In VoIP, voice data is sent in packets by using IP instead of by traditional circuit transmissions or the circuit-switched telephone lines of the PSTN.是什么意思_In VoIP, voice data is sent in packets by using IP instead of by traditional circuit transmissions or the circuit-switched telephone lines of the PSTN.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句