“…First, practical implementations of this structure have been demonstrated on both ASICs and FPGA [16], [12]. Second, a number of researchers employed this structure for real-life applications, e.g., smart cards, RFID security and privacy, and remote IC activation [11], [9], [26], [1], [5], [22], [2]. Third, the concept can be implemented in pure digital structures and thus, it is easily realizable on FPGAs.…”