Patent · US Expired

Communications line authentication device

US4159468A · kind A · utility

129Cited by
7References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 17, 1977
Grant dateJun 26, 1979
Priority date
Expiry dateNov 17, 1997

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY04S40/20
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A device for insertion in a communications line for verifying message integrity within a significant portion of existing communications networks. At the transmitter end, the device receives plain text messages from the communications line, generates an authentication field by encrypting the plain text message received and retransmits the plain test message received, with the authentication field appended thereto, onto the communications line. At the receiver end, the device receives messages from the communications line, generates an authentication field by encrypting the plain text portion of the message received and compares the authentication field generated with the authentication field appended to the plain text portion of the message received. If the two authentication fields are identical, the plain text message has been received exactly as it was transmitted, and the receiving device will transmit the plain text portion of the message received to the receiving terminal, appending thereto a character indicating message integrity. Similarly, if the two authentication fields differ, the receiving device will transmit to the receiving terminal the plain text portion of the mess…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.