NAT concepts

Before we start to talk about NAT concepts, let's understand what kind of problems it solves. Let's think of a small company with a network of 10 devices and all of them need to be connected directly to the internet. We are talking about a small company with a limited budget, so the available WAN connection has only one public Internet Protocol (IP) address and there is no possibility to get an upgrade to a service that provides an entire IP network range. Sound familiar? In Brazil and Portugal, this scenario is very common. So, how do we connect all those devices using a single public IP address? If you answered using NAT, you're right! This is one of the most common scenarios for using NAT. Another one is when you need to provide, let's say, web services, but you have more web servers than available public IP addresses. In this case, NAT can help too, by using different ports of the same IP address. But what is the difference between these two examples...