| 6167521 |
Securely downloading and executing code from mutually suspicious authorities |
| Dec-26-2000 |
An apparatus, system and method for secure code-downloading and information exchange, in the full generality of complex code dependencies while considering the implications of mutual distrust and hot-swapping.... |
| 6160891 |
Methods and apparatus for recovering keys |
| Dec-12-2000 |
A key such as a private key or key password of a private key is encrypted for storage, and may be decrypted if the private key becomes lost or unavailable. The key is encrypted by encoding, for example,... |
| 6151395 |
System and method for regenerating secret keys in diffie-hellman communication sessions |
| Nov-21-2000 |
The present invention is directed to a system and method for regenerating secret keys by escrowing only one private value in a Diffie-Hellman exchange where a public number is exchanged between the two... |
| 6141423 |
Method for preventing inadvertent betrayal by a trustee of escrowed digital secrets |
| Oct-31-2000 |
The invention employs a voluntary identification/definition phase performed, for example, shortly after a computer is purchased, and a secret information retrieval phase. In the definition phase, the true... |
| 6118874 |
Encrypted data recovery method using split storage key and system thereof |
| Sep-12-2000 |
When a secret is encrypted and stored, it is necessary to provide a countermeasure for the situation where a key is lost (key recovery system). In the present invention, a key recovery system for an enveloped... |
| 6088454 |
Key management method, encryption system, and sharing digital signature system which have hierarchies |
| Jul-11-2000 |
A key management method, an encryption system, and a sharing digital signature system are provided, which are designed to hierarchically manage the degrees of contribution of members to a digital signature... |
| 6072876 |
Method and system for depositing private key used in RSA cryptosystem |
| Jun-6-2000 |
A scheme for depositing a private key used in the RSA cryptosystem which is capable of maintaining the private key more safely, without requiring a user to always carry around a storage medium. In this... |
| 6058188 |
Method and apparatus for interoperable validation of key recovery information in a cryptographic system |
| May-2-2000 |
In a cryptographic communications system, a method and apparatus for allowing a sender of encrypted data to demonstrate to a receiver its ability to correctly generate key recovery information that is... |
| 6052469 |
Interoperable cryptographic key recovery system with verification by comparison |
| Apr-18-2000 |
A cryptographic key recovery system that is interoperable with existing systems for establishing keys between communicating parties. The sender uses a reversible key inversion function to generate key... |
| 6044155 |
Method and system for securely archiving core data secrets |
| Mar-28-2000 |
The invention provides central storage for core data secrets, referred to as data items. The data items are encrypted by a client computer using a client key that is derived from a logon secret, such as... |
| 6035041 |
Optimal-resilience, proactive, public-key cryptographic system and method |
| Mar-7-2000 |
Proactive robust threshold schemes are presented for general "homomorphic-type" public key systems, as well as optimized systems for the RSA function. Proactive security employs dynamic memory refreshing... |
| 6026163 |
Distributed split-key cryptosystem and applications |
| Feb-15-2000 |
A distributed split-key cryptosystem and application in a public-key setting wherein each of a plurality of trustees independently selects his own secret-public key pair. The trustees combine their public... |
| 5991406 |
System and method for data recovery |
| Nov-23-1999 |
A system and method for data escrow cryptography are described. An encrypting user encrypts a message using a secret storage key (KS) and attaches a data recovery field (DRF), including an access rule... |
| 5968177 |
Method and apparatus for processing administration of a secured community |
| Oct-19-1999 |
A method and apparatus for processing administration in a secure community, or communication system, is accomplished by dividing the single computing devices functionality of the administrator/officer/server... |
| 5956403 |
System and method for access field verification |
| Sep-21-1999 |
A system and method for key escrow cryptography for use in a system comprising a sender and a receiver. Only public escrow keys are stored in the sender and the receiver. The sender encrypts a message... |
| 5937066 |
Two-phase cryptographic key recovery system |
| Aug-10-1999 |
A cryptographic key recovery system that operates in two phases. In the first phase, the sender establishes a secret value with the receiver. For each key recovery agent, the sender generates a key-generating... |
