Data communication system, information processing device and method, recording medium and program

An information processing device which is connected to a server concerned with sales of content data via a network, said information processing device comprising:

• random-number generation means for generating a random number;
• generation means for generating first and second signals;
• encryption means for encrypting a data sequence;
• transmission means for transmitting said data sequence encrypted by said encryption means to said server via said network;
• setting means for setting stored content data from an ineffective state to an effective state;
• and
• control means for controlling said random-number generation means, said generation means, said encryption means, said transmission means, and said setting means,
• wherein, after said control means repeats a process for transmitting said the first signal and said first random number, which are encrypted, to said server via said network for a random number of times, said control means sets said content data from the ineffective state to the effective state, and transmits said second signal and said second random number, which are encrypted, to said server via said network.

An information processing method for use with an information processing device which is connected via a network to a server concerned with sales of content data, said information processing method comprising:

• a random-number generation step of generating a random number;
• a generation step of generating first and second signals;
• an encryption step of encrypting a data sequence;
• a transmission step of transmitting said data sequence encrypted in the process of said encryption step to said server via said network;
• a setting step of setting stored content data from an ineffective state to an effective state;
• and
• a control step of controlling said random-number generation step, said generation step, said encryption step, said transmission step, and said setting step,
• wherein, in said control step, after a process for transmitting said the first signal and said first random number, which are encrypted, to said server via said network is repeated a random number of times, said content data is set from the ineffective state to the effective state, and said second signal and said second random number, which are encrypted, are transmitted to said server via said network.

A recording medium having recorded thereon a computer-readable program used to control a client terminal which is connected via a network to a server concerned with sales of content data, said program comprising:

• a random-number generation step of generating a random number;
• a generation step of generating first and second signals;
• an encryption step of encrypting a data sequence;
• a transmission step of transmitting said data sequence encrypted in the process of said encryption step to said server via said network;
• a setting step of setting stored content data from an ineffective state to an effective state;
• and
• a control step of controlling said random-number generation step, said generation step, said encryption step, said transmission step, and said setting step,
• wherein, in said control step, after a process for transmitting said the first signal and said first random number, which are encrypted, to said server via said network is repeated a random number of times, said content data is set from the ineffective state to the effective state, and said second signal and said second random number, which are encrypted, are transmitted to said server via said network.

A program for allowing a computer to execute, which computer is connected via a network to a server concerned with sales of content data:

• a random-number generation step of generating a random number;
• a generation step of generating first and second signals;
• an encryption step of encrypting a data sequence;
• a transmission step of transmitting said data sequence encrypted in the process of said encryption step to said server via said network;
• a setting step of setting stored content data from an ineffective state to an effective state;
• and
• a control step of controlling said random-number generation step, said generation step, said encryption step, said transmission step, and said setting step,
• wherein, in said control step, after a process for transmitting said the first signal and said first random number, which are encrypted, to said server via said network is repeated a random number of times, said content data is set from the ineffective state to the effective state, and said second signal and said second random number, which are encrypted, are transmitted to said server via said network.

An information processing device for communicating information related to content data with a client terminal connected via a network, said information processing device comprising:

• decryption means for decrypting a data sequence received from said client terminal via said network;
• sending-back means for sending back, to said client terminal via said network, a data sequence contained in the decrypted result of said decryption means;
• and
• billing means for performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result of said decryption means.

An information processing method for use with an information processing device for communicating information related to content data with a client terminal connected via a network, said information processing method comprising:

• a decryption step of decrypting a data sequence received from said client terminal via said network;
• a sending-back step of sending back, to said client terminal via said network, a data sequence contained in the decrypted result in the process of said decryption step;
• and
• a billing step of performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result in the process of said decryption step.

A recording medium having recorded thereon a computer-readable program for controlling a server which communicates information related to content data with a client terminal connected via a network, said program comprising:

• a decryption step of decrypting a data sequence received from said client terminal via said network;
• a sending-back step of sending back, to said client terminal via said network, a data sequence contained in the decrypted result in the process of said decryption step;
• and
• a billing step of performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result in the process of said decryption step.

A program for allowing a computer to execute, which computer communicates information related to content data with a client terminal connected via a network:

• a decryption step of decrypting a data sequence received from said client terminal via said network;
• a sending-back step of sending back, to said client terminal via said network, a data sequence contained in the decrypted result in the process of said decryption step;
• and
• a billing step of performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result in the process of said decryption step.

An information processing device which is connected to a server concerned with sales of content data via a network, said information processing device comprising:

• storage means for storing content data;
• generation means for generating a request for transmitting right data corresponding to said content data;
• decryption means for decrypting and storing a data sequence from said server via said network;
• and
• transmission means for transmitting the decrypted result of said decryption means to said server via said network, said decoded result being encrypted in such a manner as to be contained in said transmission request.

