×

Public key/signature cryptosystem with enhanced digital signature certification

  • US 5,005,200 A
  • Filed: 03/07/1989
  • Issued: 04/02/1991
  • Est. Priority Date: 02/12/1988
  • Status: Expired due to Term
First Claim
Patent Images

1. In a communication system having a plurality of terminal devices coupled to a channel over which users may exchange messages, at least some of said user'"'"'s having a public key and an associated private key, a method for controlling authority in a hierarchical manner among a group of users, comprising the steps of:

  • specifying at least first and second digital authority defining data structures, said data structures having digital values which can be associated with at least one user'"'"'s private key,said step of specifying including the step ofdigitally specifying a set of authorities from a sufficient plurality of authorities so that a first user may digitally delegate authorities to second and third users so that the authorities delegated to the second user are different than those delegated to the third user, providing that the first user'"'"'s digital authority defining data structure allows for such delegation; and

    digitally signing by the first user the second digital data structure so that signatures performed by the second user'"'"'s private key associated with the second data structure will be recognized upon an electronic analysis of the digital signature as having been granted said authority by the first user in accordance with the first user'"'"'s authority-defining data structure.

View all claims
  • 0 Assignments
Timeline View
Assignment View
    ×
    ×