Patent · US Expired

Auto-recoverable and auto-certifiable cryptosystem with unescrowed signing keys

US6122742A · kind A · utility

18Cited by
22References
20Claims
0Family size

Inventors

Key dates

Filing dateJun 18, 1997
Grant dateSep 19, 2000
Priority date
Expiry dateJun 18, 2017

Classification

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

Abstract

A method is provided for an escrow cryptosystem combined with an unescrowed digital signature scheme that uses a single public key per user. This system is overhead-free, does not require a cryptographic tamper-proof hardware implementation (i.e., can be done in software), and is publicly verifiable. The system cannot be used subliminally to enable a shadow public key system. Namely, an unescrowed public key system that is publicly displayed in a covert fashion. The cryptosystem contains a key generation mechanism that outputs a key triplet, and a certificate of proof that the keys were generated according to the algorithm. The key triplet consists of a public key, a private decryption key, and a private signing key. Using the public key and the certificate, the triplet can be verified efficiently by anyone to have the following properties: (1) the private signing key is known to the user, and (2) the private decryption key is recoverable by the escrow authorities. The system assures that the escrow authorities are not able to forge signatures or get the private signing key. The system is designed so that its internals can be made publicly scrutinizable (e.g., it can be distributed…

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