Communication apparatus and a communication system

• US 6,078,663 A
• Filed: 06/26/1996
• Issued: 06/20/2000
• Est. Priority Date: 06/30/1995
• Status: Expired due to Term

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yamamoto, Takahisa
• Primary Examiner(s): Oen, William
• Assistant Examiner(s): CLARK, ROBIN C
• Application Number:
  US08/670,608
• Time in Patent Office: 1,455 Days
• Field of Search: 380/1, 380/4, 380/21, 380/28, 380/29, 380/30, 380/37, 380/42, 380/44, 380/45, 380/47, 380/48, 380/59, 380/46
• US Class Current: 380/260
• CPC Class Codes: H04L 2209/60 Digital content management, e.g. content distribution
• CPC Class Codes: H04L 9/0637 Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM]
• CPC Class Codes: H04L 9/0662 with particular pseudorandom sequence generator
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying

Abstract

A communication device according to the present invention comprises an enciphering transmitter for enciphering data and transmitting enciphered data, a counter for obtaining a count of a quantity of enciphered data, and an accounting circuit for calculating, in accordance with the count held by the counter, an amount to charge a user for the data.

Claims

1. A cryptographic communication device comprising:

cryptographic communication means for enciphering transmission data and deciphering received enciphered data and for performing communication;

changing means for changing a rate that is applied for enciphering/deciphering data; and

accounting means for charging in accordance with the changed rate for enciphering/deciphering data.

2. A cryptographic communication device according to claim 1, wherein said cryptographic communication means includes:

an encipherer for performing enciphering according to a specific algorithm;

a pseudo-random number generator for performing predetermined calculations to generate a pseudo-random number sequence; and

a computing unit for converting, into a series of keys for said encipherer, said pseudo-random number sequence that is output by said pseudo-random number generator, and wherein a cryptographic key for said encipherer is updated by using said series of keys that is generated by said computing unit, and said change means changes a processing rate for said encipherer and/or a generation rate for said pseudo-random number generator.

3. A cryptographic communication device according to claim 2, wherein a square-type pseudo-random number sequence that is secure from a calculation amount is employed as said pseudo-random number sequence that is generated by said pseudo-random number generator.

4. A cryptographic communication device according to claim 3, wherein a square-type pseudo-random number generator is employed as said pseudo-random number generator.

5. A cryptographic communication device according to claim 1, wherein said change means employs clock selection means for selecting an arbitrary clock from among a plurality of clocks that have different frequencies.

6. A cryptographic communication device according to claim 2, wherein said change means employs a plurality of processing means for performing a repetitive portion of processing that is performed by said encipherer and/or said pseudo-random number generator.

7. A cryptographic communication device according to claim 1, wherein said cryptographic communication means has inherent and secret common keys and includes an encipherer for performing enciphering and deciphering according to a predetermined algorithm.

8. An enciphering device comprising:

enciphering means for enciphering and deciphering a predetermined algorithm;

changing means for changing a rate for said enciphering means without changing said predetermined algorithm; and

accounting means for charging in accordance with the changed rate for enciphering/deciphering data.

9. An enciphering device comprising:

enciphering means capable of changing an enciphering power;

changing means for changing said encipher power of said enciphering means in accordance with a deciphering capability of a transmission destination; and

accounting means for charging in accordance with the changed encipher power.

10. An enciphering device comprising:

enciphering means capable of changing an encipher power;

changing means for changing said encipher power of said enciphering means by negotiation with a transmission destination; and

accounting means for charging in accordance with the changed encipher power.

11. An cryptographic communication device comprising:

(a) encipher transmission means for enciphering data and transmitting enciphered data;

(b) selection means for selecting an enciphering rate for said encipher transmission means; and

(c) accounting means for charging a user for said enciphered data in accordance with said enciphering rate that is selected by said selection means.

12. A cryptographic communication device according to claim 11, wherein said cryptographic communication means has inherent and secret common keys for said cryptographic communication means and receiving and deciphering means on a reception side, and includes:

an encipherer for performing enciphering according to a specific algorithm;

a pseudo-random number generator for performing predetermined calculations to generate a pseudo-random number sequence; and

a computing unit for converting, into a series of keys for said encipherer, said pseudo-random number sequence that is output by said pseudo-random number generator, and wherein said selection means selects said enciphering rate and/or a generation rate for said pseudo-random number sequence, and said accounting means calculates a charge in accordance with said enciphering rate and/or said generation rate selected by said selection means.

13. A cryptographic communication device according to claim 12, wherein a square-type pseudo-random number sequence that is secure from a calculation amount is employed as said pseudo-random number sequence that is generated by said pseudo-random number generator.

14. A cryptographic communication device according to claim 12, wherein a square-type pseudo-random number generator is employed as said pseudo-random number generator.

15. A cryptographic communication device according to claim 11, wherein employed as said selection means is clock selection means for selecting an arbitrary clock from among a plurality of clocks having different frequencies.

16. A cryptographic communication device according to claim 12, further comprising a plurality of processing means for performing a repeated portion of a process performed by said encipherer and/or said pseudo-random number generator, wherein said selection means determines a number of said plurality of processing means to be used.

17. A cryptographic communication device according to claim 12, further comprising processing means for performing a repeated portion of a process performed by said encipherer and/or said pseudo-random number generator, wherein said selection means determines how many times said processing means is to be used.

18. A cryptographic communication method, whereby enciphered data are transmitted across a network and setting of variable enciphering power is possible, comprising a step whereat said data transmission side charges a data reception side in consonance with said enciphering power.

19. A method comprising the steps of:

setting an encipher power to one of a plurality of values; and

charging in accordance with the set encipher power.

20. A method according to claim 19, wherein said encipher power is set in accordance with a deciphering capability of a transmission destination.

21. A method according to claim 19, wherein said encipher power is set in accordance with a negotiation with a transmission destination.

22. A computer readable memory for storing a program having the steps of:

setting an encipher power to one of a plurality of values; and

charging in accordance with the set encipher power.

23. An information providing system comprising:

an information provider comprising;

a data base,

encipher transmission means for enciphering data stored in said data base,

setting means for setting a mode of said encipher transmission means, and

accounting means for charging for the enciphered data based on the set mode; and

a terminal device, connected with said information provider via a network, having deciphering means for deciphering the data enciphered by said information provider.

24. A system according to claim 23, wherein said setting means sets an encipher power for the set mode.

25. A system according to claim 23, wherein said setting means sets an enciphering rate for the set mode.