Communication Network System, Gateway, Data Communication Method and Program Providing Medium

1. A gateway, comprising: processing circuitry configured to instruct a user interface to communicate with two communication networks, instruct a storage device to accumulate, from a terminal connected to one of the two communication networks, program data executed at the terminal, receive device identification information and a license number of the program data, in response to requesting transmission of the license number, and determine whether or not the received device identification information and the received license number are allowed to receive the program data, based on previously stored device identification information of the terminal and license number of the program data, wherein a first of the two communication networks is a private communication network that enables only terminals within a specific communication area to communicate, a second of the two communication network is a public communication network that enables an indefinite number of users to communicate, the terminal is connected to the first of the two communication networks that is the private communication network, and the program data controls a function of the terminal.

2. The gateway of claim 1 , wherein the processing circuitry is further configured to instruct the storage device to accumulate backup data of data stored locally at the terminal.

3. A method comprising: instructing a storage device to accumulate, from a terminal connected to one of two communication networks, program data executed at the terminal, a first of the two communication networks being a private communication network that enables only terminals within a specific communication area to communicate, a second of the two communication network being a public communication network that enables an indefinite number of users to communicate, and the terminal being connected to the first of the two communication networks that is the private communication network; receiving device identification information and a license number of the program data, in response to requesting transmission of the license number, the program data controlling a function of the terminal; and determining whether or not the received device identification information and the received license number are allowed to receive the program data, based on previously stored device identification information of the terminal and license number of the program data.

4. The method of claim 3 , further comprising: instructing the storage device to accumulate backup data of data stored locally at the terminal.