1
William Friedrich Ehrsam, Carl H W Meyer, Robert Lowell Powers, Paul Norman Prentice, John Lynn Smith, Walter Leonard Tuchman: Block cipher system for data security. International Business Machines Corporation, Edwin Lester, May 18, 1976: US03958081 (204 worldwide citation)

A device for ciphering message blocks of data bits under control of a cipher key. The cipher device performs an enciphering process for each message block of data by carrying out a predetermined number of iteration operations in the first of which a first half of the message block of data bits is fi ...


2
William F Ehrsam, Robert C Elander, Stephen M Matyas, Carl H W Meyer, Richard J Sahulka, Walter L Tuchman: Cryptographic file security for multiple domain networks. International Business Machines Corporation, Edwin Lester, May 13, 1980: US04203166 (203 worldwide citation)

A file security system for data files created at a first host system in one domain and recovered at a second host system in another domain of a multiple domain network. Each of said host systems contain a data security device provided with multiple host keys capable of performing a variety of crypto ...


3
William F Ehrsam, Robert C Elander, Stephen M Matyas, Carl H W Meyer, John L Smith, Walter L Tuchman: Cryptographic file security for single domain networks. International Business Machines Corporation, Edwin Lester, December 9, 1980: US04238854 (189 worldwide citation)

A file security system for data files associated with a host data processing system. The host system includes a data security device which contains a secure host master key and is capable of performing a variety of cryptographic operations. At initialization time, the host system generates a series ...


4
Stephen M Matyas, Carl H W Meyer: Method for authenticating the identity of a user of an information system. International Business Machines Corporation, Edwin Lester, August 19, 1980: US04218738 (166 worldwide citation)

Secure hardware is provided for cryptographically generating a verification pattern which is a function of a potential computer user's identity number, the potential computer user's separately entered password, and a stored test pattern. The test pattern for each authorized computer user is generate ...


5
William F Ehrsam, Robert C Elander, Stephen M Matyas, Carl H W Meyer, Robert L Powers, Paul N Prentice, John L Smith, Walter L Tuchman: Cryptographic communication security for single domain networks. International Business Machines Corporation, Edwin Lester, December 9, 1980: US04238853 (152 worldwide citation)

A communication security system for data transmissions between remote terminals and a host system. The remote terminals and the host system include data security devices capable of performing a variety of cryptographic operations. At initialization time, a host master key is written into the host da ...


6
William F Ehrsam, Robert C Elander, Lloyd L Hollis, Richard E Lennon, Stephen M Matyas, Carl H W Meyer, Jonathan Oseas, Walter L Tuchman: Cryptographic communication security for multiple domain networks. International Business Machines Corporation, Edwin Lester, October 7, 1980: US04227253 (125 worldwide citation)

A communication security system for data transmissions between different domains of a multiple domain communication network where each domain includes a host system and its associated resources of programs and communication terminals. The host systems and communication terminals include data securit ...


7
Richard E Lennon, Stephen M Matyas, Carl H W Meyer, Jonathan Oseas, Paul N Prentice, Walter L Tuchman: Cryptographic verification of operational keys used in communication networks. International Business Machines Corporation, Edwin Lester, March 11, 1980: US04193131 (125 worldwide citation)

In a data communication network providing communication security for communication sessions between a first station and a second station where each station has cryptographic apparatus provided with an operational key which should be common to both stations for cryptographic operations, an operationa ...


8
William Friedrich Ehrsam, Carl H W Meyer, Robert Lowell Powers, John Lynn Smith, Walter Leonard Tuchman: Product block cipher system for data security. International Business Machines Corporation, Edwin Lester, June 8, 1976: US03962539 (124 worldwide citation)

A device for ciphering a block of data bits under control of a cipher key. The cipher device performs a ciphering process for the block of data by carrying out an operation in which the block of data bits is first expanded by duplicating predetermined ones of the data bits. The data bits of the expa ...


9
Stephen M Matyas Jr, Carl H W Meyer, Bruno O Brachtl: Controlled use of cryptographic keys via generating station established control values. International Business Machines, C Lamont Whitham, Michael E Whitham, July 18, 1989: US04850017 (109 worldwide citation)

A method for controlling the use of a cryptographic key at a using station by a generating station in a network of generating and using stations is disclosed. A control value specifying the use of the cryptographic key is transmitted with a generated cryptographic key to at least two designated usin ...


10
Bruno O Brachtl, Don Coppersmith, Myrna M Hyden, Stephen M Matyas Jr, Carl H W Meyer, Jonathan Oseas, Shaiy Pilpel, Michael Schilling: Data authentication using modification detection codes based on a public one way encryption function. International Business Machines Corporation, John E Hoel, March 13, 1990: US04908861 (83 worldwide citation)

A cryptographic method and apparatus are disclosed which transform a message or arbitrary length into a block of fixed length (128 bits) defined modification detection code (MDC). Although there are a large number of messages which result in the same MDC, because the MDC is a many-to-one function of ...