| 5937067 |
Apparatus and method for local encryption control of a global transport data stream |
| Aug-10-1999 |
An encryption control system to process an input transport data stream into an output transport data stream includes an input demultiplexer, a first secure microprocessor, a second secure microprocessor... |
| 5920630 |
Method of public key cryptography that includes key escrow |
| Jul-6-1999 |
A key escrow encryption method, where two users each have secret encryption keys and corresponding public encryption keys. One user receives the public encryption keys of the other user and generates a... |
| 5917911 |
Method and system for hierarchical key access and recovery |
| Jun-29-1999 |
A key management system includes a hierarchy (10) of independent key arbitration centers (KAC) for providing access to a user's session keys through key management centers (KMC). When a court order is... |
| 5907618 |
Method and apparatus for verifiably providing key recovery information in a cryptographic system |
| May-25-1999 |
A method and apparatus for verifiably providing key recovery information to one or more trustees in a cryptographic communication system having a sender and a receiver Each communicating party has its... |
| 5901227 |
Method and apparatus for implementing partial and complete optional key escrow |
| May-4-1999 |
A key escrow technique reliably notifies an encrypting principal about escrow authorities requiring access to a secret key used to encrypt information and, further, about how much of that key is required... |
| 5872849 |
Enhanced cryptographic system and method with key escrow feature |
| Feb-16-1999 |
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... |
| 5867578 |
Adaptive multi-step digital signature system and method of operation thereof |
| Feb-2-1999 |
A multi-step digital signature system and method is provided having a distributed root certifying authority 20. Messages received at the root certifying authority 20 are distributed to root certifying... |
| 5857022 |
Enhanced cryptographic system and method with key escrow feature |
| Jan-5-1999 |
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... |
| 5857025 |
Electronic encryption device and method |
| Jan-5-1999 |
A device and method is provided using a split processor based architecture to provide physical security of critical information by implementing a required protocol before releasing critical information.... |
| 5852665 |
Internationally regulated system for one to one cryptographic communications with national sovereignty without key escrow |
| Dec-22-1998 |
This invention discloses an encryption method for generating an encrypted message which is controllably decryptable, the method including providing at least one agency public key to at least one decrypting... |
| 5850451 |
Enhanced cryptographic system and method with key escrow feature |
| Dec-15-1998 |
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... |
| 5841865 |
Enhanced cryptographic system and method with key escrow feature |
| Nov-24-1998 |
The invention provides a cryptographic system and method with a key escrow feature that uses a method for verifiably splitting users' private keys into components and for sending those components to trusted... |
| 5835596 |
International cryptography framework |
| Nov-10-1998 |
A cryptographic framework consists of four basic service elements that include a national flag card, a cryptographic unit, a host system, and a network security server. Three of the four service elements... |
| 5825880 |
Multi-step digital signature method and system |
| Oct-20-1998 |
A multi-step signing system and method uses multiple signing devices to affix a single signature which can be verified using a single public verification key. Each signing device possesses a share of the... |
| 5815573 |
Cryptographic key recovery system |
| Sep-29-1998 |
A cryptographic key recovery system for generating a cryptographic key for use by a pair of communicating parties while simultaneously providing for its recovery using one or more key recover agents. A... |
| 5802175 |
Computer file backup encryption system and method |
| Sep-1-1998 |
A system and method for generating, storing and retrieving cryptographic keys to be utilized in a processor-based system. In one embodiment, a Touch Memory ("TM") containing unique information is used... |
| 5799086 |
Enhanced cryptographic system and method with key escrow feature |
| Aug-25-1998 |
A cryptographic system with key escrow feature that uses a method for verifiably splitting user's private encryption keys into components and for sending those components to trusted agents chosen by the... |
| 5796830 |
Interoperable cryptographic key recovery system |
| Aug-18-1998 |
A cryptographic key recovery system that is interoperable with existing systems for establishing keys between communicating parties. The sender uses a reversible key inversion function to generate key... |
