宽分配的公平性。同时,为了进一步提高EPON系统上行链路的带宽利用率,克服算法产生的idle time问题,对算法进行了改进。最后,对该算法进行仿真实验。 相似文献
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动态带宽分配是以太网无源光网络(EPON)系统中的一个重要研究领域,提出了一种基于业务的两层三次带宽分配的DBA新型算法.该算法在兼顾动态带宽分配的带宽利用率和QOS保证方面进行了改进,通过研究分析给出了最优算法,并在模拟流量下进行了性能分析.通过与已有算法的对比,证明其有很好的性能. 相似文献
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对现有的EPON上行链路动态带宽分配算法进行了改进,有效地提高了带宽利用率和时延抖动两个指标.同时利用OPNET构建了EPON系统仿真模型,仿真结果表明:改进后的算法具有较高的带宽利用率和较低EF业务时延抖动.为制定多业务QoS的EPON上行接入带宽分配标准提供参考. 相似文献
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一种公平的EPON动态带宽分配算法 总被引:7,自引:0,他引:7
提出一种EPON上行链路动态带宽分配算法一周期比例DBA。ONU基于多门限周期地上报带宽请求,OLT根据ONU的带宽请求及其合约带宽进行动态带宽分配。当多个ONU竞争系统带宽时,OLT按照ONU合约带宽的比例进行带宽分配。仿真结果表明:周期比例DBA算法在实现高带宽利用率的同时又具有良好的公平性。 相似文献
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CHEN Xue~ ZHANG Yang~ HUANG Xiang~ DENG Yu~ SUN Shu-he~ .Telecommunication Engineering School Beijing University of Posts Telecommunications Beijing P.R. China .GW Technologies Co. Ltd Beijing P.R. China 《中国邮电高校学报(英文版)》2005,12(2)
1IntroductionIt seems that providing broadband services is thesaver of telecom industry. Long-haul and Metro corenetworks are capable of carrying broadband servicessince they have experienced a dramatic i mprovement inbandwidth capacity and efficiency with the advent oftechnologies such as Dense Wave length Division Multi-plexing (DWDM)[1 ~3]and other newtechnologies .Buta clear bottleneckexistsinthe“first mile”of access net-work[4]. Without eli minationthe bandwidth bottlenecksthat exis… 相似文献
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一种支持多用户SLA的EPON上行带宽分配算法设计 总被引:6,自引:0,他引:6
在接入网服务等级协定的基础上,分析了以IPACT和CyclicDBA为代表的EPON上行动态带宽分配算法,讨论了其对EPON上多用户SLA支持所存在的固有缺陷。提出了适合SLA应用的EPON控制帧结构:授权帧和请求帧。根据这两种控制帧,设计了一种新型的支持多用户SLA的EPON上行信道带宽分配算法,等级轮询固定周期算法。通过理论分析和计算机仿真测试表明该算法针对EPON不同类型的接入用户均达到了较理想的性能指标,高优先级业务良好的时延和时延抖动特性,各种业务队列的尺度平稳,同时HPFCT还解决了传统轮询算法中低负载时下行带宽浪费明显的问题。 相似文献
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The passive optical network (PON) technology has been drastically improved in recent years. In spite of using the optical technology, the utilization of the entire bandwidth is a very challenging task. The main categories of PON are the Ethernet passive optical network (EPON) and gigabit passive optical network (GPON). These two networks use the dynamic bandwidth allocation (DBA) algorithm to attain the maximum usage of bandwidth, which is provided in the network dynamically according to the need of the customers with the support of the service level agreement (SLA). This paper will provide a clear review about the DBA algorithm of both technologies as well as the comparison. 相似文献
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Nurul Asyikin Mohd Radzi Norashidah Md. Din Mohammed Hayder Al-Mansoori Sajaa Kh. Sadon Mohd Shahmi Abdul Majid 《Photonic Network Communications》2014,27(1):1-7
Ethernet Passive Optical Network (EPON) has emerged as a promising technology since it offers high bandwidth at a distance that can go up to 20 km. In the upstream EPON transmission, a dynamic bandwidth allocation (DBA) algorithm is needed to avoid collisions and to efficiently allocate the bandwidth. This paper proposes an algorithm called as a Universal DBA (UDBA) algorithm that can support the priority universally in the entire EPON system. A peripheral interface controller (PIC)-based EPON testbed is used to test the algorithm within the mulipoint control protocol environment. For the performance study, we have compared the results achieved using UDBA in terms of delay, throughput, and fairness with two other DBA algorithms. UDBA shows improvements in terms of expedited forwarding, assured forwarding and best effort delay as much as 43.9, 42.6, 20 % over User-oriented Hierarchical Bandwidth Scheduling with Single Cycle (UHSA-S) and 37.5, 20.2, 25.3 % over Modified Smallest Available Report First (MSARF), respectively. Throughput is improved as high as 17.9 % over UHSA-S and 12.8 % over MSARF. In addition, the fairness index of UDBA is higher up to 14 % as compared to UHSA-S and 2.7 % as compared to MSARF. 相似文献
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《Selected Areas in Communications, IEEE Journal on》2005,23(8):1467-1478
Ethernet passive optical networks (EPONs) have emerged as the one of the most promising candidates for next-generation access networks. These new architectures couple low-cost optics with advanced edge electronics to offer vastly improved scalability over competing digital subscriber line and cable modem offerings. This paper proposes several novel architectural enhancements for EPON, which will help increase the viability of optical access over a broader range of subscriber access scenarios. Specifically, this paper proposes a two-stage EPON architecture that allows more end-users to share an optical line terminal link, and enables longer access reach/distances (beyond the usual 25 km distance). In addition, a new dynamic bandwidth allocation (DBA) algorithm is proposed to effectively allocate bandwidths between end users. This DBA algorithm can support differentiated services in a network with heterogeneous traffic. We conduct detailed simulation experiments to study the performance and validate the effectiveness of the proposed architecture and algorithms. 相似文献
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Ethernet Passive Optical Network (EPON) has been widely considered as a promising technology for implementing the FTTx solutions to the “last mile” bandwidth bottleneck problem. Bandwidth allocation is one of the critical issues in the design of EPON systems. In an EPON system, multiple optical network units (ONUs) share a common upstream channel for data transmission. To efficiently utilize the limited bandwidth of the upstream channel, an EPON system must dynamically allocate the upstream bandwidth among multiple ONUs based on the instantaneous bandwidth demands and quality of service requirements of end users. This paper introduces the fundamental concepts on EPONs, discusses the major issues related to bandwidth allocation in EPON systems, and presents a survey of the state-of-the-art dynamic bandwidth allocation (DBA) algorithms for EPONs. 相似文献