Sun solaris to access Internet

We’re using ISDN to access Internet.
Can anyone help me to configure my Sun Solaris 8 to access to the Internet.
My gateway is 192.168.4.1
My Sun system IP address is 192.168.4.40
My network IP address is 192.168.4.0
My ISP DNS server IP address is 202.188.1.5
Pls advise where to set and configure.

thks