1
Feistel Horst: Centralized verification system. International Business Machines Corporation, Siber Victor, March 19, 1974: US3798605 (258 worldwide citation)

This specification describes a multi-terminal data processing system having means and process for verifying the identity of subscribers to the system. Validity of a terminal request for communication with the data processing system are determined on the basis of a centralized verification system. Ea ...


2
Feistel Horst: Block cipher cryptographic system. International Business Machines Corporation, Siber Victor, March 19, 1974: US3798359 (221 worldwide citation)

A cryptographic system for encrypting a block of binary data under the control of a key consisting of a set of binary symbols. The cryptographic system is utilized within a data processing environment to ensure complete privacy of data and information that is stored or processed within a computing s ...


3
Feistel Horst: Step code ciphering system. International Business Machines Corporation, Siber Victor, March 19, 1974: US3798360 (119 worldwide citation)

This specification discloses a system that provides multiple level encipherment of a block of data by means of a stepped block cipher process. A data stream consisting of digital information is segmented into blocks of dimension D, each block is enciphered by means of a block cipher cryptographic sy ...


4
Smith John Lynn: Recirculating block cipher cryptographic system. International Business Machines Corporation, Siber Victor, March 12, 1974: US3796830 (86 worldwide citation)

This is a cryptographic system for enciphering a block of binary data under the control of a subscriber cipher key consisting of a preassigned combination of binary symbols. The block of data is processed on a segmented basis with each segment of data being serially transformed in accordance with co ...


5
Frei Armin H, Schindler Hans R, Vettiger Peter: Method and device for coding and decoding video signals. International Business Machines Corporation, Siber Victor, July 23, 1974: US3825832 (39 worldwide citation)

Method and device for coding and decoding video signals employing two different modes: Delta Coding for regions of minor amplitude changes, and DPCM Coding for edges which exhibit large amplitude changes. Switching between modes is effected by the bit stream carrying the video information, with a mi ...


6
Zafiropulo Pitro Alois, Zihlmann Franz Xaver: Synchronous disconnection and rearrangement. International Business Machines Corporation, Siber Victor, April 8, 1975: US3876983 (28 worldwide citation)

This is a communication loop system having a bidirectional transmission capability between terminals. The system is comprised of switching units which allow isolation of a loop segment and the establishment of an operable folded loop for the remaining non-isolated loop portions of the system. In add ...


7
Gaensslen Fritz H, Terman Lewis M: Complementary mosfet device structure. International Business Machines Corporation, Kilgannon Jr Thomas J, Siber Victor, October 8, 1974: US3840888 (12 worldwide citation)

A complementary field effect device which incorporates pairs of source and drain regions and a common channel region is disclosed. One of the field effect transistors which shares the common channel region is an n-channel device while the other is a p-channel device. When these devices are operated, ...


8
Bahl Lalit R, Barnea Daniel I, Kobayashi Hisashi: Image compaction system. International Business Machines Corporation, Siber Victor, September 3, 1974: US3833900 (10 worldwide citation)

A data compaction system wherein segmented binary data that has redundancy between segments is compacted by means of differential run-length encoding. For compaction of document digitized data, the segments represent lines on the document. Black image points on the document which are represented by ...


9
Franaszek Peter Anthony: Limitation of a.c. coupling distortion in magnetic recording. International Business Machines Corporation, Siber Victor, October 8, 1974: US3840854 (7 worldwide citation)

This is an apparatus and method for reducing a. c. coupling distortion which is present in a transformer coupled saturated digital magnetic recording system. All data that is to be recorded is partitioned into blocks of specified lengths. Each block of data is then coded so as to be preceded by a pr ...


10
Kurtzberg Jerome Marvin: Recursive shift register for controlling a data processor. International Business Machines Corporation, Schlemmer Roy R, Siber Victor, December 2, 1975: US3924270 (3 worldwide citation)

This is a data processor having two modes of operation. In a first mode of operation, computer instructions are fetched from storage and placed in an instruction register for controlling the internal logical operations executed within the processor. In a second mode of operation, a recursive shift r ...