US 6,009,177 A · Enhanced cryptographic system and method with key escrow feature

Abstract

The invention provides a cryptographic system and method with a key escrow feature that uses a method for verifiably splitting users' private encryption keys into components and for sending those components to trusted agents chosen by the particular users, and provides a system that uses modern public key certificate management, enforced by a chip device that also self-certifies. The methods for key escrow and receiving an escrow certificate are also applied herein to a more generalized case of registering a trusted device with a trusted third party and receiving authorization from that party enabling the device to communicate with other trusted devices. Further preferred embodiments provide for rekeying and upgrading of device firmware using a certificate system, and encryption of stream-oriented data.

Claims18

Dependent claims

A method of upgrading firmware of a trusted device, comprising the steps of:

receiving a communication of firmware at a trusted device;
confirming the source of said communication using a key embedded in said trusted device, said key being a key associated with a firmware source;
and
incorporating the firmware into the trusted device contingent upon the firmware source being confirmed;
wherein the key embedded in the trusted device is a public signature verification key of a trusted entity and wherein said confirming step includes a step of:
verifying, using the public signature verification key of the trusted entity, that the communication includes an upgrade certificate signed using a private signature key of the trusted entity;
and
wherein the upgrade certificate includes a public signature key of the firmware source.

5 more elements

Dependencies are inferred from the claim text.

Enhanced cryptographic system and method with key escrow feature

Life of this patent

Enhanced cryptographic system and method with key escrow feature

Life of this patent

Abstract

Claims18