E.A. Matveev – Director of «Сryptosoft» (Penza)

From the description of the cryptographic system AKM2017 it follows that the qubit carriers for the formation of key information after their use are not destroyed. The question arises: is there a principal possibility of their restoration in a state suitable for re-use?

The answer is yes. The recovery of carrier-qubit pairs for the formation of key information in the spin singlet state can be carried out remotely using an external source of pairs of entangled photons in the spin singlet state (for example, using satellites similar to those built in the Sino-European project of 2013−2017). using a procedure close to the «swapping» procedure – the transfer of entanglement. The article presents the main provisions of the protocol for restoring the states-carriers of qubits of key information for the new quantum cryptographic system AKM2017. The protocol realizes the idea of the remote formation of the spin singlet state of a two-qubit quantum system. The implementation of this protocol ensures the possibility of multiple safe use of the same key carriers. This makes it possible to increase the stability of communication in highly available systems, in which the quantum cryptographic system AKM2017 is used to protect information.

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