Communication Apparatus

• US 20080072046A1
• Filed: 09/06/2005
• Published: 03/20/2008
• Est. Priority Date: 09/07/2004
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Ayaki, Yasushi, Iitsuka, Hiroyuki, Usuki, Naoshi
• Granted Patent: US 8,341,701 B2
• Time in Patent Office: Days
• US Class Current: 713/171
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 43/0864 Round trip delays
• CPC Class Codes: H04L 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 9/3271 using challenge-response
• CPC Class Codes: H04W 8/04 Registration at HLR or HSS [Home Subscriber Server]

Abstract

The conventional data transmitting/receiving system has problems: that a correct measurement cannot be performed because a measurement result is an addition of a verification processing time and a transmission time; that an authentication processing which is necessary for a transmission time measurement processing needs to be separately required; and that an unnecessary key exchange processing is executed. The transmission apparatus (a) shares authentication information with a request source which requests for transmission of content data, (b) transmits, to the request source, a measurement request generated using the authentication information, (c) receives, from the request source, a measurement response generated using the authentication information by the request source, as a response to the measurement request, (d) measures the period of time from the transmission of the measurement request to the reception of the measurement response, as a round trip time, (e) transmits, to the request source, a measurement preparation request for a preparation which is necessary for generating the measurement response, before the transmission of the measurement request, and (f) determines that the request source is an eligible device as the transmission destination of the content data, after the measurement of the round trip time, in the case where it is confirmed that the round trip time is less than or equal to a reference value, the measurement response is verified as a correct response, and the measurement request is verified as a correct request by the request source.

Claims

1. A communication apparatus which responds to a request for transmission of content data, said apparatus comprising:

an authentication unit operable to share authentication information with a request source which requests for the transmission of the content data;

a measurement request transmitting unit operable to transmit, to the request source, a measurement request which is generated using the authentication information;

a measurement response receiving unit operable to receive, from the request source, a measurement response which is generated using the authentication information by the request source, as a response to the measurement request;

a round trip time measurement unit operable to measure the period of time from the transmission of the measurement request to the reception of the measurement response, as a round trip time; and

a determination unit operable to determine that the request source is an eligible device as a transmission destination of the content data, after the measurement of the round trip time, in the case where it is confirmed that;

the round trip time is less than or equal to a reference value;

the measurement response is verified as a correct response; and

the measurement request is verified as a correct request by the request source.

2. The communication apparatus according to claim 1, further comprising

a measurement preparation request transmitting unit operable to transmit, to the request source, a measurement preparation request for a preparation necessary for generating the measurement response, before the transmission of the measurement request.

3. The communication apparatus according to claim 2,

wherein said determination unit is operable to determine that the measurement response is a correct response, in the case where first verification information generated using the authentication information is identical to second verification information generated using the authentication information by the request source.

4. The communication apparatus according to claim 3,

wherein the authentication information includes a flag and certification information for the flag, the flag specifying whether or not the request source has a function of measuring a round trip time,

said communication apparatus further comprises

a measurement function determination unit operable to determine whether or not the request source has the function of measuring a round trip time, based on the flag,

wherein said measurement preparation request transmitting unit is operable to transmit the measurement preparation request in the case where the request source has the function, and not to transmit the measurement preparation request in the case where the request source does not have the function.

5. The communication apparatus according to claim 3, further comprising:

a registration unit operable to register, on a list, device identification information for identifying the request source, in the case where the request source is an eligible device as the transmission destination of the content data; and

a registration confirmation unit operable to confirm whether or not the device identification information has been registered on the list, before the measurement preparation request is transmitted to the request source,

wherein said measurement preparation request transmitting unit is operable not to transmit the measurement preparation request in the case where the device identification information has been registered on the list, and to transmit the measurement preparation request in the case where the device identification information has not been registered on the list.

6. The communication apparatus according to claim 5, further comprising

a registration canceling unit operable to cancel the registration of the device identification information when a registration effective period set in the device identification information expires.

7. The communication apparatus according to claim 3, further comprising,

in the case where the request source generates, as the preparation, request source information using the authentication information which is shared with the request source, and generates first request source partial information and second request source partial information by dividing the request source information, during the period of time from a reception of the measurement preparation request to a reception of the measurement request:

a measurement preparation unit operable to generate request destination information which corresponds to the request source information, using the authentication information, and to generate first request destination partial information and second request destination partial information by dividing the request destination information; and

a request source determination unit operable to determine that a transmission source of the measurement response is a correct request source, in the case where the second request source partial information is identical to the first request destination partial information,

wherein said measurement response receiving unit is operable to receive, from the request source, a response including the second request source partial information, as the measurement response.

