Filing Information

Inventor(s)	J rgen Bjerrum · Steen Ottosen · Kj r; Nielsen; Sven ·
Assignee(s)	Kommunedata I/S ·  View assignee updates
Attorney/Agent(s)	Merchant & Gould, Smith, Edell, Welter & Schmidt ·
Primary Examiner	Salvatore Cangialosi ·
Application Number	US7772372
Filing date	11/05/1991
PCT 371 date	11/05/1991
Issue date	05/10/1994
Predicted expiration date	11/05/2011
U.S. Classifications	380/25  · 380/23  ·
International Classifications	H04C 912  ·
Kind Code	A
International Classifications	38023;25 ·
PCT Application Number	PCTDK9000141 - 06/07/1990
PCT Publication Number	WO199015490 - 12/13/1990
Foreign Priority	DK279089 - 06/07/1989 ·

Patent Family

Abstract

When transferring data, an electronic document or the like from a first computer system (100) to a second computer system (200) via a data transmission line (300), e.g. a public data transmission line, a first output and input station (122) comprising a first electronic card (124) and a second output and input station (222) comprising a second electronic card (224) are used. The data is transferred to the first electronic card (124) from the first computer system (100) via the first station (122) and is encrypted in the first electronic card (124), whereupon the data is output from the first electronic card (124) in encrypted form and transferred via the first station (122) to the first computer system (100) and therefrom to the data transmission line (300). The data is received by the other computer system (200) in encrypted form and is transferred to the second electronic card (224) via the second station (222), whereupon the data is decrypted in the second electronic card (224) and is output from the second electronic card via the second station (222) to the second computer system (200). As the data transfer between the first and the second computer system is carried out between the first and the second electronic card, no third parties have neither authorized or unauthorized possibility of interfering with the data transmission and possibly changing the data or the electronic document. The first and second electronic card (124, 224) constitute a coherent set of cards comprising coherent encryption/decryption keys input into the internal storages of the cards.

Independent Claims | See all claims (33)

1. 1. A method of transferring data from a first computer system to a second computer system via a data transmission line by use of a coherent set of electronic cards, wherein for said transfera first station is used for outputting data from and inputting data into a first electronic card, said first station being connected to and communicating with said first computer system and furthermore being connected to said data transmission line via said first computer system and interfacing means, anda second station is used for outputting data from and inputting data into a second electronic card, said second station being connected to and communicating with said second computer system and furthermore being connected to said data transmission line via this second computer system and interfacing means,said first and second electronic card each comprising a central data processing unit, an internal storage means, an input/output gate for communication with said corresponding station as well as an encryption/decryption means and together constituting the coherent set of electronic cards comprising coherent encryption and decryption keys input into said internal storages of said cards in such a way that the cards are able to communicate with each other and encrypt and decrypt data transferred from the first card to the second card and vice versa, said method comprising the steps of:transferring said data to said first electronic card from said first computer system via said first station and said input/output gate of said first electronic card, and inputting and temporarily storing said data in said internal storage of said first electronic card,outputting said data from said internal storage of said first electronic card and encrypting said data in said first electronic card by means of said encryption/decryption means of said first electronic card and said encryption key(s) stored in said internal storage of said first electronic card,outputting said data from said first electronic card in encrypted form via said input/output gate of said first electronic card and transferring said encrypted data via said first station to said first computer system and therefrom via said interfacing means of said first computer system to said data transmission line,receiving said data by said second computer system in encrypted form via said interfacing means of said second computer system, transferring said encrypted data to said second electronic card via said second station and via said input/output gate of said second electronic card, and inputting and temporarily storing said data in said internal storage of said second electronic card,outputting said data from said internal storage of said second electronic card in encrypted form and decrypting said data in said second electronic card by means of said encryption/decryption means of said second electronic card and said decryption key(s) stored in said internal storage of said second electronic card, andoutputting said data from said second electronic card in encrypted form via said input/output gate of said second electronic card and via said second station to said second computer system.