Power signature watermarking of IP cores for FPGAs

In this paper, we introduce a new method for watermarking of IP cores for FPGA architectures where the signature (watermark) is detected at the power supply pins of the FPGA. This is the first watermarking method where the signature is extracted in this way. We are able to sign IP cores at the netlist as well as the bitfile level, so a wide spectrum of cores can be protected. In principle, the proposed power watermarking method works for all kinds of FPGAs. For Xilinx FPGAs, we demonstrate in detail that we can integrate the watermarking algorithms and the signature into the functionality of the watermarked core. So it is very hard to remove the watermark without destroying the core. Furthermore, we introduce a detection algorithm which can decode the signature from a voltage trace with high reliability. Additionally, two enhanced robustness algorithms are introduced which improve the detection probability in case of considerable noise sources. Using these techniques, it is possible to decode the signature even if other cores operate on the same device at the same time.