A router exposes itself to outside by IP like
18.104.22.168 and many hosts can connect to it to form a Local Area Network.
My question :
Is there a way to identify a specific host in that LAN?
All I tried is some guessing work which fails with no doubt:
ping email@example.com Ping request could not find host firstname.lastname@example.org. Please check the name and try again.
I think since each host in LAN can get their packets from outside the router,there MUST be a way to identify each host,but what's that?
UPDATE How to achieve Port forwarding except configuring it in the router?
Now I think UPnP is the way to go,but is there a working sample for this?