# Deterministic Cryptanalysis of some Stream Ciphers

### P. Caballero-Gil, A. Fúster-Sabater, C. Hernández-Goya

#### Abstract

A new graph-based approach to edit distance cryptanalysis of some clock-controlled generators is here presented in order to simplify search trees of the original attacks. In particular, the proposed improvement is based on cut sets defined on some graphs so that only the most promising branches of the search tree have to be analyzed because certain shortest paths provide the edit distances. The strongest aspects of the proposal are: a) the obtained results from the attack are absolutely deterministic and b) many inconsistent initial states are recognized beforehand and avoided during search.

#### References

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#### Paper Citation

#### in Harvard Style

Caballero-Gil P., Fúster-Sabater A. and Hernández-Goya C. (2009). **Deterministic Cryptanalysis of some Stream Ciphers** . In *Proceedings of the 7th International Workshop on Security in Information Systems - Volume 1: WOSIS, (ICEIS 2009)* ISBN 978-989-8111-91-3, pages 16-25. DOI: 10.5220/0002175500160025

#### in Bibtex Style

@conference{wosis09,

author={P. Caballero-Gil and A. Fúster-Sabater and C. Hernández-Goya},

title={Deterministic Cryptanalysis of some Stream Ciphers},

booktitle={Proceedings of the 7th International Workshop on Security in Information Systems - Volume 1: WOSIS, (ICEIS 2009)},

year={2009},

pages={16-25},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0002175500160025},

isbn={978-989-8111-91-3},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 7th International Workshop on Security in Information Systems - Volume 1: WOSIS, (ICEIS 2009)

TI - Deterministic Cryptanalysis of some Stream Ciphers

SN - 978-989-8111-91-3

AU - Caballero-Gil P.

AU - Fúster-Sabater A.

AU - Hernández-Goya C.

PY - 2009

SP - 16

EP - 25

DO - 10.5220/0002175500160025