Patent · US Expired

System for controlling access to encrypted data files by a plurality of users

US6178508A · kind A · utility

66Cited by
15References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 26, 1998
Grant dateJan 23, 2001
Priority date
Expiry dateFeb 26, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2221/2107
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A system in which an encrypted data file can be protected, accessed, and maintained by a plurality of users using cryptographically hashed passwords. The system provides for the creation in memory for each authorized user of a cryptographically hashed password as an entry in an unencrypted header file. The system compares an authorized user's cryptographically hashed password against a corresponding set of cryptographically hashed passwords in memory to determine whether the user is allowed access to the protected data file. The passwords are cryptographically one-way hashed with a "salt" value in such a way as to make reconstruction of original passwords by an unintended party virtually impossible, because the passwords never exist in memory in an unhashed state. Furthermore, the passwords are cryptographically "one-way" hashed so as not to be reconstructible. Upon successful authorization of a user, based on successful comparison of the user's hashed password with those in memory, the user gains access to the encrypted data file.

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