Cisco has created some NAT terminology which explicitly refer to the IP addresses and/or ports involved in Network Address Translation (NAT). While discussing the addresses involved in a NAT, using the terms like “Source” and “Destination” are common. However, using such terms can create some ambiguity. Specifically, the terms “Source” and “Destination” can create confusion […]
Network Address Translation (NAT)
November 8, 2017 By 6 Comments
Every device on the Internet has an IP address. The IP address serves as the device’s identification – much like how a phone number identifies a particular phone. When devices communicate on the Internet, they are sending data from their IP address to the IP address of their intended destination. Sometimes, while data is en […]
NAT Terminology Disambiguation
November 5, 2017 By 12 Comments
If you’ve made it here, then at this point you should have a solid understanding of each of the four types of translation that can exist: Static NAT, Static PAT, Dynamic PAT, and Dynamic NAT. Moreover, you have an understanding of Policy NAT and Twice NAT, which are simply two different ways of implementing the […]
Policy NAT and Twice NAT
November 1, 2017 By 7 Comments
Every type of NAT we have discussed so far have two things in common. The first is that only the source of the packet is used to make a NAT decision. The second is that only the source of the outbound packet is translated. Policy NAT and Twice NAT are two ways of performing any […]
Dynamic NAT
October 25, 2017 By 5 Comments
According to the definitions outlined in the NAT Terminology article, a Dynamic NAT implies a translation of just the IP address, where the post-translation attributes are selected by the router. In a Dynamic NAT, a multitude of hosts with private IP addresses can share an equal or fewer amount of public IP addresses. It may […]
Dynamic PAT
October 18, 2017 By 9 Comments
According to the definitions outlined in the NAT Terminology article, a Dynamic PAT implies a translation of the IP address and Port, where the post-translation attributes are selected by the router. Dynamic PAT is the most common of the types of address translation we will discuss in this article series. Dynamic PAT is used any […]
Static PAT
October 11, 2017 By 9 Comments
According to the definitions outlined in the NAT Terminology article, a Static PAT implies a translation of the IP address and Port, where the post-translation attributes are explicitly defined. There are multiple use cases for a Static PAT, but they all have one thing in common – a need to manually change the TCP or […]
Static NAT
October 4, 2017 By 2 Comments
According to the definitions outlined in the NAT Terminology article, a Static NAT implies a translation of just the IP address, where the post-translation IP addresses are explicitly defined. Making Internal Resources Accessible The typical use case for a Static NAT is for a Server on a Private IPv4 network to be reached externally from the […]