Data Processing

There are two types of IP addresses: Public and Private. Public address given to you by your Internet Service Provider (ISP) you use to connect to the Internet. For the hosts within organizations that do not require direct access to the Internet, IP addresses are not to duplicate public addresses that have been given is needed.

To solve this problem addresses, the Internet designers reserve a portion of the IP address space and the naming of this space as a private address space. An IP address in private address space is never given as a general address. IP addresses in private address space known as private addresses. Using private IP addresses, you can provide protection from network hackers.

Because IP addresses on the private address space will never be provided by the Internet Network Information Center (InterNIC) as a general address, then the route in the Internet router to a private address will never exist. Private addresses can not be reached on the Internet.

Therefore, when using private IP addresses, you need some type of proxy or a server to convert a number of private IP addresses on your local network into public IP addresses that can be routed. Another option is to translate private addresses into public addresses are valid with the network address translator (NAT) before it is sent on the Internet. Support for NAT to translate public addresses and private addresses allows the connection networks, home office or small office to the Internet.

NAT hides the IP addresses that are managed internally from external networks by translating private internal addresses to public external addresses. This reduces the cost of the registration IP addresses by allowing their customers to use unregistered IP addresses internally, through a translation into a small number of registered IP addresses externally. It also hides the internal network structure, reducing the risk of denial of service attacks against internal systems.