A Galois LFSR, or a
LFSR in
Galois configuration is a variation on typical
Linear Feedback Shift Register design.
In a typical LFSR, the output is concatenated with the contents of certain registers, known as taps, to generate a new leftmost bit. In Galois configuration:
1. The output is individually XORed with each tap.
2. The output bit becomes the new leftmost bit.
Galois LFSRs are not cryptographically superior to typical LFSRs. They do, however, exhibit some of the same characteristics. If they are constructed from primative polynominals, they have maximal period, 2length-1 iterations before repeating. In software, Galois LFSRs exploit parallelism, and thus execute more rapidly.
Cryptology