目前已经实现的无源光网络(PON)保护方案通常保护的是光线路终端(OLT)的PON媒体接入控制器(MAC)到光网络单元(ONU)的PON MAC之间的光路，无法对OLT整体设备进行保护。文章介绍了一种跨OLT的PON保护方案：ONU 同时在两台OLT上注册，两台OLT之间通过传输控制协议(TCP)方式使配置和状态等信息周期性地同步。该方案可以实现对OLT设备的整体保护。

The existing PON protection scheme covers only the optical path between the PON MAC of OLT and the PON MAC of ONU, but not the entire OLT equipment. This paper introduces a new protection solution, which covers the whole OLT equipment. In this new solution, ONU is registered with two OLT equipments at the same time and such information as configuration and status are periodically synchronized between the two OLT’s by means of TCP communication.