Network Address Translation

In Computer Networking, the process of Network Address Translation (NAT, also known as Network Masquerading, Native Address Translation or IP Masquerading) involves re-writing the source and/or destination addresses of IP packets as they pass through a Router or firewall. Most systems using NAT do so in order to enable multiple hosts on a private network to access the Internet using a single public IP address (see gateway). Many network administrators find NAT a convenient technique and use it widely. Nonetheless, NAT can introduce complications in communication between hosts and may have a performance impact.

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