Do you need an FXS of FXO gateway ?

Do you need an FXS gateway or an FXO gateway?

If you want to connect an analog fax machine to the phone system, you will need at least one FXS port. If you want to use analog telephone lines with your phone system, you need one FXO port per line.
Read all about it in this article:
https://cnto.io/DroGhQNjP