Sosemanuk is a new synchronous software-oriented stream cipher, corresponding to Profile 1 of the ECRYPT call for stream cipher primitives. Its key length is variable between 128 and 256 bits. It accommodates a 128-bit initial value. Any key length is claimed to achieve 128-bit security. The Sosemanuk cipher uses both some basic design principles from the stream cipher SNOW 2.0 and some transfo...

Although a number of block ciphers have been designed and are available in the public domain, they are usually used in one of the four modes: the cipher block chaining mode, the cipher feedback mode, the output feedback mode, and the counter mode. In all these cases, a stream cipher is actually used, as any block cipher used in any of these modes becomes a stream cipher. Stream ciphers are pref...

In this document we specify and motivate the hardware-oriented self-synchronizing stream cipher Mosquito and the underlying cipher architecture and provide hardware implementation results. This stream cipher is a close variant of the cipher ΥΓ, described in [2]. ΥΓ in its turn was a corrected version of the cipher KNOT published in [1], removing the weaknesses that have lead to its breaking in ...

In this paper, we use a high-order iterated function generated by block cipher as the nonlinear filter to improve the security of stream cipher. Moreover, by combining the published rounds function in block cipher and OFB as the nonlinear functional mode with an extra memory module, we enable to control the nonlinear complexity of the design. This new approach fuses the block cipher operation m...

The present paper deals with the problem of identification among English, romanized Hindi & Punjabi language directly from its plain bit stream. A novice feature extraction technique namely BTR has been discussed & the description of each feature component has been highlighted. An attempt has also been made to identify above-mentioned languages from their cipher bit stream obtained through a bl...

In this paper, we show several known-plaintext attacks on the stream cipher HBB which was proposed recently at INDOCRYPT 2003. The cipher can operate either as a classical stream cipher in the “B mode” or as an asynchronous stream cipher in the “SS mode”. In the case of the SS mode, we present known-plaintext attacks recovering 128-bit key with the complexity 2 and 256-bit key with the complexi...

RAKAPOSHI is a hardware oriented stream cipher designed by Carlos Cid et al. in 2009. The stream cipher is based on Dynamic Linear Feedback Shift Registers, with a simple and potentially scalable design, and is particularly suitable for hardware applications with restricted resources. The RAKAPOSHI stream cipher offers 128-bit security. In this paper, we point out some weaknesses in the cipher....

Pseudo-random number generators (PRNGs) are a key component of stream ciphers used for encryption purposes. While Non linear Feedback Shift Registers (NFSRs) combined with cellular automata has been utilized for PRNGs, the use of cellular automata (CA) is another viable option. This paper explores the combination of NFSRs and CA as the key components of an efficient stream cipher design for imp...