Communication apparatus

• US 5,109,152 A
• Filed: 03/08/1990
• Issued: 04/28/1992
• Est. Priority Date: 07/13/1988
• Status: Expired due to Term

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation)
• Inventors: Itoh, Mamoru, Takagi, Nobuya
• Primary Examiner(s): Levy, Stuart S.
• Assistant Examiner(s): Rhoa, Joseph A.
• Application Number:
  US07/465,210
• Time in Patent Office: 782 Days
• Field of Search: 235/379-382, 235/492, 380/20-28, 340/825.34
• US Class Current: 235/380
• 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: G06Q 20/3674 involving authentication
• CPC Class Codes: G06Q 20/40975 using encryption therefor
• 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: G07F 7/1016 Devices or methods for securing the PIN and other transaction-data, e.g. by encryption arrangements for secret communication, see H04L9/00

Abstract

This invention is intended for the communication between a first communication device (e.g., an IC card) and a second communication device (e.g., a card terminal) by preventing the faking of the IC card or card terminal, for example, thereby allowing correct information exchange between them. The invention provides the IC card with a first encryption means and the card terminal with a second encryption means. In consequence, communication signals in both directions are encrypted, and random numbers and the algorism of functional computation are prevented from being analyzed. As a result, manufacturing of fake devices can be prevented and correct information exchange can be performed.

Claims

1. A communication apparatus having a first communication device and a second communication device which performs communication with said first communication device, said first communication device comprising first random number generation means which generates a random number, first encryption means which encrypts the random number provided by said first random number generation means, second decryption means which decrypts data entered from said second communication device, data separation means which separates data provided by said second decryption means into first data and second data, third encryption means which encrypts the second data provided by said data separation means, comparison means which compares the random number provided by said first random number generation means with the first data provided by said data separation means, first processing means which performs such data processings as data input/output, storing and operation, and first communication means which processes data provided by said first processing means by using the second data provided by said data separation means and the random number provided by said first random number generation means and thereafter sends it to said second communication device, or receives and processes the data entered from said second communication device by using the second data provided by said data separation means and random number provided by said random number generation means and thereafter delivers it to said first processing means, said second communication device comprising second random number generation means which generates a random number, first decryption means which decrypts encrypted data entered from said first communication device, data linkage means which links the random number provided by said second random number generation means and data provided by said first decryption means, second encryption means which encrypts liked data provided by said data linkage means, third decryption means which decrypts encrypted data entered from said first communication device, a second comparison means which compares the random number provided by said second random number generation means with data provided by said third decryption means, second processing means which performs such data processings as data input/output, storing and operation, and second communication means which processes data provided by said second processing means by using the data provided by said first decryption means and the random number provided by said second random number generation means and thereafter sends it to said first communication device, or receives and processes data entered from said first communication device by using the data provided by said first decryption means and the random number provided by said second random number generation means and thereafter delivers it to said second processing means.

2. A communication apparatus according to claim 1, wherein said random number generation means comprises long-period data generation means which sequentially produces data strings having a long period, a piece of data at a time, and randomizing means which randomizes the output of said long-period data generation means based on a key which is a value native to the first communication device.

3. A communication apparatus according to claim 2, wherein said long-period data generation means comprises nonvolatile storage means.

4. A communication apparatus according to claim 2, wherein at least two means out of the randomizing means, first encryption means, second encryption means and third encryption means comprise same computation means.

5. A communication apparatus according to claim 1, wherein the first communication device or second communication device is an IC card.

6. A communication apparatus having a first communication device and a second communication device which performs communication with said first communication device, said first communication device comprising first encryption means which enters an n-bit plain text and produces an n-bit cipher text, a first register, and first exclusive-OR operation means, said second communication device comprising decryption means which pairs with said first encryption means, a second register, second exclusive-OR operation means, second encryption means which implements a same operation as of said first encryption means, a third register, third exclusive-OR operation means, and comparison means, said first exclusive-OR operation means implementing the exclusive-OR operation for one of a plurality of n-bit data provided by dividing in n-bit units a plain text block and the contents of said first register and delivers it to said first encryption means, said first encryption means implementing a confidential operation for said output from said first exclusive-OR operation means and delivers it to said decryption means, said decryption means implementing a confidential operation for the output from said first encryption means and delivers it to said second exclusive-OR operation means, said second exclusive-OR operation means implementing the exclusive-OR operation for the output from said decryption means and the contents of said second register thereby to produce n-bit restored data, said third exclusive-OR operation means implementing the exclusive-OR operation for said n-bit restored data and the contents of said third register and delivers it to said second encryption means, said second encryption means implementing an operation for the output from said third exclusive-OR operation means.

7. A communication apparatus according to claim 6, wherein the first communication device or second communication device is an IC card.

8. A communication apparatus having a first communication device and a second communication device which performs communication with said first communication device, said first communication device comprising encryption means which enters an n-bit plain text and produces an n-bit cipher text, a first register, a second register, a first exclusive-OR operation means, and a second exclusive-OR operation means, said second communication device comprising decryption means which pairs with said encryption means, a third register, a fourth register, third exclusive-OR operation means, fourth exclusive-OR operation means, and comparison means, said first exclusive-OR operation means implementing the exclusive-OR operation for one of a plurality of n-bit data provided by dividing in n-bit units a plain text block and the contents of said first register and delivers it to said encryption means, said encryption means implementing a confidential operation for the output from said first exclusive-OR operation means and delivers it to said second exclusive-OR operation means, said second exclusive-OR operation means implementing the exclusive-OR operation for the output from said encryption means and the contents of said second register and delivers it to said third exclusive-OR operation means, said third exclusive-OR operation means implementing the exclusive-OR operation for the output from said second exclusive-OR operation means and the contents of said third register and delivers it to said decryption means, said decryption means implementing a confidential operation for the output from said third exclusive-OR operation means and delivers it to said fourth exclusive-OR operation means, said fourth exclusive-OR operation means implementing the exclusive-OR operation for the output from said decryption means and the contents of said fourth register.

9. A communication apparatus according to claim 8, wherein the first communication device or second communication device is an IC card.