Combining Certain Nonlinear Feedback Shift Registers
نویسندگان
چکیده
Stream ciphers that deploy linear feedback shift registers (LFSRs) have been shown to be vulnerable under fast correlation attacks [20], [21], [14], algebraic attacks [7], [28], fast algebraic attacks [6], [1], and fault attacks [13]. We discuss certain nonlinear feedback shift registers (NLFSRs) recommended as substitutes for LFSRs in stream cipher systems.
منابع مشابه
Investigation of FCSR-based Pseudorandom Sequence Generators for Stream Ciphers
In this paper, feedback with carry shift registers (FCSRs) are analyzed with main focus on the general case of FCSRs with arbitrary connection integer and on maximum-period FCSRs. Moreover, a keystream generator that employs the structure of the linear feedback shift register (LFSR)-based Geffegenerator is studied in connection with FCSRs as a special nonlinear combining generator. The consider...
متن کاملSimple power analysis applied to nonlinear feedback shift registers
Linear feedback shift registers (LFSRs) and nonlinear feedback shift registers (NLFSRs) are major components of stream ciphers. It has been shown that, under certain idealized assumptions, LFSRs and LFSR-based stream ciphers are susceptible to cryptanalysis using simple power analysis (SPA). In this paper, we show that simple power analysis can be practically applied to a CMOS digital hardware ...
متن کاملPeriods on Two Kinds of nonlinear Feedback Shift Registers with Time Varying Feedback Functions
Grain and Trivium are the hardware-oriented finalists of the eSTREAM. They are both based on nonlinear feedback shift registers. In this paper, we study their generalized classes of nonlinear feedback shift registers with time varying feedback functions, namely, Grain-like and Trivium-like structures. Some interesting results regarding their periods are obtained.
متن کاملOn Feedback Functions of Maximum Length Nonlinear Feedback Shift Registers
Feedback shift registers are basic building blocks for many cryptographic primitives. Due to the insecurities of Linear Feedback Shift Register (LFSR) based systems, the use of Nonlinear Feedback Shift Registers (NFSRs) became more popular. In this work, we study the feedback functions of NFSRs with period 2n. First, we provide two new necessary conditions for feedback functions to be maximum l...
متن کاملAlgebraic Feedback Shift Registers
A general framework for the design of feedback registers based on algebra over complete rings is described. These registers generalize linear feedback shift registers and feedback with carry shift registers. Basic properties of the output sequences are studied: relations to the algebra of the underlying ring; synthesis of the register from the sequence (which has implications for cryptanalysis)...
متن کامل