PUF Circuit Offline Authentication via Elliptic Curve Cryptography
Solution Overview
Problem
Traditional PUF-based authentication ICs require online verification, making them impractical and vulnerable to attacks, especially when connection to a manufacturer's database is unavailable, and alternative methods without PUF circuits are not immune to reverse engineering.
Innovation Solution
A system and method using a PUF circuit to generate a private key, computing a public key through elliptic curve cryptography, and storing a signed public key certificate in non-volatile memory, allowing offline authentication via a host device using asymmetric cryptography.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional PUF-based authentication ICs are used with online verification, then authentication security is improved, but device complexity and dependency on manufacturer database increase
Solution Approach 1:
The patent extracts the authentication functionality from the manufacturer database dependency by embedding the PUF circuit and cryptographic key generation directly into the authentication IC. This allows the device to perform self-authentication without requiring continuous connection to the manufacturer's database, thereby reducing device complexity while maintaining security.
Solution Approach 2:
The patent applies preliminary action by pre-configuring the authentication IC with a PUF circuit that generates unique cryptographic keys during manufacturing. This preliminary setup enables the device to autonomously perform authentication operations without requiring ongoing database access, eliminating the need for complex online verification infrastructure.
2Reliability
If PUF-generated secrets are used, then resistance to reverse engineering is improved, but requirement for online authentication increases
Solution Approach 1:
The patent implements self-service by enabling the authentication IC to autonomously generate and use PUF-based cryptographic keys for authentication operations. The device serves itself by performing authentication locally without requiring manual intervention or online verification, thereby maintaining reverse engineering resistance while improving ease of operation.
3Ease of operation
If alternative approaches without PUF circuits are used, then ease of operation is improved, but security against reverse engineering deteriorates
Solution Approach 1:
The patent merges the benefits of PUF-based security with convenient operational characteristics by integrating the PUF circuit directly into the authentication IC. This combination allows the device to maintain strong resistance to reverse engineering while enabling straightforward authentication operations without requiring separate security systems or complex online verification processes.
Data Source
AI summary
Presented are systems, devices, and methods for reliably authenticating asymmetric cryptography-based ICs based on Physically Unclonable Functions (PUFs) that are immune to reverse engineering. Various embodiments of the invention enhance the level of security in IC architectures without the need to connect to a remote certification authority, thereby, eliminating shortfalls associated with online authentication. Certain embodiments accomplish this by using a PUF-generated secure private key that need never be output by or exported from the PUF.