If you want to connect with a PPP connection there is a simple
slip script which can be used. In the /usr/lib/ppp directory
is a README.linux which can explain what I am going to give
you.
ppp connect 'chat -v "" ATDT(PHONE #) CONNECT "" ogin: (login)
word: (password) ' /dev/modem(or your com port device) 38400
debug crtscts modem defaultroute
refer to that document referred to above and you will have a
PPP connection that if a little static routing is invoked will
give you a ip forwarding if your kernel is configured to do so.
Also if you put this command in the inittab in the respawn
section( another matter in itself) this will keep your
connection alive. I use this for my linux box which is my IP
router for my network at my apartment.