By analyzing2Mbit/s slip code during the intercommunication of Fujitong and Lucent SDH transmission equipment on155Mbit/s line interface,this paper declares that the direct reason for the trouble is non adaptation of label bits in VC-12POH V5byte.

• 通过对日本富士通公司与上海朗讯公司SDH传输设备在155Mbit/s口互通时出现的2Mbit/s滑码故障分析判断,指出了VC-12POHV5字节中Label比特不适配是该故障的直接原因。