Security in SRAM FPGAs

As FPGAs have grown larger and more complex, the value of the IP implemented in them has grown commensurately. Since SRAM FPGAs reload their programming data every time they are powered up, an adversary can potentially copy the program as it is being loaded. FPGA manufacturers have added security features to protect designs from unauthorized copy, theft, and reverse-engineering as the bitstream is transmitted from permanent storage into the FPGA. These bitstream security features use well-known information security methods to protect design data. In this discussion, it is assumed that an adversary has physical access to the FPGA. In this environment, denial-of-service attacks on the configuration are irrelevant: A trivial denial-of-service method would be to physically damage the device - the so-called "whack-it-with-a-hammer" attack.