A.專線接入 B.ip host C.ip pool
A.并行信號(hào)與串行信號(hào) B.高壓信號(hào)與低壓信號(hào) C.交流信號(hào)與直流信號(hào) D.數(shù)字信號(hào)與模擬信號(hào)
A.QAM CAP DMT B.QOM CAP DMT C.QAM COP DMT