| 5633928 |
Key escrow method with warrant bounds |
| May-27-1997 |
A key escrow technique is disclosed which permits cryptographic limits on wiretapping warrants. Specifically, time limits on wiretaps may be enforced. In addition, the wiretapper is targeted to a specific... |
| 5604806 |
Apparatus and method for secure radio communication |
| Feb-18-1997 |
Characteristics of the radio channel are used to establish key sequences for use in encrypting communicated information. These characteristics are the short-term reciprocity and rapid spatial decorrelation... |
| 5602915 |
Process for the control of secret keys between two smart cards |
| Feb-11-1997 |
A process for controlling communication between a first and a second smart card using key-based cryptography is provided. In the disclosed process, a first identity code is stored in the first smart card... |
| 5588062 |
Secure communication setup method |
| Dec-24-1996 |
A call is connected between secure terminals (16) through a network (12). If a network address for the call is included on an approved list (46), a secure call setup procedure (54) is performed automatically.... |
| 5583939 |
Secure, swift cryptographic key exchange |
| Dec-10-1996 |
Using the present cryptographic key exchange protocol, a first of two cryptographic units selects quantities "A" and "B." That same unit then applies a mathematical function ".PHI..sub.1 " to A and B to... |
| 5583941 |
Imaging processor |
| Dec-10-1996 |
In an image processor, a scramble device performs scramble processing to deform a document image by using scramble conditions by rearranging pixel data in the document image read by a reader. The scramble... |
| 5577121 |
Transaction system for integrated circuit cards |
| Nov-19-1996 |
A transaction system and method of conducting a transaction between in integrated circuit (IC) card and a transaction terminal which includes a security module comprises establishing communication between... |
| 5481613 |
Computer network cryptographic key distribution system |
| Jan-2-1996 |
Novel cryptographic key distribution techniques to be used in large computer networks are disclosed. The techniques require trusted key release agent systems in each security domain. The encryptor of a... |
| 5465300 |
Secure communication setup method |
| Nov-7-1995 |
A call is connected between secure terminals (16) through a network (12). If a network address for the call is included on an approved list (46), a secure call setup procedure (54) is performed automatically.... |
| 5434920 |
Secure telecommunications |
| Jul-18-1995 |
A security node disposed in the telecommunications network connecting calling and called parties transforms information (which can be voice, data, facsimile, video and other types of calls or messages)... |
| 5432850 |
Method and apparatus for secure data transmission |
| Jul-11-1995 |
A method for secure transmission of data having a destination address and a source address on a shared communication network comprising the steps of transmitting a multiplicity of data frames, each containing... |
| 5375169 |
Cryptographic key management method and apparatus |
| Dec-20-1994 |
A 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... |
| 5349642 |
Method and apparatus for authentication of client server communication |
| Sep-20-1994 |
The present invention provides a method and apparatus for message packet authentication to prevent the forging of message packets. After a message packet is created, a secret session key is preappended... |
| 5307410 |
Interferometric quantum cryptographic key distribution system |
| Apr-26-1994 |
An apparatus and method for distributing cryptographic key information is described incorporating a quantum channel for conveying dim and reference light pulses, a timing channel, a source of coherent... |
| 5247578 |
Process for exchange of rights between microprocessor cards |
| Sep-21-1993 |
A process for exchange of rights between microprocessor cards, wherein multiple keys (K1, K2, . . . ) and varied keys (Ka5, Kb3) are used. A card to be debited calculates a voucher with varied key (Ka5)... |
| 5245658 |
Domain-based encryption |
| Sep-14-1993 |
A domain-based encryption system which uses identical domains known only to the parties involved in the communication. An encrypted message is sent between communicating parties which consists of a stream... |
| 5243649 |
Apparatus and method for quantum mechanical encryption for the transmission of secure communications |
| Sep-7-1993 |
An apparatus and method that permit the transmission of secure communications. The invention uses quantum mechanical effects to establish nonlocal correlations between a pair of photons. This is analogous... |
| 5241599 |
