Is it possible to connect to a device (laptop, smartphone) using its external ip?

Question

Computer networks

Hello. Perhaps a stupid question, but is it possible, knowing the external ip address of the device, for example, to enter it in the browser line and get some kind of response from this device? Of course, provided that a process is running on this very device that listens to this ip address and sends a response when connected to it.
those. Will this device be visible on the Internet? Or maybe you need to register it somehow to get access to it?
PS This behavior is implemented, but within the local network. When I try to connect via external ip nothing happens.

Thanks in advance to everyone who answers!

Answer 1

Yes, you don't need to register anything.
Works right out of the box.

This behavior is implemented, but within the local network. When I try to connect via external ip nothing happens.

How do you do it? Your device has two network cards, one of them has local ip and the other is external?
1) Check that your external IP is really white (real)
2) Make sure that your external IP is assigned to your device, not to the router.
3) Make sure the firewall is not blocking access.

Answer 2

if a device with an external ip is not hidden behind a firewall/nat and listens to requests via http/https, why not?

Answer 3

Maybe you should set up a VPN?