中文摘要：

基于铁路时间同步网的现状，研究了OTN超长距离传递1588v2时间信号；基于链路的时延和主从时钟的时差，对时间传递的精度进行了测量，包括对OTN时间传递精度和OLP、PTP倒换时间的测试研究，获得了较高精度的测试数据。

英文摘要：

Based on the current situation of railway time synchronization network, this paper studies the 1588v2 time signal of OTN long distance transmission. Based on the delay of the link and the time difference of the master and slave clock, the paper measures the accuracy of the time transfer, including the OTN time transfer accuracy and the OLP, PTP switching time, obtains the high precision test data.