Patent · US Expired

System and method for access field verification

US5956403A · kind A · utility

66Cited by
43References
53Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 16, 1997
Grant dateSep 21, 1999
Priority date
Expiry dateJun 16, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L9/0894
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A system and method for key escrow cryptography for use in a system comprising a sender and a receiver. Only public escrow keys are stored in the sender and the receiver. The sender encrypts a message using a secret session key (KS), and generates a leaf verification string (LVS) by combining an unique program identifier (UIP), a public portion of a program unique key (KUpub), and a signature. The sender encrypts the KS using the KUpub to generate a first encrypted session key (EKS), and generates a first law enforcement access field (LEAF) by encrypting a combination of the first EKS and the UIP with a copy of a public portion of a family key (KFpub) stored in the sender. The encrypted message, the LVS, and the first LEAF are transmitted from the sender to the receiver. The receiver stores therein a public portion of the KEPF key (KEPFpub). The receiver extracts the UIP, KUpub, and the signature from the LVS, and then encrypts the KS using the extracted KUpub to generate a second encrypted session key (EKS). The receiver generates a second LEAF by encrypting a combination of the second EKS and the extracted UIP with a copy of the KFpub stored in the receiver. The receiver then com…

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