8. The communication apparatus according to claim 7,

wherein in the case where the request source determines that a transmission source of the measurement request is a correct request destination, and generates the second verification information, in the case where the second request destination partial information is identical to the first request source partial information,

said determination unit includes:

a verification request transmitting unit operable to transmit, to the request source, a verification request for verifying whether or not the transmission source of the measurement request is a correct request destination; and

a verification response receiving unit operable to receive, from the request source, a verification response including the second verification information as a response to the verification request, and

said measurement request transmitting unit is operable to transmit, to the request source, a request including the second request destination partial information, as the measurement request.

9. The communication apparatus according to claim 6, further comprising:

a measurement start determination unit operable to determine whether or not to start measuring the round trip time, based on a remaining time until the registration of the device identification information is cancelled;

a measurement start request transmitting unit operable to transmit a measurement start request to the request source, in the case where the remaining time is less than or equal to a predetermined time; and

a measurement start response receiving unit operable to receive, from the request source, a measurement start response as a response to the measurement start request,

wherein said authentication unit is operable to share the authentication information with the request source, after the reception of the measurement start response from the request source.

10. The communication apparatus according to claim 1, further comprising:

a measurement start determination unit operable to determine whether or not to start measuring the round trip time;

a measurement start request transmitting unit operable to transmit, to the request source, a measurement start request which notifies a start of measuring the round trip time, in the case where the measurement of the round trip time is started; and

a measurement start response receiving unit operable to receive, from the request source, a measurement start response as a response to the measurement start request,

wherein said authentication unit is operable to share the authentication information with the request source, after the reception of the measurement start response from the request source.

11. The communication apparatus according to claim 1, further comprising:

a measurement start request receiving unit operable to receive, from the request source, a measurement start request for starting a measurement of the round trip time; and

a measurement start response transmitting unit operable to transmit, to the request source, a measurement start response as a response to the measurement start request,

wherein said authentication unit is operable to share the authentication information with the request source after the transmission of the measurement start response to the request source.

20. A communication system which comprises said communication apparatus according to claim 1 and said communication apparatus according to claim 12 that are connected to each other via a data communication network.

12. A communication apparatus which requests for transmission of content data, said apparatus comprising:

an authentication unit operable to share authentication information with a request destination which responds to the request for the transmission of the content data;

a measurement request receiving unit operable to receive, from the request destination, a measurement request which is generated using the authentication information by the request destination;

a measurement response transmitting unit operable to transmit a measurement response which is generated using the authentication information immediately back to the request destination as a response to the measurement request; and

a determination unit operable to determine whether or not the measurement request is correct.

13. The communication apparatus according to claim 12, further comprising

a measurement preparation request receiving unit operable to receive, from the request destination, a measurement preparation request for a preparation which is necessary for generating the measurement response, before the reception of the measurement request.

14. The communication apparatus according to claim 13, further comprising,

in the case where the request destination generates request destination information using the authentication information which is shared with the request source, and generates first request destination partial information and second request destination partial information by dividing the request destination information:

a measurement preparation unit operable to generate, as the preparation, request source information which corresponds to the request destination information using the authentication information, and to generate first request source partial information and second request source partial information by dividing the request source information, during the period of time from a reception of the measurement preparation request to the reception of the measurement request;

a verification request receiving unit operable to receive, from the request destination, a verification request for verifying whether or not a transmission source of the measurement request is a correct request destination;

a request destination determination unit operable to determine that the transmission source of the measurement request is the correct request destination, in the case where the second request destination partial information is identical to the first request source partial information;

a verification information generation unit operable to generate verification information which notifies that the round trip time has been measured between said communication apparatus and the request destination, using the authentication information, in the case where the transmission source of the measurement request is the correct request destination; and

a verification response transmitting unit operable to transmit, to the request destination, a verification response including the verification information, as a response to the verification request, and

wherein said measurement request receiving unit is operable to receive, from the request destination, a request including the second request destination partial information, as the measurement request.

15. The communication apparatus according to claim 14,

wherein in the case where the request destination determines that the transmission source of the measurement response is the correct request source, in the case where the second request source partial information is identical to the first request source partial information,

said measurement response transmitting unit is operable to transmit, to the request destination, a response including the second request source partial information, as the measurement response.

16. The communication apparatus according to claim 12, further comprising:

a measurement start determination unit operable to determine whether or not to start measuring the round trip time;

a measurement start request transmitting unit operable to transmit, to the request destination, a measurement start request for starting the measurement of the round trip time, in the case where the measurement of the round trip time is started; and

a measurement start response receiving unit operable to receive, from the request destination, a measurement start response as a response to the measurement start request,

wherein said authentication unit is operable to share the authentication information with the request destination, after the reception of the measurement start response from the request destination.

