地區維護站 設施及設備維護站 訊框 國際傳輸維運支援系統 監視控制系統 中介設備 人機介面語言 光終端機 調度及管理系統 非同步數位階層 同步數位階層 傳輸次網路維運控制系統 Area maintenance station AMS Facility and equipment maintenance station FEMS Frame relay FR International transmission operation support system ITOSS Monitor and control MAC Mediation device MD Man machine language MML Optical line terminating equipment OLTE Provisioning and management system PAMS Plesiochronous digital hierarchy PDH Synchronous digital hierarchy SDH Transmission subnetwork controller system TSNC