Signature Restoration for Enhancing Robustness of FPGA IP Designs

Abstract

Many watermarking techniques for intellectual property (IP) protection are not resilient to tampering or removal attacks, especially for field programmable gate array (FPGA)-based IP cores. If attacked, the damaged watermarks cannot provide sufficient evidence in front of a court. To address this issue, the authors present a signature restoration scheme. The thought of secret sharing is introduced to share the signature into small watermarks. These watermarks are encoded with Reed-Solomon (RS) codes and embedded into unused lookup tables (LUTs) of used slices. Unlike most of existing techniques, the proposed scheme can restore the signature only by extracting parts of watermarks. So, it is tolerant to some damaged watermarks caused by removal attacks. The experiments show that the proposed scheme incurs no extra hardware resource and timing overhead. The robustness against attacks is much better by comparing to other schemes.