Authentication method, authentication apparatus, authentication system and IC card

• US 6,484,948 B1
• Filed: 08/09/2000
• Issued: 11/26/2002
• Est. Priority Date: 03/14/2000
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Sonoda, Kenichiro
• Primary Examiner(s): Frech, Karl D.
• Assistant Examiner(s): Kim, Ahshik
• Application Number:
  US09/635,224
• Time in Patent Office: 839 Days
• Field of Search: 235/370, 235/380, 235/382, 235/440, 235/441, 235/449, 235/454
• US Class Current: 235/492
• CPC Class Codes: G06K 19/07 with integrated circuit chips
• CPC Class Codes: G06K 19/073 Special arrangements for circuits, e.g. for protecting identification code in memory protection against unauthorised use of computer memory G06F12/14
• CPC Class Codes: G06K 19/07372 by detecting tampering with the circuit
• CPC Class Codes: G06Q 20/341 Active cards, i.e. cards including their own processing means, e.g. including an IC or chip
• CPC Class Codes: G07F 7/082 Features insuring the integrity of the data on or in the card
• CPC Class Codes: G07F 7/1008 Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: H01L 2223/5444 for electrical read out
• CPC Class Codes: H01L 2223/54473 for use after dicing
• CPC Class Codes: H01L 23/544 Marks applied to semiconductor devices or parts, e.g. registration marks, alignment structures, wafer maps test patterns for characterising or monitoring manufacturing processes H01L22/00
• CPC Class Codes: H01L 23/57 Protection from inspection, reverse engineering or tampering
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00

Abstract

An authentication signal extraction part measures the frequency spectrum of electric noise specific to a semiconductor element for authentication so that a code depending on this frequency spectrum is generated as an authentication signal. An authentication signal storage part previously registers the authentication signal. When performing authentication, the authentication signal generated from the authentication signal extraction part is compared with a registered authentication signal stored in the authentication signal storage part so that a result display part displays successful authentication when coincidence is recognized. Thus, authentication is performed without forming a nonvolatile memory or writing the authentication signal.

Claims

1. An authentication apparatus comprising:

an authentication signal extraction part generating and outputting an authentication signal with respect to a detachably connected semiconductor element on the basis of its electric noise;

a storage part storing at least one registered authentication signal each comparable with said authentication signal;

a comparison part comparing said authentication signal output from said authentication signal extraction part with said at least one registered authentication signal stored in said storage part; and

a control part making said comparison part compare said authentication signal output from said authentication signal extraction part with each of said at least one registered authentication signal stored in said storage part for executing authentication processing determining coincidence in any comparison.

2. The authentication apparatus according to claim 1, wherein

said control part selectively executes said authentication processing and registration processing making said storage part store said authentication signal output from said authentication signal extraction part as one of said at least one registered authentication signal.

3. The authentication apparatus according to claim 1, wherein

said control part selectively executes said authentication processing and registration processing making said comparison part compare said authentication signal output from said authentication signal extraction part with each of said at least one registered authentication signal stored in said storage part for making said storage part store said authentication signal only when no coincidence is recognized in any comparison.

4. The authentication apparatus according to claim 1, wherein

said authentication signal extraction part measures said electric noise with respect to said semiconductor element thereby generating a code or codes depending on the frequency spectrum of said electric noise and outputting said code or codes as said authentication signal.

5. The authentication apparatus according to claim 4, wherein

said authentication signal extraction part measures, with respect to an element comprising a plurality of unit semiconductor elements as said semiconductor element, electric noise of the respective ones of said plurality of unit semiconductor elements thereby obtaining codes depending on the frequency spectra of said electric noise and outputting a set of said codes as said authentication signal.

6. The authentication apparatus according to claim 4, wherein

said authentication signal extraction part generates a set of numerical values expressing the values of said frequency spectra corresponding to a plurality of frequencies as said codes.

7. An authentication system comprising:

a terminal having an authentication signal extraction part generating and outputting an authentication signal with respect to a detachably connected semiconductor element on the basis of its electric noise; and

common carrier equipment, connected to said terminal through a communication line, having;

a storage part storing at least one registered authentication signal each comparable with said authentication signal,

a comparison part comparing said authentication signal output from said authentication signal extraction part with said at least one registered authentication signal stored in said storage part, and

a control part making said comparison part compare said authentication signal output from said authentication signal extraction part with each of said at least one registered authentication signal stored in said storage part for executing authentication processing determining coincidence in any comparison.

8. An IC card comprising:

a semiconductor device having an integrated circuit and a semiconductor element built into the same semiconductor substrate; and

a terminal group including a plurality of terminals connected to said semiconductor element for enabling connection between said semiconductor device and the exterior,

wherein said electric noise of said semiconductor element is derived from said plurality of terminals to the exterior and converted into said authentication signal.

9. The IC card according to claim 8, further comprising a switching element interposed between said semiconductor element and at least one of said plurality of terminals, wherein

said terminal group further includes a terminal relaying a signal controlling said switching element.

10. The IC card according to claim 9, wherein

said semiconductor element has at least one MOSFET.