Asterisk (at least on version 17) support old rotary phones without problems (with option pulsedial=yes ). I have tested with success three rotary phones.
My phone company support pulsedial (is the only one in my country as I know), even in fttc (ftth not tested).
My fast question is this: if one day, the ftth arrive in my city, or the company phone drop the pulsedial/rotary support, it will possible to use those phones in asterisk?
I explain better
The situation now (working)
---> = connected to
rotaryphone---->Asterisk---->VOIPROUTER--->FTTCROTARYSUPPORTED
The situation in the future
rotaryphone---->Asterisk---->VOIPROUTER--->FTTH?
Consider asterisk is connected to voiprouter as a “ip phone” so it use the sip protocol.
So As I suspect the “pulse/analogic” is converted to modern “voip” by asterisk and can comunicate with modern lines?
Very good news, long live to rotary phones
It’s converted to digits by the DAHDI channel driver, and converted to VoIP by the the chan_pjsip channel driver.
Note that, as far as I know, this only applies to call set up. In some countries, a pulse dialled one is indistinguishable from a recall signal, so trying to generally replace pulse dialling with tones would be difficult. I believe that DAHDI can be configured to treat recall as the start of a transfer, but the Asterisk core sees a transfer request, not individual digits.
Asterisk is a back to back user agent, so it handles the analogue side as an analogue call, with the option of pulse dialling, and creates a new call on the VoIP side with initial digits in the INVITE request.