Logic Circuit Digital Signatures for Consumable Authentication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Non-authorized third parties attempt to reverse engineer or counterfeit logic circuits of Original Equipment Manufacturers (OEMs) by connecting to their apparatuses without authorization, posing a challenge in verifying the authenticity of replaceable print apparatus components.
Innovation Solution
A digital signature is generated using a private key and stored on the consumable, with a corresponding public key in the host firmware to validate its authenticity, allowing only genuine components to be accepted, and a flexible schema for specifying attributes and data is used to verify the signature efficiently.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If digital signature verification is implemented to authenticate replaceable print apparatus components, then security against counterfeiting is improved, but device complexity increases due to key management and verification procedures
Solution Approach 1:
The patent applies preliminary action by pre-storing the public key in the host firmware during manufacturing, before any verification operations are needed. This eliminates the need for complex key distribution systems during operation, as the verification infrastructure is already in place and ready to authenticate replaceable components securely.
Solution Approach 2:
The patent uses copying by storing the public key (a copy of the cryptographic identity) in the host firmware, allowing verification of the private key held by the replaceable component. This enables authentication without requiring the original private key to be present in the host, simplifying the security architecture while maintaining reliability.
2Measurement precision
If comprehensive attribute data is stored for signature verification, then verification accuracy is improved, but memory consumption increases
Solution Approach 1:
The patent applies extraction by isolating only the essential elements needed for verification: the public key and specific attribute data. Non-essential data is excluded from storage, allowing accurate verification while minimizing memory consumption. The system extracts precisely what is needed rather than storing comprehensive datasets.
Solution Approach 2:
The patent applies local quality by storing different types of data with different importance levels in appropriate locations. The public key is stored in firmware (permanent storage), while attribute data is stored in memory (temporary storage). This differentiated approach optimizes both verification accuracy and memory efficiency by placing each data element where it is most needed.
Data Source
AI summary
A logic circuitry package includes an interface to communicate with a controller and a logic circuit. The logic circuit includes a memory arrangement storing a first digital signature, a second digital signature, and a third digital signature signed over the first digital signature and the second digital signature. The logic circuit is configured to receive at least one request from the controller; and transmit the first digital signature, the second digital signature, and the third digital signature to the controller in response to the at least one request.