22,398 research outputs found
Symmetric blind information reconciliation and hash-function-based verification for quantum key distribution
We consider an information reconciliation protocol for quantum key
distribution (QKD). In order to correct down the error rate, we suggest a
method, which is based on symmetric blind information reconciliation for the
low-density parity-check (LDPC) codes. We develop a subsequent verification
protocol with the use of -universal hash functions, which allows
verifying the identity between the keys with a certain probability.Comment: 4 pages; 1 figure; published versio
Analysis of the Security of BB84 by Model Checking
Quantum Cryptography or Quantum key distribution (QKD) is a technique that
allows the secure distribution of a bit string, used as key in cryptographic
protocols. When it was noted that quantum computers could break public key
cryptosystems based on number theory extensive studies have been undertaken on
QKD. Based on quantum mechanics, QKD offers unconditionally secure
communication. Now, the progress of research in this field allows the
anticipation of QKD to be available outside of laboratories within the next few
years. Efforts are made to improve the performance and reliability of the
implemented technologies. But several challenges remain despite this big
progress. The task of how to test the apparatuses of QKD For example did not
yet receive enough attention. These devises become complex and demand a big
verification effort. In this paper we are interested in an approach based on
the technique of probabilistic model checking for studying quantum information.
Precisely, we use the PRISM tool to analyze the security of BB84 protocol and
we are focused on the specific security property of eavesdropping detection. We
show that this property is affected by the parameters of quantum channel and
the power of eavesdropper.Comment: 12 Pages, IJNS
Symbolic Abstractions for Quantum Protocol Verification
Quantum protocols such as the BB84 Quantum Key Distribution protocol exchange
qubits to achieve information-theoretic security guarantees. Many variants
thereof were proposed, some of them being already deployed. Existing security
proofs in that field are mostly tedious, error-prone pen-and-paper proofs of
the core protocol only that rarely account for other crucial components such as
authentication. This calls for formal and automated verification techniques
that exhaustively explore all possible intruder behaviors and that scale well.
The symbolic approach offers rigorous, mathematical frameworks and automated
tools to analyze security protocols. Based on well-designed abstractions, it
has allowed for large-scale formal analyses of real-life protocols such as TLS
1.3 and mobile telephony protocols. Hence a natural question is: Can we use
this successful line of work to analyze quantum protocols? This paper proposes
a first positive answer and motivates further research on this unexplored path
Toward Automatic Verification of Quantum Cryptographic Protocols.
Several quantum process algebras have been proposed and successfully applied
in verification of quantum cryptographic protocols. All of the bisimulations
proposed so far for quantum processes in these process algebras are
state-based, implying that they only compare individual quantum states, but not
a combination of them. This paper remedies this problem by introducing a novel
notion of distribution-based bisimulation for quantum processes. We further
propose an approximate version of this bisimulation that enables us to prove
more sophisticated security properties of quantum protocols which cannot be
verified using the previous bisimulations. In particular, we prove that the
quantum key distribution protocol BB84 is sound and (asymptotically) secure
against the intercept-resend attacks by showing that the BB84 protocol, when
executed with such an attacker concurrently, is approximately bisimilar to an
ideal protocol, whose soundness and security are obviously guaranteed, with at
most an exponentially decreasing gap.Comment: Accepted by Concur'1
On single-photon quantum key distribution in the presence of loss
We investigate two-way and one-way single-photon quantum key distribution
(QKD) protocols in the presence of loss introduced by the quantum channel. Our
analysis is based on a simple precondition for secure QKD in each case. In
particular, the legitimate users need to prove that there exists no separable
state (in the case of two-way QKD), or that there exists no quantum state
having a symmetric extension (one-way QKD), that is compatible with the
available measurements results. We show that both criteria can be formulated as
a convex optimisation problem known as a semidefinite program, which can be
efficiently solved. Moreover, we prove that the solution to the dual
optimisation corresponds to the evaluation of an optimal witness operator that
belongs to the minimal verification set of them for the given two-way (or
one-way) QKD protocol. A positive expectation value of this optimal witness
operator states that no secret key can be distilled from the available
measurements results. We apply such analysis to several well-known
single-photon QKD protocols under losses.Comment: 14 pages, 6 figure
Secure and efficient decoy-state quantum key distribution with inexact pulse intensities
We present a general theorem for the efficient verification of the lower
bound of single-photon transmittance. We show how to do decoy-state quantum key
distribution efficiently with large random errors in the intensity control. In
our protocol, the linear terms of fluctuation disappear and only the quadratic
terms take effect. We then show the unconditional security of decoy-state
method with whatever error pattern in intensities of decoy pulses and signal
pulses provided that the intensity of each decoy pulse is less than and
the intensity of each signal pulse is larger than
- …