Vitalik Buterin: @TrustlessState 这是因为在过去的好日子里，人们会从字面上使用 SMS 确认码协议的音频版本来相互进行语音通话。

原推：@TrustlessState It’s because in the good old days, people would literally use the audio version of the SMS confirmation code protocol to have voice calls with each other.
https://twitter.com/VitalikButerin/status/1602094685916463104