In the beginning, there was Internet !

The Internet is what we call the “network of networks”. But before going any further, what is a network ?

A network is a group of at least two computers that are connected together. In most cases, these computers are connected with each other through a switch, or hub, which enables information to be transmitted to the right computer or computers.

In larger networks, several switches/hubs are linked together.

What about the Internet ?

The Internet is really a set of networks that are connected to each other. These IP operator networks are what we call Autonomous Systems (AS), which are comprised of, for example, Internet Service Providers (such as Orange, Free and SFR), as well as hosts, large IP networks (such as Renater and Ampliva) and all other telecommunications operators that also have an IP business (such as France Telecom, SFR-Neuf-Cegetel...).

But how does it work when you send information (actually IP packets) to a machine that is located in a different AS?

There are two possibilities :

- The two Autonomous Systems may exchange their IP packets on a Global Internet Exchange (GIX).

- Or, the two Autonomous Systems are not linked to each other directly. In this case, traffic flows through larger operators known as transit providers,

who exchange the traffic between each other. This often takes place in exchange nodes, or they go one level higher until they reach an exchange node.

It is therefore easy to understand the advantage of an exchange node that limits the number of intermediaries necessary for transporting information from source to destination.

Is the IP operator that you use, professionally or privately, connected to our GIX ?

If after all this you still do not understand what a is GIX, you can view this short film explaining What is an IX made for competition organized by Euro-IX.