Public key cryptographic apparatus and method
Cryptographic communications system and method
Cryptographic key sharing circuit and method using code correction
Exponentiation cryptographic apparatus and method
Method for establishing user authenication with composite session keys among cryptographically communicating nodes
Controlled use of cryptographic keys via generating station established control values
Key distribution method
Mobile communication system
Cryptographic communication method and cryptographic communication device
Cryptographic system allowing encrypted communication between users with a secure mutual cipher key determined without user interaction Patent #: 5150411
ApplicationNo. 069577 filed on 05/28/1993
US Classes:713/171, Having key exchange380/2, EQUIPMENT TEST OR MALFUNCTION INDICATION380/28, PARTICULAR ALGORITHMIC FUNCTION ENCODING380/46, Nonlinear (e.g., pseudorandom)380/283, User-to-user key distributed over data link (i.e., no center)713/181Message digest travels with message
ExaminersPrimary: Gregory, Bernarr E.
Attorney, Agent or Firm
International ClassesH04L 009/08
AbstractA system for the secure communication of a message from a transmitting user to a receiving user using a split key scheme. Each user generates a key component using a cryptographic engine. The key component is a pseudorandom sequence of bits with an appended error detection field which is mathematically calculated based on the pseudorandom sequence. This key component is then sent out on a communications channel from the transmitting user to the receiving user. The receiving user also sends its key component to the transmitting user. Each location performs a mathematical check on the key component received from the other location. If the key component checks pass at both locations, the transmit key component and the receive key component, including the error detection fields, are combined at both locations, forming identical complete keys at both locations. The identical complete keys are then used to initiate the cryptographic engines at both locations for subsequent encryption and decryption of messages between the two locations.