Nlfsr

NLFSR

A NLFSR (Non-Linear Feedback Shift Register) is a common component in modern stream ciphers, especially in RFID and smartcard applications. NLFSRs are known to be more resistant to cryptanalytic attacks than Linear Feedback Shift Registers (LFSRs), although construction of large NLFSRs with guaranteed long periods remains an open problem. However, with bruteforce methods, a list of maximum-period n-bit NLFSRs for n < 25 has been found as well as for n=25 and n=27