Cryptographic system and method with key escrow feature

摘要

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. In a preferred embodiment of this invention, the chip encrypts or decrypts only if certain conditions are met, namely, (1) if a valid "sender certificate" and a valid "recipient certificate" are input, where "valid" means that the particular user's private decryption key is provably escrowed with a specified number of escrow agents and that the master escrow center is registered and certified by the chip manufacturer, and (2) if a valid Message Control Header is generated by the sender and validated by the recipient, thereby giving authorized investigators sufficient information with which to request and obtain the escrowed keys.