Linus internet connection sharing?

[shakti]

I have read abt firewall myself and all sever configuration.
But i can't do internet sharing
Please some one guide me how to do internet connection sharing through linux server.

[alc6379]

Try this:

http://www.tldp.org/HOWTO/IP-Masquerade-HOWTO/

This explains how to use Network Address Translation to share an Internet connection.