MUGI [15] is a word-based stream cipher designed for 64bit architectures. It uses a 128-bit master key and a 128-bit initialization vector to populate a large non-linear feedback shift register (NLFSR) and additional non-linear state (NLS). In standard benchmarks on 32-bit processors, MUGI suffers from poor key agility because it is implemented on an architecture for which it is not designed, a...

Most of the lightweight block ciphers are nibble-oriented as the implementation of a 4-bit S-box is much more compact than an 8-bit S-box. This paper proposes a novel implementation of multiplicative inverse for 8-bit S-boxes using LFSR requiring only 138 gate-equivalent. It can be shown that if such S-boxes are adopted for the AES it takes less than 50 gate-equivalent per S-box in parallel imp...

This paper presents the design of a lightweight, yet software friendly, block cipher. Most of the lightweight block ciphers are nibbleoriented as the implementation of a 4-bit S-box is much more compact than an 8-bit S-box. This paper uses a novel implementation of multiplicative inverse for 8-bit S-boxes using LFSR requiring only 138 gateequivalent. With this powerful scheme, we design a light...

We study algebraic feedback shift registers (AFSRs) based on quotients of polynomial rings in several variables over a finite field. These registers are natural generalizations of linear feedback shift registers. We describe conditions under which such AFSRs produce sequences with various ideal randomness properties. We also show that there is an efficient algorithm which, given a prefix of a s...

Anewsoftware-baseddtestvectorcompressionn technique is proposedd for usingg ann embeddedd processor too test the other components of aa system-on-a-chipp (SOC). The tester transfers compressedd test dataa too the processor's on-chipp memory, andd the processor executes aa small program whichh decompresses the dataa andd applies it too the scann chains of eachh core-under-test. The proposedd dec...

An algorithm is given for the reconstruction of the initial state of a key–stream generator (KSG) consisting of a short linear feedback shift register (length ≤ 30), whose clock is controlled by an algebraically simple internal KSG. The algorithm is based on the fact that the expected number of possible LFSR initial states exponentially decreases with the length of the known part of the output ...

Feedback with carry shift registers (FCSRs) are a class of finite state devices that are similar to linear feedback shift registers (LFSRs) in their simplicity and statistical randomness, and in that they have algebraic tools for the analysis of their output. In this paper we describe and analyze an alternative architecture for FCSRs that is similar to the Galois architecture for LFSRs. We also...

Using the structure of Singer cycles in general linear groups, we prove that a conjecture of Zeng, Han and He (2007) holds in the affirmative in a special case, and outline a plausible approach to prove it in the general case. This conjecture is about the number of primitive σ-LFSRs of a given order over a finite field, and it generalizes a known formula for the number of primitive LFSRs, which...

Recently, a new class of feedback shift registers (FCSRs) was introduced, based on algebra over the 2-adic numbers. The sequences generated by these registers have many algebraic properties similar to those generated by linear feedback shift registers. However, it appears to be significantly more difficult to find maximal period FCSR sequences. Jn this paper we exhibit a tpchnique for easily fi...

Recently, a new class of feedback shift registers (FCSRs) was introduced, based on algebra over the 2-adic numbers. The sequences generated by these registers have many algebraic properties similar to those generated by linear feedback shift registers. However, it appears to be significantly more difficult to find maximal period FCSR sequences. In this paper we exhibit a technique for easily fi...