单项选择题
A.1850TSS-160 B.1850TSS-5 C.1850TSS-40 D.1850TSS-100
A.Transport Service Switch B.Transmit Service Switch C.Transport Switch Service D.Transmit Switch Service
A.发送的测试帧 B.接收的测试帧 C.收到的应答帧 D.发送的应答帧