The router has to be configured to send the data to a <IP address> : <port>, and the web host has to open the <IP address> : <port> to accept connections. Have a script (daemon) that keeps listen to the <IP address> : <port>, parse incoming data and you can store it somewhere.
It requires socket function, listen either TCP or UDP depending how the router sends the data. Google / github for TK 102, and you can find examples on how to implement it in various languages. TK 102 is a popular GPS tracker model.
If you are tracking many trackers, I would suggest Node.js over PHP for the daemon.