Key controlled block cipher cryptographic system
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United States of America Patent
Stats
-
Mar 10, 1981
Grant Date -
N/A
app pub date -
Mar 25, 1975
filing date -
Mar 25, 1975
priority date (Note) -
Expired
status (Latency Note)
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Abstract
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 may be utilized within a data processing environment to ensure complete privacy of data and information that is stored or processed within a computing system. All authorized subscribers who are permitted access to data within the network are assigned a unique key consisting of a combination of binary symbols. The central processing unit within the computing network contains a complete listing of all distributed authorized subscriber keys. All communications transmitted from terminal input are encrypted into a block cipher by use of the cryptographic system operating under the control of the subscriber key which is inputed to the terminal device. At the receiving station or central processing unit, an identical subscriber key which is obtained from internal tables stored within the computing system is used to decipher all received ciphered communications.
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- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
- INTERNATIONAL BUSINESS MACHINES CORPORATION
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Adler, Roy L | Ossining, NY | 7 | 483 |
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| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
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