17. The communication apparatus according to claim 16, wherein said measurement start determination unit is operable to determine whether or not the content data has already been received, and

said measurement start request transmitting unit is operable to transmit the measurement start request to the request destination, in the case where the content data has already been received.

18. The communication apparatus according to claim 16, further comprising

a key exchange unit operable to exchange a key used for the transmission of the content data,

wherein said measurement start determination unit is operable to determine whether or not the round trip time has been measured during the period of time from when the authentication occurs to when the key exchange occurs, and

said measurement start request transmitting unit is operable to transmit the measurement start request to the request destination after the key exchange, in the case where the round trip time has not been measured.

19. The communication apparatus according to claim 12, further comprising:

a measurement start request receiving unit operable to receive, from the request destination, a measurement start request which notifies to start measuring the round trip time; and

a measurement start response transmitting unit operable to transmit, to the request destination, a measurement start response as a response to the measurement start request,

wherein said authentication unit is operable to share the authentication information with the request destination after the transmission of the measurement start response to the request destination.

21. A communication method for controlling communication between a communication apparatus of a request destination which responds to a request for transmission of content data and a communication apparatus of a request source which requests to transmit the content data, said method comprising:

a request destination authentication step, executed by the request destination, of sharing authentication information with the request source;

a request source authentication step, executed by the request source, of sharing the authentication information with the request destination;

a measurement request transmitting step, executed by the request destination, of transmitting, to the request source, a measurement request which is generated using the authentication information;

a measurement request receiving step, executed by the request source, of receiving, from the request destination, a measurement request which is generated using the authentication information by the request destination;

a measurement response transmitting step, executed by the request source, of transmitting the measurement response which is generated using the authentication information immediately back to the request destination, as a response to the measurement request;

a measurement response receiving step, executed by the request destination, of receiving, from the request source, the measurement response which is generated using the authentication information by the request source, as a response to the measurement request;

a round trip time measurement unit, executed by the request destination, of measuring the period of time from the transmission of the measurement request to the reception of the measurement response as a round trip time;

a measurement preparation request transmitting step, executed by the request destination, of transmitting, to the request source, a measurement preparation request for a preparation which is necessary for generating the measurement response, before the transmission of the measurement request;

a measurement preparation request receiving step, executed by the request source, of receiving, from the request destination, the measurement preparation request for the preparation which is necessary for generating the measurement response, before the reception of the measurement request; and

a determination step, executed by the request destination, of determining that the request source is an eligible device as a transmission destination of the content data after the measurement of the round trip time, in the case where it is confirmed that;

the round trip time is less than or equal to a reference value;

the measurement response is verified as a correct response; and

the measurement request is verified as a correct request by the request source.

22. A communication program for controlling a communication apparatus which responds to a request for transmission of content data, said program causing a computer system to execute:

an authentication step of sharing authentication information with a request source which requests for the transmission of the content data;

a measurement request transmitting step of transmitting, to the request source, a measurement request which is generated using the authentication information;

a measurement response receiving step of receiving, from the request source, a measurement response which is generated using the authentication information by the request source, as a response to the measurement request;

a round trip time measurement step of measuring the period of time from the transmission of the measurement request to the reception of the measurement response, as a round trip time;

a measurement preparation request transmitting step of transmitting, to the request source, a measurement preparation request for a preparation which is necessary for generating the measurement response, before the transmission of the measurement request; and

a determination step of determining that the request source is an eligible device as a transmission destination of the content data, after the measurement of the round trip time, in the case where it is confirmed that the round trip time is less than or equal to a reference value;

the measurement response is verified as a correct response; and

the measurement request is verified as a correct request by the request source.

24. A computer-readable recording medium on which the communication program according to claim 22 is recorded.

23. A communication program for controlling a communication apparatus which requests for transmission of content data, said program causing a computer system to execute:

an authentication step of sharing authentication information with a request destination which responds to the request for the transmission of the content data;

a measurement request receiving step of receiving, from the request destination, a measurement request which is generated using the authentication information by the request destination;

a measurement response transmitting step of transmitting the measurement response which is generated using the authentication information immediately back to the request destination, as a response to the measurement request;

a measurement preparation request receiving step of receiving, from the request destination, a measurement preparation request for a preparation which is necessary for generating the measurement response, before the reception of the measurement request; and

a determination step of determining whether or not the measurement request is correct.

25. A computer-readable recording medium on which the communication program according to claim 23 is recorded.