The sequential circuit designed was Look-Ahead Transformation based LFSR in which a hardware complexity was present and it may limit their employ in many applications. The design of efficient LFSR for BCH encoder using TePLAT (Term Preserving Look-Ahead Transformation) overcame this limitation by opening the employ of minimizing the iteration bound and hardware complexity in wide range of appli...

– A built–in Test Pattern Generation (TPG) mechanism that is very popular for pseudorandom or pseudo–exhaustive TPG is a shift register whose initial portion is configured as a Linear Feedback Shift Register (LFSR), or some other kind of a Linear Finite State Machine (LFSM). A fundamental problem that exists in this mechanism is the presence of linear dependencies among the bit sequences produc...

Coppersmith, Krawczyk, and Mansour ([CKM93]) presented at Crypto '93 a promising stream cipher, the shrinking generator. It is based on linear shift registers with linear feedback. The output bits of one shift register decide which of the output bits of the other shift registers are used and which are discarded. The design is well suited for hardware implementation. In software shift registers ...

A new fault coverage test pattern generator using a linear feedback shift register (LFSR) called FC-LFSR can perform fault analysis and reduce the power of a circuit during test by generating three intermediate patterns between the random patterns by reducing the hardware utilization. The goal of having intermediate patterns is to reduce the transitional activities of Primary Inputs (PI) which ...

Filter generators are vulnerable to several attacks which have led to well-known design criteria on the Boolean filtering function. However, Rønjom and Cid have observed that a change of the primitive root defining the LFSR leads to several equivalent generators. They usually offer different security levels since they involve filtering functions of the form F (x) where k is coprime to (2 − 1) a...

We present a new cryptanalytic attack on PN-generators filtered by a Boolean function. The key-idea is to jointly combine the knowledge of the Boolean function and the LFSR structure so as to introduce a new iterative decoding technique. The results we obtained prove to be very good: indeed, even in the case of systems for which classical iterative algorithms appear powerless, our scheme enable...

A new hybrid BIST scheme is proposed which is based on using an “incrementally guided LFSR.” It very efficiently combines external deterministic data from the tester with on-chip pseudo-random BIST. The hardware overhead is very small as a conventional STUMPS architecture [1] is used with only a small modification to the feedback of the LFSR which allows the tester to incrementally guide the LF...

This paper describes new methods for fast correlation attacks, based on the theory of convolutional codes. They can be applied to arbitrary LFSR feedback polynomials, in opposite to the previous methods, which mainly focus on feedback polynomials of low weight. The results improve significantly the few previous results for this general case, and are in many cases comparable with corresponding r...

Algebraic attacks on stream ciphers apply (at least theoretically) to all LFSR-based stream ciphers that are clocked in a simple and/or easily predictable way. One interesting approach to help resist such attacks is to add a component that de-synchronizes the output bits of the cipher from the clock of the LFSR. The Bit-search generator, recently proposed by Gouget and Sibert, is inspired by th...