Some Unexplored State sequences of Linear Feedback Shift Registers
M. Sivasankar, G. Prema · 2013
With the limitation of having only φ(2 n −1) n primitive polynomials of degree n over F2, any primitive Linear Feedback Shift Register with n stages can visit the (2 n − 1) non-zero n-bit states in φ(2 n −1) n ways only. Infact it is obvious that there are (2 n −1)! possible ways of visiting these (2 n − 1) n-bit strings. In this paper, we attempt to visit all or part of these (2 n − 1) n-bit strings in some other order using irreducible non-primitive polynomials. The security of the key bit streams hence generated is also analysed.