PaulS:
in my project I have to visualize the output of the arduino in a website that is in the intranet
Visualize it how? It seems to me that, in your case, the Arduino should be wearing an Ethernet shield, and should be acting as a server. It should NOT be pushing information anywhere.
this is exactly what I proposed, but for now I have an application desktop in c# and I can see the output of the Arduino using a simple program , how will be the procedure for storing the output of the arduino every once in a database if I use with the ethernet shield??