Terminal Device, System, Connection Management Server, and Computer Readable Medium

• US 20100228978A1
• Filed: 02/26/2010
• Published: 09/09/2010
• Est. Priority Date: 03/06/2009
• Status: Active Grant

• Current Assignee: Brother Kogyo Kabushiki Kaisha
• Original Assignee: Brother Kogyo Kabushiki Kaisha
• Inventors: KUDO, Yasuhiro
• Granted Patent: US 8,874,911 B2
• Time in Patent Office: Days
• US Class Current: 713/168
• CPC Class Codes: H04L 61/2546 Arrangements for avoiding unnecessary translation
• CPC Class Codes: H04L 61/2564 for a higher-layer protocol, e.g. for session initiation protocol [SIP]
• CPC Class Codes: H04L 61/2575 using address mapping retrieval, e.g. simple traversal of user datagram protocol through session traversal utilities for NAT [STUN]
• CPC Class Codes: H04L 61/2578 without involvement of the NAT server
• CPC Class Codes: H04L 63/06 for supporting key management in a packet data network cryptographic mechanisms or cryptographic arrangements for key management H04L9/08
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]

Abstract

A second terminal device is used in a system including a connection management server, a first terminal device, and the second terminal device. The second terminal device includes: a local address obtaining unit configured to obtain a first local IP address and first authentication information of the first terminal device from the connection management server, if a first global IP address matches a second global IP address; a determination unit configured to determine, by using of the obtained first authentication information, whether a first particular terminal device with which the second terminal device can communicate by use of the first local IP address is the first terminal device; and a target data communication unit configured to communicate first data with the first terminal device by using the first local IP address, if the first particular terminal device is determined to be the first terminal device.

Claims

1. A second terminal device used in a system that comprises a connection management server, a first terminal device, and the second terminal device, said second terminal device comprising:

a local address obtaining unit configured to obtain a first local IP address and first authentication information of the first terminal device from the connection management server in which the first local IP address and the first authentication information are registered, if a first global IP address of the first terminal device matches a second global IP address of the second terminal device;

a determination unit configured to determine, by using of the obtained first authentication information, whether a first particular terminal device with which the second terminal device can communicate by use of the first local IP address is the first terminal device; and

a target data communication unit configured to communicate first data with the first terminal device by use of the first local IP address, if the determination unit determines that the first particular terminal device is the first terminal device.

2. The device according to claim 1, further comprising:

a global address obtaining unit configured to obtain a set of the first global IP address and a port number of the first terminal device,

wherein if the determination unit determines that the first particular terminal device is not the first terminal device, the target data communication unit communicates second data with the first terminal device by use of the set of the first global IP address and the port number.

3. The device according to claim 1, further comprising:

a first challenge data communication unit configured to transmit first challenge data to the first particular terminal device and to receive first response data transmitted by the first particular terminal device in response to the first challenge data, the first response data being generated by encrypting the first challenge data,

wherein the first authentication information includes a first public key of the first terminal device, and

wherein the determination unit decrypts the first response data using the first public key so as to generate first decrypted data, and if the first decrypted data matches the first challenge data, the determination unit determines that the particular first terminal device is the first terminal device.

4. The device according to claim 3, wherein if the first response data are not received by the first challenge data communication unit, the determination unit determines that the particular first terminal device is not the first terminal device.

5. The device according to claim 1, further comprising:

a storage control unit configured to hold the first local IP address in a storage unit,

wherein when third data are to be communicated with the first terminal device after completion of the communication of the first data, the target data communication unit communicates the third data with the first terminal device by using again the first local IP address held in the storage unit.

6. The device according to claim 5,

wherein the storage control unit further holds the first authentication information in the storage unit,

wherein when the third data are to be communicated with the first terminal device after the completion of the communication of the first data, the determination unit determines, by use of the first authentication information held in the storage unit, whether a particular second terminal device with which the second terminal device can communicate by use of the first local IP address held in the storage unit is the first terminal device, and

wherein if the determination unit determines that the particular second terminal device is the first terminal device, the target data communication unit communicates the third data with the first terminal device by using again the first local IP address held in the storage unit.

7. The device according to claim 1, further comprising:

a public key transmission unit configured to transmit a second public key of the second terminal device to the first terminal device if the determination unit determines that the particular first terminal device is the first terminal device; and

a second challenge data communication unit configured to;

receive second challenge data that is transmitted by the first terminal device to the second local IP address of the second terminal device as a destination;

encrypt the second challenge data using a secret key of the second terminal device so as to generate second response data; and

transmit the second response data to the first terminal device,

wherein if second decrypted data matches the second challenge data, the target data communication unit communicates fourth data with the first terminal device by use of the second local IP address, wherein the second decrypted data is generated by the first terminal device by decrypting the second response data by use of the second public key.

8. A system comprising:

a connection management server;

a first terminal device; and

the second terminal device according to claim 1.

9. A connection management server used in a system that comprises the connection management server, a first terminal device and a second terminal device, said connection management server comprising:

a server-side storage control unit configured to hold a first global IP address, a first local IP address, and first authentication information of the first terminal device in association with one another in a server-side storage unit;

a server-side receiving unit configured to receive a connection request that is transmitted by the second terminal device to the first terminal device as a destination and that includes a second global IP address of the second terminal device;

a server-side determination unit configured to determine whether the first global IP address of the first terminal device held in the server-side storage unit matches the second global IP address of the second terminal device included in the connection request; and

a server-side transmission unit configured to transmit the first local IP address and the first authentication information of the first terminal device held in the server-side storage unit to the second terminal device if the server-side determination unit determines that the first global IP address matches the second global IP address.

10. The server according to claim 9, further comprising a server-side transfer unit configured, if the server-side determination unit determines that the first global IP address does not match the second global IP address, to transfer the connection request to the first terminal device.

11. A computer readable medium having a computer program for a second terminal device used in a system that comprises a connection management server, a first terminal device, and the second terminal device, said computer program being stored on the computer readable medium, readable by a computer, and causing, when executed by a computer, the computer to perform operations comprising:

obtaining a first local IP address and first authentication information of the first terminal device from the connection management server in which the first local IP address and the first authentication information are registered, if a first global IP address of the first terminal device matches a second global IP address of the second terminal device;

determining, by using of the obtained first authentication information, whether a first particular terminal device with which the second terminal device can communicate by use of the first local IP address is the first terminal device; and

communicating first data with the first terminal device by use of the first local IP address, if the first particular terminal device is determined to be the first terminal device.

12. A second terminal device used in a system that comprises a connection management server, a first terminal device, and the second terminal device, said second terminal device comprising:

a local address obtaining unit configured to obtain a first local IP address from the connection management server in which the first local IP address of the first terminal device is registered;

a first target data communication unit configured to communicate first data with the first terminal device by use of the obtained first local IP address if a first global IP address of the first terminal device matches a second global IP address of the second terminal device; and

a second target data communication unit configured to communicate second data with the first terminal device by use of the first global IP address of the first terminal device if the first global IP address of the first terminal device does not match the second global IP address of the second terminal device.