Can someone clarify this for me... Ive just gone over an explination of class IP addresses from my training material and got confused. Managed to sort some of it out but am still slightly confused. The class addresses were explained fairly simple like this: Class A IP address Range 1 - 126 Class B Range 128-191 Class C Range 192-223 The next chapter explained about subnets which clarified a few things.... however, I was under the impression that the Internet used all class A, and class B and C were used for smaller networks. That means that all IP addresses on the internet have to be in the 1 to 126 range? So why is my own IP address 193.*.*.* and on a site I have IP access to I can see logins from 4.* to 208.* (and that is just a quick sample of 10 logins!). Surely mine is a class C address? I am aware that the netmask has a lot to play on it... depending on what it is set as (ie class C is 255.255.255.0). Is it not as simple as the nice table they gave us with ranges on? Can any class use any range now (apart from specificaly reserved ones like 127.* and in my knowledge 192.*) and its all down to the netmask what type of class it is? Thanks.... I hope that all makes sence!