Quantum Inf Process (2015) 14:4237–4244
Proactive quantum secret sharing
· Yuewei Dai
Received: 24 May 2015 / Accepted: 22 August 2015 / Published online: 29 August 2015
© Springer Science+Business Media New York 2015
Abstract A proactive quantum secret sharing scheme is proposed, in which the partic-
ipants can update their key shares periodically. In an updating period, one participant
randomly generates the EPR pairs, and the other participants update their key shares
and perform the corresponding unitary operations on the particles of the EPR pairs.
Then, the participant who generated the EPR pairs performs the Bell-state measure-
ment and updates his key share according to the result of the Bell-state measurement.
After an updating period, each participant can change his key share, but the secret is
changeless, and the old key shares will be useless even if they have been stolen by
the attacker. The proactive property of our scheme is very useful to resist the mobile
Keywords Quantum secret sharing · Proactive · Bell state · Quantum cryptography
Secret sharing (SS) is an efﬁcient measure to protect the important data. In a SS
scheme, the secret is split into several parts and is kept by different participants. Then,
only the legitimate participants can cooperate to recover the original secret. Since
Shamir  proposed the ﬁrst SS scheme in 1979, SS has become an important topic
Quantum secret sharing (QSS) is the extension of classical SS in quantum cryp-
tography. In QSS, the secret is distributed and reconstructed by quantum mechanism.
Compared to the classical SS, QSS is more secure because of the excellent properties
School of Automatization, Nanjing University of Science and Technology, Nanjing 210094, China