Analog Mixed-Signal IC Obfuscation with Shared Key Dependencies
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current security measures for integrated circuits (ICs) are inadequate in protecting analog mixed-signal (AMS) circuits, which are vulnerable to counterfeiting, overproduction, reverse engineering, and Trojan insertion, especially as the IC manufacturing flow transitions to a horizontal model with untrusted third-parties, and existing hardware security techniques are mostly applicable to digital circuits, not analog.
Innovation Solution
A system and method that concurrently secures both analog and digital circuit blocks of AMS ICs by implementing parameter-based obfuscation techniques for the analog components and XOR-based logic locking strategies for the digital parts, generating functional and behavioral dependencies between the domains to increase security and the effective key space.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If hardware security measures are implemented for digital circuits, then security is improved, but these measures are not suitable for analog circuits
Solution Approach 1:
The patent creates a universal security framework that works across both digital and analog domains. The shared key mechanism and functional dependency architecture allow the same security principles to be applied to heterogeneous circuit types (analog, digital, mixed-signal), making the security solution universally applicable rather than domain-specific
Solution Approach 2:
The patent segments the security mechanism into independent components: key generation, functional dependency creation, and verification modules. These segmented security functions can be selectively applied to different circuit blocks (analog, digital, or mixed-signal) while maintaining overall system security through the shared key architecture
2Ease of manufacture
If analog and digital circuit blocks are secured independently, then implementation is simpler, but adversaries can isolate and attack individual blocks
Solution Approach 1:
The patent merges the security of analog and digital blocks by creating functional dependencies between them through shared keys. The security mechanisms of different circuit blocks are combined into a unified security architecture where compromising one block cannot succeed without compromising the other, as they share cryptographic dependencies
Solution Approach 2:
The patent introduces functional dependencies and shared key mechanisms as intermediaries between analog and digital circuit blocks. These intermediaries create cryptographic linkages that prevent isolation attacks, as the intermediary structures (shared keys, functional dependencies) ensure that security validation requires both blocks to be intact and correctly configured
3Reliability
If security measures are added to protect against counterfeiting and Trojans, then security is improved, but device complexity increases
Solution Approach 1:
The patent changes the security approach from adding complex physical circuit structures to modifying functional parameters and behavioral characteristics. By embedding security in the functional dependencies and key-based control logic rather than complex hardware structures, the patent achieves enhanced security with minimal impact on device complexity
Solution Approach 2:
The security mechanism uses the circuit's own functional behavior and existing operational parameters to provide security validation. The circuit blocks themselves participate in the security verification process through their functional dependencies, eliminating the need for separate complex security validation circuits and reducing overall device complexity
Data Source
AI summary
The transition to a horizontal integrated circuit (IC) design flow has raised concerns regarding the security and protection of IC intellectual property (IP). Obfuscation of an IC has been explored as a potential methodology to protect IP in both the digital and analog domains in isolation. However, novel methods are required for analog mixed-signal circuits that both enhance the current disjoint implementations of analog and digital security measures and prevent an independent adversarial attack of each domain. A methodology generates functional and behavioral dependencies between the analog and digital domains that results in an increase in the adversarial key search space. The dependencies between the analog and digital keys result in a 3× increase in the number of iterations required to complete the SAT attack.