On Securing SSN Architecture using Test Vector Encryption

As System-on-Chip (SoC) architecture becomes increasingly complex, the need for secure and efficient testing methodologies have grown. Recently, the Streaming Scan Network (SSN) was introduced as a testing infrastructure to address the limitations of conventional scan-based architectures in handling complex SoCs. However, SSN architecture presents significant security risks if access control mechanisms are not implemented. Malicious users could exploit the SSN to extract sensitive information from the SoC, posing a serious threat to system security. To address these vulnerabilities, this paper proposes a secure SSN architecture that employs test vector encryption and test response masking. Further, test authorization key is needed to access the test responses. The proposed solution secures the SSN while keeping the functionality intact and additionally reduces the area overhead compared to existing schemes.