Setup NAT for Public Access

Whatever service installed on a server will be available to the local network inside the organization only if the NAT(Network Address Translation) on modem is not properly set. This is how I Setup NAT on my UTI StarCom Modem provided by BSNL with their broadband (netone) connection.

1. From terminal/command prompt typed the command ipconfig/all and pressed enter key
2. Found the Default Gateway address from the list(e.g:- Default Gateway : 192.168.1.1)
3. Opened the web browser Mozilla Firefox/Internet explorer/Google Chrome/Any other
4. Typed the URL http://192.168.1.1 in the address bar and pressed enter (replace the default gateway address if required)
5. It prompted for the user id and password, entered it and pressed enter again
6. Selected Advanced setup->NAT from the left navigation menu
7. There are two options DMZ host and virtual servers, selected DMZ host and and typed the IP address of the system running the ftp/web/other service(e.g:-192.168.1.100)
8. Clicked Save/Apply button and then restarted my modem (not always required)
9. I checked my PC running the service for its IP address, for that I used the command ipconfig/all again from command propmt, it displayed my IP address as 192.168.1.4
10. Then I changed my IP to 192.168.1.100 by selecting My Network Places->View Network Connections->Local area connection->Properties->Internet Protocol(TCP/IP)->Properties->Use the following IP Address
11. Entered the IP 192.168.1.100 and subnet mask 255.255.255.0 and default gateway to 192.168.1.1, the same gateway address i got in step 2, clicked OK/Apply
12. The same gateway address is entered as Preferred DNS server
13. Now the service is available to the public