The request to the
CheckIP service is executed on your server. In that case your server is the
client for which the IP address is returned.
Note also that such services are only useful when behind a router that performs network translations. Otherwise, the IP is the same as for the local network interface.
If you want to get the IP address of a connected client on a server, just get that information from the socket using the
Socket.RemoteEndPoint Property (System.Net.Sockets)[
^].