Invalidity dossier
US 7027597
Pre-computation and dual-pass modular arithmetic operation approach to implement encryption protocols efficiently in electronic integrated circuits
Current assignee: Cisco Technology Inc
Added 9/21/2026, 9:43:06 AM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview: US 7027597 B1
Title: Pre-computation and dual-pass modular arithmetic operation approach to implement encryption protocols efficiently in electronic integrated circuits
Patent number: US 7027597 B1
Application number: US09/955,902
Inventors: Mihailo M. Stojancic, Mahesh S. Maddury, Kenneth J. Tomei
Assignee: Cisco Technology, Inc. (original and current assignee as listed)
Priority/filing date: 2001-09-18
Publication (grant) date: 2006-04-11
Legal status (as listed): Expired – Fee Related; adjusted expiration 2023-10-01
Purpose: The invention relates to encryption of electronic messages, specifically to using pre-computation and dual-pass modular arithmetic operations to implement encryption protocols efficiently in electronic hardware such as integrated circuits. Some encryption protocols are based on modular mathematics, such as Diffie-Hellman and RSA.
Plain-language scope: The patent describes a method for encryption and decryption of electronic messages based on an encryption protocol, using a pre-computation and dual-pass modular operation approach. A message encrypted according to the protocol is received, and at least one part of another message is generated based on the received message and a modular operation. The modular operation is based on two applications of Montgomery's method with a constant chosen not to be a power of two, two operands, and a modulus. A second electronic message is created by pre-computing another constant based on the modulus. An intermediate result is determined and stored in memory based on a first application of Montgomery's method for the modular operation, one operand, and the pre-computed constant. A final result is determined based on a second application of Montgomery's method, the intermediate result, and the other operand.
Stated applicability: Encryption protocols may include, but are not limited to, RSA, Diffie-Hellman, and digital signature algorithm (DSA) protocols. Modular operations include, but are not limited to, modular multiplication.
Source: https://patents.google.com/patent/US7027597/en
What the excerpt does not establish: The excerpt is partial and does not provide the full claims, complete detailed description, all cited prior art, or prosecution history. It does not establish validity, enforceability, litigation, or ownership transfers. Dates and legal status are as listed and may be assumptions per the source.
Generated 10/1/2026, 10:01:52 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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