Communications network using an enciphering and deciphering device

• US 4,823,388 A
• Filed: 02/05/1987
• Issued: 04/18/1989
• Est. Priority Date: 06/25/1984
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Mizutani, Hiroyuki, Kamitake, Takashi
• Primary Examiner(s): CANGIALOSI, SALVATORE A
• Application Number:
  US07/014,213
• Time in Patent Office: 803 Days
• Field of Search: 380/23-25, 380/28, 380/29, 235/374-382
• US Class Current: 705/67
• CPC Class Codes: G06Q 20/085 involving remote charge determination or related payment systems
• 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
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 9/3234 involving additional secure or trusted devices, e.g. TPM, smartcard, USB or software token network architectures or network communication protocols for supporting authentication of entities using an additional device in a packet data network H04L63/0853
• CPC Class Codes: H04L 9/3247 involving digital signatures

Abstract

A communications network system is constructed by connecting a plurality of customer terminals to one central terminal via communication lines. Enciphering devices and a deciphering device, such as IC (integrated circuit) cards, are provided for the terminals. In order to achieve a digital signature for a transaction message sent from a customer to the center, the message is enciphered according to a prescribed enciphering algorithm using a key word that can specify the sender and the transaction. At the central terminal the enciphered message is deciphered according to a prescribed deciphering algorithm that is different from the enciphering algorithm using a key word which can specify the sender and the transaction. The key data and encipering and deciphering algorithms are sealed in the enciphering and deciphering devices such that they cannot be accessed from the outside.

Claims