Commuication problem

We have 1 SBS 2003 Server and 10 clients connected to server via Switch. Server have 2 NIC card in different networks. 1 NIC for Internal and 2 NIC for External which is in Router network.

Here, 8 machines are under the domain and getting IP from DHCP Server. The 2 are in Workgroup are assigned static IP address which is in Server network.

We have NAT enabled Router.
Our Problem is, Apache is running in one of my workgroup client system. The outside user accessing it. Is it possible for outside can able to access Apache, if I specify the workgroup Client IP address and Port address(running Apache Webserver) in NAT.[/b[/b]

Yes this should work and it sounds like you have the right idea about how to implement it, providing your server allows routing between the two NIC networks which I assume it does.
I'm not familiar with SBS though so I can't advise of the specific configuration you would use. Perhaps sopmeone else could?

Welcome to firewall.cx, sujo. It depends on which version of SBS 2003 you are running. If you have the Premium Edition which includes ISA 2004 (Microsoft's Firewall Server product), you will need to create a rule to forward the port in question to the internal machine. On the other hand, if you are running SBS 2003 Standard Edition, you will have to use the built-in Firewall which is similar to the one in Windows XP. In addition, whatever version of SBS 2003 you are running, you will need to configure your NAT router to forward the same port to the external NIC of your SBS 2003 server.

Ok Dalight, I will try that and let you know. Thank you very much for your quick response.

Now I am able to access the FTP on SBS 2003 server from Outside.

If I connect the External NIC directly to Router and Internal NIC and all other Client machines are connected to switch.

Then, If I configured NAT as you said, still the external user can able to access that Client (Apache Server) machine.

Please tell me, it works or not.

Your setup is OK i.e.

If I connect the External NIC directly to Router and Internal NIC and all other Client machines are connected to switch.

As I said before, you will need setup port forwarding at the NAT router as well as your server.