# A Complete Divide and Conquer Attack on the Alpha1 Stream Cipher

@inproceedings{Chen2003ACD, title={A Complete Divide and Conquer Attack on the Alpha1 Stream Cipher}, author={Kevin Chen and Leonie Ruth Simpson and Matt Henricksen and William Millan and Ed Dawson}, booktitle={ICISC}, year={2003} }

Alpha1 is a stream cipher with a key size of 128 bits. It was proposed as a replacement algorithm for the stream cipher A5 to supply confidentiality over mobile communication systems. Alpha1 consists of four binary linear feedback shift registers. Previous attacks on Alpha1 only recover the initial state of the shortest register. In this paper we present a complete divide and conquer attack, starting with an improved attack on the shortest register, and continuing the attack to recover the…

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## 4 Citations

Algebraic Attacks on Clock-Controlled Stream Ciphers

- Computer Science, MathematicsACISP
- 2006

An algebraic attack approach to a family of irregularly clock-controlled bit-based linear feedback shift register systems is presented and it is demonstrated that the degree of a functional relationship between the registers can be bounded by two.

Mutually Clock-Controlled Feedback Shift Registers Provide Resistance to Algebraic Attacks

- Computer Science, MathematicsInscrypt
- 2007

It is shown that, if there are no regularly clocked shift registers included in the system, mutually clock-controlled feedback shift register ciphers appear to be highly resistant to algebraic attacks.

Experimental Analysis of Guess-and-Determine Attacks on Clock-Controlled Stream Ciphers

- Computer Science, MathematicsIEICE Trans. Fundam. Electron. Commun. Comput. Sci.
- 2005

This paper discusses GD attacks on clock-controlled stream ciphers, which use irregular clocking for a non-linear function, and proposes and calculates the process complexity of these attacks.

Cryptanalysis Techniques for Stream Cipher: A Survey

- Computer Science, Mathematics
- 2012

This study aims to provide a comprehensive survey that summarizes the existing cryptanalysis techniques for stream ciphers and will facilitate the security analysis of the existing stream cipher designs and provide an opportunity to understand the requirements for developing a secure and efficient stream cipher design.

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