同义词
1)bidirectional linear switched ring,双向线性倒换环2)two-fiber bidirectional linear switched ring,双纤双向线性倒换环3)bidirectional multiplex section switching ring,双向复用段倒换环4)4-fiber-cable both-direc-tion-reuse reversible ring,4纤双向复用段倒换环5)bidirectional protection switching,双向保护倒换6)UPSR,单向通道倒换环
