Prior art

Prior Art Analysis for U.S. Patent 8,666,062

An analysis of the prior art cited during the prosecution of U.S. Patent 8,666,062 reveals several key patents that define the landscape of finite field arithmetic and its application in cryptography. The core of the '062 patent lies in its two-step process: performing a generalized, "wordsized" finite field operation to get an intermediate result, and then applying a specific, modular reduction to that result. The following analysis examines the most relevant prior art and its potential to anticipate the claims of the '062 patent.

It is important to note that a determination of anticipation under 35 U.S.C. § 102 requires that a single prior art reference discloses, either expressly or inherently, each and every element of a claimed invention.

Cited U.S. Patent References

1. U.S. Patent No. 5,982,895: "Finite field inverse circuit"

• Full Citation: Schroeppel, R., et al., U.S. Patent No. 5,982,895, filed December 24, 1997, and issued November 9, 1999.
• Brief Description: This patent discloses a hardware implementation for calculating multiplicative inverses in a finite field, a fundamental operation in elliptic curve cryptography. The invention describes a circuit that uses a series of iterative steps to perform the inversion, which is a key component of more complex cryptographic calculations.
• Potential Anticipation of Claims: The '895 patent focuses on a specific finite field operation (inversion) and a particular hardware implementation. While it addresses a core cryptographic calculation, it does not appear to disclose the broader, two-step method claimed in the '062 patent. The '062 patent's innovation lies in its modular approach of separating the general "wordsized" operation from the specific modular reduction, making it adaptable to various finite fields. The '895 patent, in contrast, describes a more integrated and specific solution for a single operation. Therefore, it is unlikely that the '895 patent would be found to anticipate the claims of the '062 patent.

2. U.S. Patent No. 6,189,021: "Finite field arithmetic processor"

• Full Citation: Zukowski, J., U.S. Patent No. 6,189,021, filed March 17, 1999, and issued February 13, 2001.
• Brief Description: This patent describes a processor specifically designed to perform arithmetic operations in finite fields. The processor is configurable to handle different field sizes and uses a set of instructions to perform calculations such as addition, multiplication, and inversion.
• Potential Anticipation of Claims: The '021 patent describes a configurable processor for finite field arithmetic, which shares some conceptual ground with the '062 patent's "finite field engine." However, a key distinction lies in the '062 patent's explicit two-step process of generating an "unreduced result" followed by a separate modular reduction. The '021 patent, while configurable, does not appear to explicitly teach this modular software architecture. Its focus is more on the hardware and instruction set of the processor itself. A deeper analysis would be required to determine if this two-step process is inherent in the '021 patent's disclosure, but on its face, it does not appear to anticipate the specific method claimed in the '062 patent.

3. U.S. Patent No. 6,233,603: "Method and apparatus for performing finite field multiplication"

• Full Citation: Moshier, S., U.S. Patent No. 6,233,603, filed July 28, 1999, and issued May 15, 2001.
• Brief Description: This patent discloses a method for performing multiplication in finite fields, particularly for use in cryptography. The method is designed to be efficient and adaptable to different field sizes.
• Potential Anticipation of Claims: Similar to the '895 patent, the '603 patent focuses on a specific finite field operation—multiplication. It teaches an efficient method for this operation but does not describe the broader, two-stage architectural approach of the '062 patent, which separates the core arithmetic from the modular reduction. The '062 patent's claims are directed at a system and method for performing a range of finite field operations using this modular design, not just a single operation like multiplication. Thus, it is unlikely that this patent anticipates the claims of the '062 patent.

4. U.S. Patent No. 6,904,452: "Finite field multiplier"

• Full Citation: Rosati, T., et al., U.S. Patent No. 6,904,452, filed November 8, 2002, and issued June 7, 2005.
• Brief Description: This patent describes a multiplier for finite field elements that is designed to be area-efficient and high-speed, making it suitable for implementation in hardware. The invention focuses on the optimization of the multiplication process itself.
• Potential Anticipation of Claims: The '452 patent, like the '603 patent, is focused on the specific operation of multiplication. It provides a detailed hardware architecture for an efficient multiplier. It does not, however, disclose the '062 patent's more abstract, two-step software method of separating a general "wordsized" operation from a field-specific modular reduction. The claims of the '062 patent are broader in scope, covering a method applicable to various finite field operations, not just multiplication, and are defined by this modular software structure. Therefore, the '452 patent is unlikely to anticipate the '062 patent's claims.

Summary of Prior Art Analysis

The prior art cited against U.S. Patent 8,666,062 primarily consists of patents that disclose specific hardware implementations or optimized methods for individual finite field operations (multiplication and inversion). While these references establish the context and importance of such calculations in cryptography, none appear to explicitly or inherently disclose the key inventive concept of the '062 patent: a modular and flexible system that separates a general, "wordsized" arithmetic step from a specific, interchangeable modular reduction step. This two-part process, which allows the "finite field engine" to be easily adapted to different cryptographic schemes and field sizes without rewriting the core logic, appears to be the novel contribution of the '062 patent. Consequently, based on the cited references, a strong argument can be made that the claims of the '062 patent are not anticipated by this prior art.