日韩欧美亚洲 _ 欧美亚洲一区 _ 日本亚洲欧美 _ 亚洲精品欧美 国产白袜脚足J棉袜在线观看_亚洲熟妇av一区二区三区_久久天天躁狠狠躁夜_精品众筹模特私拍在线

單項(xiàng)選擇題

Which statements is true about Foreign Exchange Station (FXS) ports on a router?()

A.the FXS interface allows an analog connection to be directed at the public switched telephone network (PSTN’s) central office
B.the FXS interface connect directly to a standard telephone, fax machine, or sililar device and supplies ring, voltage, and dial tone
C.the FXS interface connect directly to an IP phone and supplies ring, voltage, and dial tone
D.the FXS interface connect directly to ISDN voice channels

微信掃碼免費(fèi)搜題