1
Martin E Hellman, Bailey W Diffie, Ralph C Merkle: Cryptographic apparatus and method. Stanford University, Flehr Hohbach Test, April 29, 1980: US04200770 (846 worldwide citation)

A cryptographic system transmits a computationally secure cryptogram over an insecure communication channel without prearrangement of a cipher key. A secure cipher key is generated by the conversers from transformations of exchanged transformed signals. The conversers each possess a secret signal an ...


2
Mark J Stefik, Ralph C Merkle, Peter L T Pirolli: System for controlling the distribution and use of digital works having a fee reporting mechanism. Xerox Corporation, Richard B Domingo, May 27, 1997: US05634012 (826 worldwide citation)

A fee accounting mechanism for reporting fees associated with the distribution and use of digital works. Usage rights and fees are attached to digital works. The usage rights define how the digital work may be used or further distributed. Usage fees are specified as part of a usage right. The digita ...


3
Martin E Hellman, Ralph C Merkle: Public key cryptographic apparatus and method. The Board of Trustees of the Leland Stanford Junior University, August 19, 1980: US04218582 (496 worldwide citation)

A cryptographic system transmits a computationally secure cryptogram that is generated from a publicly known transformation of the message sent by the transmitter; the cryptogram is again transformed by the authorized receiver using a secret reciprocal transformation to reproduce the message sent. T ...


4
Ralph C Merkle: Method of providing digital signatures. The Board of Trustees of the Leland Stanford Junior University, Flehr Hohbach Test Albritton & Herbert, January 5, 1982: US04309569 (271 worldwide citation)

The invention comprises a method of providing a digital signature for purposes of authentication of a message, which utilizes an authentication tree function of a one-way function of a secret number.


5
Ralph C Merkle, Dan S Bloomberg, John S Brown: Document copy authentication. Xerox Corporation, Rosen Dainow & Jacobs, October 20, 1992: US05157726 (142 worldwide citation)

A system for authenticating a hard copy of an original document. The system employs a special copying machine at the sender's end together with a special ID card (smart card) or other user identification for activating the special machine, and a special copying machine at the receiving end. At the s ...


6
Ralph C Merkle: Method and apparatus for data encryption. Xerox Corporation, Townsend and Townsend, March 26, 1991: US05003597 (139 worldwide citation)

A method and apparatus for encrypting and decrypting data which operates efficiently on computers of differing architectures is disclosed. Unlike previous encryption/decryption method and apparatus, the present invention executes efficiently in the computer's software. The method uses part of the da ...


7
Ralph C Merkle: Digital signature system and method based on a conventional encryption function. Flehr Hohbach Test Albritton & Herbert, November 14, 1989: US04881264 (110 worldwide citation)

A method of generating digital signatures for signing an infinitely expandable series of messages M.sub.i. An infinitely expandable tree of signature nodes is used, where each node can be used to sign a message. Each node is also used to sign up to k subnodes, where k is an integer greater than one. ...


8
Margery A Eldridge, Michael J Flynn, Christopher M Jones, Ralph C Merkle, Michael G Lamming, David L Pendlebury, Mark Stringer, Michiel F E Kleyn: Secure token-based document server. Xerox Corporation, May 28, 2002: US06397261 (96 worldwide citation)

A system is presented for transmitting document references or tokens between users of integrated wireless and wire-based communication services. The system includes workstations, files servers, printers and other devices coupled to a wire-based network. Mobile computing devices are coupled to the wi ...


9
Margery A Eldridge, Michael J Flynn, Christopher M Jones, Ralph C Merkle, Michael G Lamming, David L Pendlebury, Mark Stringer, Michiel F E Kleyn: Secure token-based document server. Xerox Corporation, July 29, 2003: US06601102 (36 worldwide citation)

A system is presented for transmitting document references or tokens between users of integrated wireless and wire-based communication services. The system includes workstations, files servers, printers and other devices coupled to a wire-based network. Mobile computing devices are coupled to the wi ...


10
Ralph C Merkle: Protected shareware. Xerox Corporation, Thomas M Webster, Phuong Quan Hoang, December 11, 2001: US06330549 (32 worldwide citation)

The functionality of “protected shareware” is controlled by digitally signed messaging protocol. Protective code within the shareware controls the functionality of the shareware in response to authorization messages which are supplied directly or indirectly by the shareware supplier. These messages ...



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