Cryptographic protocol for secure communications |
| Aug-31-1993 |
A cryptographic communication system. The system, which employs a novel combination of public and private key cryptography, allows two parties, who share only a relatively insecure password, to bootstrap... |
| 5241595 |
Communication control section for facsimile equipment having a secure communication function |
| Aug-31-1993 |
A facsimile equipment including a memory for storing a cipher key data, ten number keys for inputting the cipher key data, a DTMF signal receiving circuit for converting a DTMF signal received through... |
| 5182770 |
System and apparatus for protecting computer software |
| Jan-26-1993 |
An integrated software piracy prevention system incorporates several characteristic identification codes identifying installation and software components. A separate security device is attached to and... |
| 5010572 |
Distributed information system having automatic invocation of key management negotiations protocol and method |
| Apr-23-1991 |
The invention is an improved distributed information system which automatically provides for the transmission of security protocol data units between end-users of a distributed information system. The... |
| 4991209 |
Random local message encryption |
| Feb-5-1991 |
Data transmission to an aircraft is secured by encrypting the data between a remote data source and the aircraft. The encryption is initiated when a random number is coupled to the remote location where... |
| 4853962 |
Encryption system |
| Aug-1-1989 |
A method for encrypting signals utilizes the receiver serial number to generate an index number which is used in turn to select an encryption table from among a plurality of such tables. The index number... |
| 4805216 |
Method and apparatus for continuously acknowledged link encrypting |
| Feb-14-1989 |
The method and apparatus of the invention described herein provide confidential communications between two or more stations whereby the exchanged messages themselves provide the necessary enciphering keys... |
| 4703503 |
Cryptographic system using pseudocomplements of vector Boolean algebra |
| Oct-27-1987 |
By using properties of pseudocomplements of vector Boolean algebra defined herein, a vector Boolean value which represents a plaintext of a message is converted to an enciphered text. The enciphered text... |
| 4677670 |
Paired-secure message identification controller for computers and the like |
| Jun-30-1987 |
A paired-secure message identification controller for computers and the like is provided which yields secure communications between two computers with the invention installed. The message originator provides... |
| 4649233 |
Method for establishing user authenication with composite session keys among cryptographically communicating nodes |
| Mar-10-1987 |
A method for authenticating nodes/users and in protecting data flow between nodes. This is facilitated by creating a dialogue involving authenticated encryption among the nodes. During each session, a... |
| 4638120 |
Method and system for transmission of confidential data |
| Jan-20-1987 |
In a system for the transmission of confidential data between a transmitter 1) and a receiver (3), the transmitter (1) transmits a standard key E to the receiver (3). The standard key E preferably is a... |
| 4633037 |
Generation of identification keys |
| Dec-30-1986 |
Commercial transactions conducted over a telecommunications link are verified using a transaction key available at both ends of the link. The transaction key is produced by combining (1) data supplied... |
| 4578532 |
Method and apparatus for code transmission |
| Mar-25-1986 |
A transmission code required for decoding an encoded transmission of messages between a transmitting station and a receiving station is first transmitted from one station to the other. Previously identified... |
| 4465153 |
Method of coding and decoding messages |
| Aug-14-1984 |
Method of coding and decoding messages wherein a basic key and a random message key, which is transmitted prior to the message, are used. Using a plurality of basic keys entails the problem that the proper... |
| 4451884 |
Cycle stealing I/O controller with programmable offline mode of operation |
| May-29-1984 |
A dual mode microprocessor acts either as a front-end IO controller processor relative to a primary host processor and device or as a secondary data processor having independent storage, processing and... |
| 4429180 |
Apparatus for simultaneous generation of key at two locations |
| Jan-31-1984 |
An apparatus for simultaneously generating identical cipher key at two remote terminals in a manner which prohibits interception of the key by unauthorized persons. A circuit comprising three separate... |
