NAT and PAT technology is used to replace an Internet Protocol address (IP address) with IP data packets. But what exactly is it, how does it work and how secure is this solution?

What is NAT?

Network Address Translation (NAT) acts as a translation of an IP address used in one network into another IP address used in a different network. It converts a public IP address into several private IP addresses. Each outgoing connection is read with an IP address and port number. The NAT can then use the specified port number to assign incoming data to a local station. However, this assignment is only valid for a short time.

A distinction is also made between source NAT (SNAT) and destination NAT (DNAT). With a SNAT, the source address is exchanged, which is typical for private Internet access. However, a destination NAT (DNAT) is used to change the destination of an IP packet. The DNAT is usually used to change a public IP of an Internet connection to a private IP address of a server in the private subnet. SNAT and DNAT can be used individually or together for an IP packet.

What is PAT?

Port address translation enables several devices in a local area network (LAN) to be mapped to a single public IP address. This technology is therefore an extension of NAT. In this way, many IP addresses are saved. PATs are used in most home networks.

How safe is this technology?

In terms of IT security, there are few security concerns with NAT. As the end devices are hidden behind a router, i.e. in a private network, from the public Internet, the systems cannot be reached from the Internet. A direct Internet connection is only required when the end devices establish a connection. Although this technology cannot replace a fully-fledged firewall or packet filter, the protection is comparable to a rudimentary firewall.

If you have any questions about more detailed information on these techniques, the b.r.m. staff will be happy to help. You can also read more on this website.