A.雙纖雙向傳輸 B.單纖雙向傳輸 C.單纖單向傳輸
A.2.048Lfbit/s B.8.448Mbit/s C.34.368Mbit/s D.139.264Mbit/s
A.再生段開銷 B.管理單元指針 C.復(fù)用段開銷 D.凈負(fù)荷