| 5787169 |
Method and apparatus for controlling access to encrypted data files in a computer system |
| Jul-28-1998 |
In a system in which encrypted information can be protected and maintained by multiple users using passwords in concert, a file with secure data contains both an unencrypted header and an encrypted data... |
| 5768388 |
Time delayed key escrow |
| Jun-16-1998 |
Methods for designing encryption algorithms with different levels of security for different parties: "easier" (but requiring some work nonetheless) to break for some parties (e.g., the government) than... |
| 5768373 |
Method for providing a secure non-reusable one-time password |
| Jun-16-1998 |
The present invention is directed toward providing a secure method to access data when the user has lost or forgotten the user password. In accordance with the invention and in a system where decryption... |
| 5764772 |
Differential work factor cryptography method and system |
| Jun-9-1998 |
Differential work factor cryptographic method, system, and data structure for reducing but not eliminating the work factor required by an authority to break an encrypted message encrypted with a secret... |
| 5764767 |
System for reconstruction of a secret shared by a plurality of participants |
| Jun-9-1998 |
A method for reconstructing a secret, over a public communication channel, using a perfect t-out-of-n secret sharing scheme. The scheme having a dealer which utilizes a delivering procedure for privately... |
| 5761310 |
Communication system for messages enciphered according to an RSA-type procedure |
| Jun-2-1998 |
The procedure involves key numbers "d" and "e" and a modulus N, so hat "N" is the product of two factors "p" and "q" which are prime numbers N=p.q, and e.d=1.sub.MOD.phi.(N), where .phi.(N) is the Euler... |
| 5754659 |
Generation of cryptographic signatures using hash keys |
| May-19-1998 |
A method and apparatus are provided for generating a digital signature that authenticates information of a plurality of different information groups. Information from each group is hashed to produce a... |
| 5745573 |
System and method for controlling access to a user secret |
| Apr-28-1998 |
A system and method for data escrow cryptography are described. An encrypting user encrypts a message using a secret storage key (KS) and attaches a data recovery field (DRF), including an access rule... |
| 5745574 |
Security infrastructure for electronic transactions |
| Apr-28-1998 |
A plurality of certification authorities connected by an open network are interrelated through an authentication and certification system for providing and managing public key certificates. The certification... |
| 5737419 |
Computer system for securing communications using split private key asymmetric cryptography |
| Apr-7-1998 |
A programmed computer secures communications between users of a crypto-system in which each user has an associated asymmetric crypto-key with a public key portion accessible to all system users and a corresponding... |
| 5721777 |
Escrow key management system for accessing encrypted data with portable cryptographic modules |
| Feb-24-1998 |
A cryptographic module, such as a smartcard, is designed to a) store decrypting software programs, and information indicative of predetermined conditions under which an escrow agent is enabled to use the... |
| 5717759 |
Method for certifying public keys in a digital signature scheme |
| Feb-10-1998 |
A method for certifying public keys of a digital signature scheme in a communications system is provided. The secure communications system is one in which there are at least two levels of authorities.... |
| 5708714 |
Method for sharing secret information and performing certification in a communication system that has a plurality of information processing apparatuses |
| Jan-13-1998 |
The object of the present invention is to perform verifiable secret sharing by a practical amount of calculation and a practical amount of communication. In addition, by using this process, a shared digital... |
| 5675649 |
Process for cryptographic key generation and safekeeping |
| Oct-7-1997 |
A process for cryptographic key generation and safekeeping is provided. A plurality of key agents are selected, each having a copy of the source code. One copy of the source code is loaded onto a secure... |
| 5666416 |
Certificate revocation system |
| Sep-9-1997 |
A method of managing certificates in a communication system having a certifying authority and a directory. Preferably, the method begins by having the certifying authority generate certificates by digitally... |
| 5666414 |
Guaranteed partial key-escrow |
| Sep-9-1997 |
A given decryption key is decomposed into at least two parts, for example, a first subkey and a second subkey. The first subkey may be verifiably secret-shared among a set of one or more trustees, whereas... |
