Cryptography – Particular algorithmic function encoding – Nbs/des algorithm
Patent
1989-04-25
1990-07-24
Buczinski, Stephen C.
Cryptography
Particular algorithmic function encoding
Nbs/des algorithm
380 21, 380 42, 380 43, 380 44, 380 45, 380 50, H04N 7167, H04L 902
Patent
active
049440063
ABSTRACT:
A bit packet communication system includes a head-end having a software implemented 16 bit shift register with a plurality of feed-forward taps and a different plurality of feedback taps for simultaneously dividing and multiplying the input data bit packet to provide an output bit packet that is both encrypted and error protected. Dynamic encryption is provided by utilizing an initial preset for the software corresponding to a preset encryption key for the shift register. Authorized subscriber terminals are provided with memories and decryption keys are downloaded. The bit packets are assembled with a global bit packet encrypted with a global encryption key and subsequent individually addressed bit packets encrypted with address keys. The address keys and terminal addresses are permanently stored in the subscriber terminal memories. The global encryption keys are changed periodically. Means are provided in each subscriber terminal for storing a number of global decryption keys which are cycled through in attempts to decrypt the global packets. One of the global decryption keys is a permanent default key associated with the subscriber terminal to assure that communication with that terminal is possible despite a lack of knowledge of the terminal address or the other global decryption keys in its memory.
REFERENCES:
patent: 4159468 (1979-06-01), Barnes
patent: 4292650 (1981-09-01), Hendrickson
patent: 4323921 (1982-04-01), Guillou
patent: 4337483 (1982-06-01), Guillou
patent: 4354201 (1982-10-01), Sechet et al.
patent: 4434322 (1984-02-01), Ferrell
patent: 4465901 (1984-08-01), Best
patent: 4494142 (1985-01-01), Mistry
patent: 4531021 (1985-07-01), Bluestein et al.
patent: 4639548 (1987-01-01), Oshima et al.
patent: 4694491 (1987-09-01), Horne et al.
Citta Richard W.
Gosc Paul M.
Mutzabaugh Dennis M.
Sgrigonoli Gary J.
Buczinski Stephen C.
Zenith Electronics Corporation
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