US Patent 7889852 Remote communications with a vending machine using call back

In a communications system, a computer network server (2) is arranged to communicate simultaneously with a plurality of remote computers 201 . . . 20n. A remote embedded application in the form of a vending machine (1) has a module (12) that is arranged to communicate with the computer network server (2) such that file transfer sessions are carried out between the server and the vending machine (1). The server (2) is arranged to cause call request data to be transmitted to the module (12) and the module (12) is arranged to initiate a call back to the server (2) or other designated server, in response to the call request data. The call request data is transmitted using calling line identification (CLI). The module (12) is arranged to detect the call and the CLI; to not answer the call; and to initiate a call back to the server (2) or other designated server, after having received the call with CLI. The call request data may alternatively be transmitted to the module (12) in the form of a short message service (SMS) message.