# K2: A STREAM CIPHER ALGORITHM USING DYNAMIC FEEDBACK CONTROL

### Shinsaku Kiyomoto, Toshiaki Tanaka, Kouichi Sakurai

#### Abstract

A variety of different clock-controlled stream ciphers and attacks on them have been described in a number of papers. However, few word-oriented algorithms with an irregular clocking mechanism have been proposed. This paper proposes a new design of irregular clocking for word-oriented stream ciphers that is dynamic feedback control and show analysis results of its security and performance. The stream cipher K2 v2.0 is a secure and high-performance stream cipher using the dynamic feedback control, which is applicable for several applications. We believe that the dynamic feedback control mechanism is potentially effective against several different types of attacks, not only existing attacks but also novel attacks.

#### References

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#### Paper Citation

#### in Harvard Style

Kiyomoto S., Tanaka T. and Sakurai K. (2007). **K2: A STREAM CIPHER ALGORITHM USING DYNAMIC FEEDBACK CONTROL** . In *Proceedings of the Second International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2007)* ISBN 978-989-8111-12-8, pages 204-213. DOI: 10.5220/0002122302040213

#### in Bibtex Style

@conference{secrypt07,

author={Shinsaku Kiyomoto and Toshiaki Tanaka and Kouichi Sakurai},

title={K2: A STREAM CIPHER ALGORITHM USING DYNAMIC FEEDBACK CONTROL},

booktitle={Proceedings of the Second International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2007)},

year={2007},

pages={204-213},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0002122302040213},

isbn={978-989-8111-12-8},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the Second International Conference on Security and Cryptography - Volume 1: SECRYPT, (ICETE 2007)

TI - K2: A STREAM CIPHER ALGORITHM USING DYNAMIC FEEDBACK CONTROL

SN - 978-989-8111-12-8

AU - Kiyomoto S.

AU - Tanaka T.

AU - Sakurai K.

PY - 2007

SP - 204

EP - 213

DO - 10.5220/0002122302040213