I have two internet lines, what I need to do is, have a one Linux server and convert it to a proxy server (with a firewall) for both of two internet lines.

And there should be two different configurations for both lines. (I’ll be able to configure which computer having leased line internet connection and which computer should have DSL internet connection in my network. The network has 30 machines, and all are on NT 2000 platform)

Is there any relevant software for doing such operations or give me your ideas, related links and stuff will be highly appreciated.

Please try to brief more simplify since I’m not an expert on Linux.

Thanking you all !

Nuwan