【作者】 李君；

【导师】 范红；

【作者基本信息】 南京邮电大学 ， 光学工程， 2011， 硕士

【摘要】 近年来,随着用户对带宽需求的进一步增长及接入用户数的不断增加,传统的EPON系统已经不能满足用户对带宽的需求。WDM-PON具备强大的接入能力,然而,在现阶段WDM-PON的成本太高,还不适合在成本敏感的接入网中大规模应用。一种折衷的方案即基于TDM/WDM的混合PON已经成为研究的热点,并有逐渐商用的趋势。多波长EPON系统就是这样一种由TDM向WDM过渡过程中的灵活方案。本文首先介绍了mλ-EPON系统的框架和工作原理,对MPCP的扩展协议——mλ-MPCP和注册机制进行了简单讨论,提出了mλ-EPON系统的测距方案并探讨了mλ-EPON系统的保护倒换功能。本文重点探讨了多波长EPON系统的上行资源带宽调度算法。经典的波长调度资源调度策略S-IPACT(DRA-1)由于采用即时授权方式,没有形成完善的波长和时隙(T+λ)统一调度策略,致使信道利用率低。针对这一问题,本文设计了具有QoS保证的固定轮询周期资源调度算法(DRA-2)和负载均衡的自适应周期资源调度算法(DRA-3)。在DRA-2的设计中考虑了2种保证带宽的计算方案和4种剩余带宽分配方案,并通过OPNET Modeler仿真验证了区分ONU类型确定保证带宽和分配剩余带宽的方案优于其它方案。DRA-3采用了带宽请求值最大的ONU(M)最后授权的方式,并在两个波长信道上各分配一定的带宽,使得总的授权均衡,最大程度的利用了带宽资源。同时,采用M提前REPORT机制也大大降低甚至清除了RTT。仿真结果表明,DRA-2算法中EF业务的延时稳定,业务在延时方面的QoS具有保障。DRA-3与其他DRA算法相比,具有最高信道利用率。更多还原

【Abstract】 In recent years, with users access to the further growth of the demand for bandwidth and num-ber of users continues to increase, the traditional EPON system is unable to meet the demand for bandwidth. WDM-PON have a strong ability to access, but, at the present stage WDM-PON the cost was too high, is not suitable for large-scale application of cost-sensitive access network. A compromise solution based on TDM/WDM mixed PON has become a hot spot of research, and gradually business trends. Multi-wavelength EPON system is such a flexible solutions in the process of transition from TDM to the WDM.This article first introduced mλ-EPON system framework and work principle and extend agreement on the MPCP--mλ-MPCP simple discussions and registration system, set mλ-EPON systems ranging scheme and explore mλ-EPON protection switching functions.This paper focus study on bandwidth of upstream resources scheduling algorithms in mλ-EPON system. Wavelength scheduling resource scheduling strategy of classic S-IPACT.DRA-1 with the use of authorization, did not form a perfect wavelength and time slot“T+λ”unified dis-patch strategy, causing the channel low utilization rate. In view of this problem, This paper de-signed with fixed polling period of resource scheduling algorithm of QoS guarantee DRA-2 and adaptive cycle of resource scheduling algorithm of load balancing DRA-3. DRA-2 calculation pro-gram design in consideration of the 2 guaranteed bandwidth and 4 remaining bandwidth allocation scheme and OPNET Modeler simulation of distinguishing ONU type determines the guaranteed bandwidth and distribution of residual scheme of bandwidth than other solutions. DRA-3 use of bandwidth request values the largest ONU(M) final authorization, and on two wavelength channel allocation of a certain amount of bandwidth, which authorized the total balance, the maximum uti-lization of bandwidth resources. meanwhile, M earlier REPORT mechanism has been greatly re-duced or even eliminated RTT. Simulation results show that EF business DRA-2 algorithm of delay stability, business QoS guarantee in delay. DRA-3 compared with other DRA algorithm, with the maximum channel utilization.更多还原