The modem modulates the binary data into an analog signal at the source and demodulates the analog signal at the destination to binary data. 數據機在來(lái)源端調變二進(jìn)位的資料進(jìn)入的類(lèi)比信號內并且在目的端解調這個(gè)類(lèi)比信號成為二進(jìn)位的資料。
When intermittent, low-volume data transfers are needed, modems and analog dialed telephone lines provide low capacity and dedicated switched connections. 當間歇性，低量的資料傳輸被需要時(shí)，數據機和類(lèi)比的撥號電話(huà)線(xiàn)提供了低容量且專(zhuān)用的交換連接。
