一种APON上行带宽分配方案

文中介绍了APOW（ATM无源光网络），在此基础上提出了APON上行带宽动态分配的一种方案--“最小分配”方案：即光线路终端（OLT）在分配上行带宽时，首先满足各光网络单元（ONU）的基本带宽需求，以保证电话等实时业务的传输；同时又以特定的算法使ONU中的上行发送缓冲队列最短。最后，使用仿真手段对本方案与“平均分配”方案进行了性能比较。“最小分配”方案的平均信元接入时延、ONU上发缓冲区尺寸、上行带宽使用效率和信元丢失率等性能指标均优于“平均分配”方案。

A scheme of upstream bandwidth allocation for A-PON

Based on the presentation of APON(Passive Optical Networks basedon ATM)，a scheme of upstream bandwidth dynamic allocation for APON is given，namely“minimum allocation”scheme：When an OLT allocates bandwidth，the prime bandwidth request of all ONUs is met at first，so that the transmission of basic services，such as POTS，is available；At the same time，a special mechanism is used to reduce the upstream queues to the lowest size at ONU.In the end，a comparison of performance between this scheme and the“share alike”scheme is implementation by a simulation experiment.Many performances，such as the mean cell access delay，the mean cell access delay of real-time service，the upstream buffers in ONU，the efficiency of upstream bandwidth，and the cell loss rate，for“minimum allocation”scheme are better than for“share alike”scheme.