An information processing method for use with an information processing device which is connected to a server concerned with sales of content data via a network, said information processing method comprising:

• a storage step of storing content data;
• a generation step of generating a request for transmitting right data corresponding to said content data;
• a decryption step of decrypting and storing a data sequence from said server via said network;
• and
• a transmission step of transmitting the decrypted result in the process of said decryption step to said server via said network, said decoded result being encrypted in such a manner as to be contained in said transmission request.

A recording medium having recorded thereon a computer-readable program for controlling a client terminal which is connected via a network to a server concerned with sales of content data, said program comprising:

• a storage step of storing content data;
• a generation step of generating a request for transmitting right data corresponding to said content data;
• a decryption step of decrypting and storing a data sequence from said server via said network;
• and
• a transmission step of transmitting the decrypted result in the process of said decryption step to said server via said network, said decoded result being encrypted in such a manner as to be contained in said transmission request.

A program for allowing a computer to execute, which computer is connected via a network to a server concerned with sales of content data:

• a storage step of storing content data;
• a generation step of generating a request for transmitting right data corresponding to said content data;
• a decryption step of decrypting and storing a data sequence from said server via said network;
• and
• a transmission step of transmitting the decrypted result in the process of said decryption step to said server via said network, said decoded result being encrypted in such a manner as to be contained in said transmission request.

An information processing device for transmitting, via a network, right data corresponding to content data to a client terminal storing the content data, said information processing device comprising:

• random-number generation means for generating a random number;
• encryption means for encrypting a data sequence;
• transmission means for transmitting said data sequence encrypted by said encryption means to said client terminal via said network;
• decryption means for decrypting a data sequence received from said client terminal via said network;
• billing means for performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result of said decryption means;
• and
• control means for controlling said random-number generation means, said generation means, said encryption means, said transmission means, said decryption means, and said billing means,
• wherein said control means repeats a process for transmitting dummy data, which is encrypted, formed of a random number to said server via said network and for confirming that said dummy data is contained in the response from said client terminal for a random number of times, said right data, which is encrypted, is transmitted to said client terminal via said network, and after confirming that said right data is contained in the response from said client terminal, a billing process for a user of said client terminal is performed.

An information processing method for use with an information processing device for transmitting right data corresponding to content data to a client terminal storing the content data via a network, said information processing method comprising:

• a random-number generation step of generating a random number;
• an encryption step of encrypting a data sequence;
• a transmission step of transmitting said data sequence encrypted in the process of said encryption step to said client terminal via said network;
• a decryption step of decrypting a data sequence received from said client terminal via said network;
• a billing step of performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result in the process of said decryption step;
• and
• a control step of controlling said random-number generation step, said encryption step, said transmission step, said decryption step, and said billing step,
• wherein, in said control step, after a process for transmitting dummy data, which is encrypted, formed of a random number to said client terminal via said network and for confirming that said dummy data is contained in the response from said client terminal is repeated a random number of times, said right data, which is encrypted, is transmitted to said client terminal via said network, and after confirming that said dummy data is contained in the response from said client terminal, a billing process for a user of said client terminal is performed.

A recording medium having recorded thereon a computer-readable program for controlling a server which transmits right data corresponding to content data to a client terminal storing said content data via a network, said program comprising:

• a random-number generation step of generating a random number;
• an encryption step of encrypting a data sequence;
• a transmission step of transmitting said data sequence encrypted in the process of said encryption step to said client terminal via said network;
• a decryption step of decrypting a data sequence received from said client terminal via said network;
• a billing step of performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result in the process of said decryption step;
• and
• a control step of controlling said random-number generation step, said encryption step, said transmission step, said decryption step, and said billing step,
• wherein, in said control step, a process for transmitting dummy data, which is encrypted, formed of a random number to said server via said network and for confirming that said dummy data is contained in the response from said client terminal is repeated a random number of times, said right data, which is encrypted, is transmitted to said client terminal via said network, and after confirming that said right data is contained in the response from said client terminal, a billing process for a user of said client terminal is performed.

A program for allowing a computer to execute, which computer transmits right data corresponding to content data to a client terminal storing said content data via a network:

• a random-number generation step of generating a random number;
• an encryption step of encrypting a data sequence;
• a transmission step of transmitting said data sequence encrypted in the process of said encryption step to said client terminal via said network;
• a decryption step of decrypting a data sequence received from said client terminal via said network;
• a billing step of performing a billing process for a user of said client terminal in such a manner as to correspond to the decrypted result in the process of said decryption step;
• and
• a control step of controlling said random-number generation step, said encryption step, said transmission step, said decryption step, and said billing step,
• wherein, in said control step, after a process for transmitting dummy data, which is encrypted, formed of a random number to said server via said network and for confirming that said dummy data is contained in the response from said client terminal is repeated a random number of times, said right data, which is encrypted, is transmitted to said client terminal via said network, and after confirming that said dummy data is contained in the response from said client terminal, a billing process for a user of said client terminal is performed.