The role of Router port mapping and its configuration in Cisco devices

The port Mapping method enables access to specific port services from the Internet to the local area network internal machines. For example, the machine you are using is in a LAN connected to the Internet, all the services you open on the machine (such as FTP), by default, the outside world can not access. This is because your IP is the LAN internal IP, and the outside can access only the server you are connected to the IP, because the entire LAN on the Internet only a real IP address, and this IP address is a local area network server unique. Therefore, the external Internet logon can only find servers in the local area network, then the services you provide will certainly not work.

So the way to solve this problem is to use PM.

Port mapping in Cisco device configuration:

router(config)#ip nat inside source static tcp 10.10.10.1 22 210.10.8.1 22 extendable
router(config)#ip nat inside source static tcp 10.10.10.2 80 210.10.8.1 80 extendable