Light up LED when there is a call on the phone

hello guys, (sry for my english i'm from France)
I'm mainly a php dev, and i want to develop a code for my arduino/ethernet shield to light up a LED if someone is calling on the phone.

At the moment i have the code of the example : Web Server who works.

So where should i start in yout opinion?

My idea was to find a way to send a request to the ip adress of my arduino, and in the block loop{} check if something was send to him.

If the request == the conditions, i light up a led for X second, if no request i break and restart the loop until there is the request i want.

This is the good way to do it ? I'm not sure if i'm clear in my explanation.

thank you guys.

hello guys, (sry for my english i'm from France)

There IS a French section of the forum.

i want to develop a code for my arduino/ethernet shield to light up a LED if someone is calling on the phone.

How is the phone connected to the Arduino? Or, is it attached to the Ethernet shield?

So where should i start in yout opinion?

With explaining just how the Arduino is supposed to know anything about the phone.