PSC-Watermark: Power Side Channel Based IP Watermarking Using Clock Gates

Abstract

With the ever-increasing re-use of intellectual property (IP) cores in modern system-on-chips (SoCs), it is crucial to prevent security risks such as IP piracy and overuse. Considering that IP watermarking is a potential solution to the copyright protection of IP cores, this paper proposes PSC-Watermark as a power side-channel-based IP authentication methodology using clock gates. PSC-Watermark embeds a power signature with very minimal modification to the IP core. It is done by reusing the existing clock gates to modify the dynamic power consumption inside the IP (in an SoC) based on an applied challenge, and it generates a unique power trace that works as a signature of the IP. Our experimental results show that this power signature can be robustly/effectively verified, even with the interferences emanating from the rest of the functional cores in complex SoCs. We evaluate our technique on several benchmarks of varying size (i.e., MIPS, openMSP430, or1200) in the presence of multiple non-watermarked cores operating in parallel and obtain > 90% confidence rate in proving the ownership of each watermarked IP core. Furthermore, the IP cores are watermarked in a subtle and obfuscated way with < 4% overhead, which makes the proposed technique hard to detect, remove or modify.