# Security Against Collective Attacks of a Modified BB84 QKD Protocol with Information only in One Basis

### Michel Boyer, Rotem Liss, Tal Mor

#### Abstract

The Quantum Key Distribution (QKD) protocol BB84 has been proven secure against several important types of attacks: the collective attacks and the joint attacks. Here we analyze the security of a modified BB84 protocol, for which information is sent only in the z basis while testing is done in both the z and the x bases, against collective attacks. The proof follows the framework of a previous paper (Boyer et al., 2009), but it avoids the classical information-theoretical analysis that caused problems with composability. We show that this modified BB84 protocol is as secure against collective attacks as the original BB84 protocol, and that it requires more bits for testing.

#### References

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#### Paper Citation

#### in Harvard Style

Boyer M., Liss R. and Mor T. (2017). **Security Against Collective Attacks of a Modified BB84 QKD Protocol with Information only in One Basis** . In *Proceedings of the 2nd International Conference on Complexity, Future Information Systems and Risk - Volume 1: COMPLEXIS,* ISBN 978-989-758-244-8, pages 23-29. DOI: 10.5220/0006241000230029

#### in Bibtex Style

@conference{complexis17,

author={Michel Boyer and Rotem Liss and Tal Mor},

title={Security Against Collective Attacks of a Modified BB84 QKD Protocol with Information only in One Basis},

booktitle={Proceedings of the 2nd International Conference on Complexity, Future Information Systems and Risk - Volume 1: COMPLEXIS,},

year={2017},

pages={23-29},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0006241000230029},

isbn={978-989-758-244-8},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 2nd International Conference on Complexity, Future Information Systems and Risk - Volume 1: COMPLEXIS,

TI - Security Against Collective Attacks of a Modified BB84 QKD Protocol with Information only in One Basis

SN - 978-989-758-244-8

AU - Boyer M.

AU - Liss R.

AU - Mor T.

PY - 2017

SP - 23

EP - 29

DO - 10.5220/0006241000230029