Dial up, type "slip" at the prompt, enter your machine name and
password. The things you need to enter depends on your
environment. I use kermit, with a script like this:
# kermit setup
set modem hayes
set line /dev/modem
set speed 115200
set parity none
set flow rts/cts
set terminal bytesize 8
set file type binary
# The next macro will dial up and login
define slip dial 643-9600, input 10 =>, if failure stop, -
output slip\x0d, input 10 Username:, if failure stop, -
output silvia\x0d, input 10 Password:, if failure stop, -
output ***\x0d, echo \x0aCONNECTED\x0a
(of course, you have to change the hostname and password to fit
yours). Then you can just type "slip" from the kermit prompt to
get connected.
Note: leaving your password in plain text anywhere in the
filesystem is generally a BAD idea. Do it at your own risk. I'm
just too lazy.