Finding Matching Initial States for Equivalent NLFSRs in the Fibonacci and the Galois Configurations

Author

Dubrova, Elena

Author_Institution

ECS/ICT/KTH, R. Inst. of Technol. (KTH), Stockholm, Sweden

Volume

56

Issue

6

fYear

2010

fDate

6/1/2010 12:00:00 AM

Firstpage

2961

Lastpage

2966

Abstract

The Fibonacci and the Galois configurations of nonlinear feedback shift registers (NLFSRs) are considered. In the former, the feedback is applied to the input bit of the shift register only. In the latter, the feedback can potentially be applied to every bit. The sufficient conditions for equivalence of NLFSRs in the Fibonacci and the Galois configurations have been formulated previously. The equivalent NLFSRs in different configurations normally have to be initialized to different states to generate the same output sequences. The mapping between the initial states of two equivalent NLFSRs in the Fibonacci and the Galois configurations is derived in this paper.

Keywords

Fibonacci sequences; binary sequences; feedback; Fibonacci configuration; Galois configuration; equivalent NLFSR; initial states matching; nonlinear feedback shift register; Cryptography; Feedback circuits; Linear feedback shift registers; Performance evaluation; Random sequences; Shift registers; State feedback; Sufficient conditions; Testing; Throughput; Fibonacci nonlinear feedback shift register (NLFSR); Galois NLFSR; initial state; pseudorandom sequence; stream cipher;

fLanguage

English

Journal_Title

Information Theory, IEEE Transactions on

Publisher

ieee

ISSN

0018-9448

Type

jour

DOI

10.1109/TIT.2010.2046250

Filename

5466519