How to communicate with ARDUINO ETHERNET Shield over the internet? (What IP adre


I've successfully tested my Ethernet shield within my home network. The IP I used for the shield was My question is how to access my shield from other computers around the internet? What IP should I set? I have got a static IP from my internet provider, but when I use it I can't connect to the shield. Please help..

Have you got port forwarding on your router?

BTW, posting the same question over and over again on the forum is a fast-track to a banning.


I’m going to assume that you know the difference between local IP and public IP.

You need the public IP of the router where your arduino is connected to. Lets Imagine your public IP is (which is different from your local IP

If your Ethernet shield is listening by the port, lets say, 4455, you have to forward that port to in your router.

And then, from another PC (outside of LAN) you will need to do something like this,

Client.connect(, 4455) // PublicIP, Port

Note that this is just pseudocode

your arduino will recieve the hello string.

Thank you guys, this solved my problem. And sorry for cross posting :p