How to Configure the Modem and Serial Port on a Dial-In Server
Note - PPP was removed in the Oracle Solaris 11.4 SRU 24 release.
- Program the modem, as
instructed in the modem manufacturer's documentation.For
other suggestions, refer to How to Configure the Modem and Serial Port on a Dial-Out System. 
- Attach the modem to the
serial port on the dial-in server.
- Become an administrator on the dial-in server.
For more information, see Using Your Assigned Administrative Rights in Securing Users and Processes in Oracle Solaris 11.4. 
- Specify modem direction as dial-in only.