波分复用（WDM）技术是目前发展很快的光传输技术之一。本文研究分析了单向波长通道保护环、双向波长通道保护环、两纤光复用段双向保护环这三种WDM环网保护机制，并对三种环网保护机制进行了比较全面的性能比较，所得出的结论对网络工作者根据不同的网络环境选择正确有效的保护机制起到了一定的理论指导作用。

WDM is one of the rapidly developed technologies in optical transmission．This paper analyses three protection mechanisms of WDM ring network，including the unidirectional wavelength channel protection， bidirectional wavelength channel protection，and the two-fiber optical multiplexing section bidirectional protection．This paper also presents a comprehensive comparison about the three protection mechanisms of WDM ring network．The conclusions may provides some theoretical guide on choosing the correct and effective protection mechanisms with different network environment．