Software security method and systems

Patent 4747139 Issued on May 24, 1988. Estimated Expiration Date:

October 21, 2006. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

3711645

3808365

Random digital code generator
Patent #: 4115657
Issued on: 09/19/1978
Inventor: Morgan

Computer software security system
Patent #: 4120030
Issued on: 10/10/1978
Inventor: Johnstone

Coding method and system with enhanced security
Patent #: 4225935
Issued on: 09/30/1980
Inventor: Zscheile, Jr. , et al.

Crypto microprocessor for executing enciphered programs
Patent #: 4278837
Issued on: 07/14/1981
Inventor: Best

Crypto microprocessor using block cipher
Patent #: 4319079
Issued on: 03/09/1982
Inventor: Best

Data security module
Patent #: 4352952
Issued on: 10/05/1982
Inventor: Boone , et al.

Cryptographic encoder-decoder
Patent #: 4408093
Issued on: 10/04/1983
Inventor: Place

Cryptographic decoder for computer programs
Patent #: 4433207
Issued on: 02/21/1984
Inventor: Best

More ...

Inventor

Taaffe, James L.

Application

No. 06/921851 filed on 10/21/1986

US Classes:

380/44, Having particular key generator380/46, Nonlinear (e.g., pseudorandom)705/55, Requiring a supplemental attachment or input (e.g., dongle) to open713/193By stored data protection

Examiners

Primary: Cangialosi, Salvatore

Attorney, Agent or Firm

Hamilton, Brook, Smith & Reynolds

International Classes

G06F 1/00 (20060101)
G06F 21/00 (20060101)

Abstract

Encrypted digital information in a data processing system is decrypted using a key which is a word sequence. The key is generated in a hardware module which is a single chip microprocessor. Individual words of the key word sequence generated by the module are generated as a function of a plurality of words of the input key word sequence. To that end, the microprocessor is programmed as a finite state machine. The hardware module may be combined with a storage medium in a software package. The decryption routines and a key sequence to be applied to the key generator are stored with the application software on the storage medium. To decrypt the application software, the stored key sequence is applied to the key generator to obtain an output key sequence. A computer system may include an encryption/decryption module and a key generator module to encrypt software and data prior to outputting the software or data from the system. Identical key generators may be utilized for encryption and decryption in a secure network.