After reading this guide is really easy to setup a PPP link between HPUX and a remote system via modem. Only one question: i know the ip address of the remote system and my local ip(192.168.31.1 and 192.168.32.105) so I edit the /etc/ppp/autostart file like this
pppd 192.168.31.105:192.168.32.1 auto idle 3600
The question is: is possible to tell ppp to get ip automatically from remote system as Windows and Linux does?
I have tried
pppd 0:0 auto idle 3600
pppd 0.0.0.0:0.0.0.0 auto idle 3600
but both failed.