基于带宽借贷的EPON动态带宽分配算法  

Dynamic bandwidth allocation algorithm based on bandwidth debit and credit for EPON

作　　者：刘海[1] 谭喆元[1] 刘德明[1] 黄德修[1] 

机构地区：[1]华中科技大学光电子科学与工程学院,武汉430074

出　　处：《高技术通讯》2008年第11期1101-1105,共5页Chinese High Technology Letters

基　　金：863计划(2001AA122023)

摘　　要：针对以往以太网无源光网络(EPON)动态带宽算法中存在的带宽分配不公平性问题,提出了基于带宽借贷机制的动态带宽算法 LLR 和 LWR,其基本思想为当某光网络单元(ONU)有空余带宽时,光线路终端(OLT)将此 ONU 多余带宽借贷给重负载 ONU,当债权 ONU 遇到带宽不足的情况时,OLT 将会安排负债 ONU 偿还其未满足请求部分带宽。通过在正常使用和存在'贪婪'用户的两种情况下的仿真,分析了这两种算法的平均时延和丢包率特性。仿真结果表明这两种算法能为正常使用用户提供有保障的公平性服务,消除了以往算法在若干用户过量使用的情况下所有用户都受影响的问题,使动态带宽分配更加公平。Two novel dynamic bandwidth allocation （DBA） algorithms （LLR and LWR） based on bandwidth debit and credit were proposed to solve the problem of unfair bandwidth allocation in Ethernet passive optical networks （EPON）. Their main idea is that the optical line terminal （OLT） can debit and credit the excessive bandwidth from those lightly loaded optical network units （ONUs） to highly loaded ONUs, and when in burst of traffic data the bandwidth of those credit ONUs can be reimbursed from those debit ONUs. The simulation results showed that these algorithms performed well in successful assurance of the brought bandwidth of ONUs in normal utilization, rather than penalties executed on all ONUs in former algorithms when there were some greedy ONUs.

关 键 词：以太网无源光网络 动态带宽分配 带宽借贷 公平性保障 

分 类 号：TN929.1[电子电信—通信与信息系统]