Home OALib Journal OALib PrePrints Submit Ranking News My Lib FAQ About Us Follow Us+
 Title Keywords Abstract Author All
Search Results: 1 - 10 of 100 matches for " "
 Page 1 /100 Display every page 5 10 20 Item
 Physics , 2008, DOI: 10.1142/S0219749909004554 Abstract: We study eavesdropping in quantum key distribution with the six state protocol,when the signal states are mixed with white noise. This situation may arise either when Alice deliberately adds noise to the signal states before they leave her lab, or in a realistic scenario where Eve cannot replace the noisy quantum channel by a noiseless one. We find Eve's optimal mutual information with Alice, for individual attacks, as a function of the qubit error rate. Our result is that added quantum noise can make quantum key distribution more robust against eavesdropping.
 Antoni Wojcik Physics , 2002, DOI: 10.1103/PhysRevLett.90.157901 Abstract: The proposed eavesdropping scheme reveals that the quantum communication protocol recently presented by Bostrom and Felbinger [Phys. Rev. Lett. 89, 187902 (2002)] is not secure as far as quantum channel losses are taken into account.
 Computer Science , 2012, DOI: 10.1016/j.ipl.2013.03.008 Abstract: In semiquantum key-distribution (Boyer et al.) Alice has the same capability as in BB84 protocol, but Bob can measure and prepare qubits only in $\{|0\rangle, |1\rangle\}$ basis and reflect any other qubit. We study an eavesdropping strategy on this scheme that listens to the channel in both the directions. With the same level of disturbance induced in the channel, Eve can extract more information using our two-way strategy than what can be obtained by the direct application of one-way eavesdropping in BB84.
 中国物理 B , 2011, Abstract: We present an improved eavesdropping scheme on the quantum dialogue protocol in lossy channel, which is based on the strategies of Wójcik Phys. Rev. Lett. 90 157901 (2003)] and ZML Phys. Lett. A 333 46 (2004)] attack schemes. We show that our attack scheme doubles the domain of Eve's eavesdropping and Eve can gain more information of the communication with less risk of being detected. Finally, a possible improvement for the dialogue protocol security is proposed.
 中国物理 B , 2009, Abstract: We propose a quantum error-rejection scheme for direct communication with three-qubit quantum codes based on the direct communication of secret messages without any secret key shared in advance. Given the symmetric and independent errors of the transmitted qubits, our scheme can tolerate a bit of error rate up to 33.1%, thus the protocol is deterministically secure against any eavesdropping attack even in a noisy channel.
 Physics , 2004, DOI: 10.1016/j.physleta.2005.05.023 Abstract: The eavesdropping scheme proposed by W\'{o}jcik [Phys. Rev. Lett. {\bf 90},157901(2003)] on the ping-pong protocol [Phys. Rev. Lett. {\bf 89}, 187902(2002)] is improved by constituting a new set of attack operations. The improved scheme has a zero eavesdropping-induced channel loss and produces perfect anticorrelation. Therefore, the eavesdropper Eve can safely attack all the transmitted bits and the eavesdropping information gain can always exceed the legitimate user's information gain in the whole domain of the quantum channel transmission efficiency $\eta$, i.e., [0,100%]. This means that the ping-pong protocol can be completely eavesdropped in its original version. But the improvement of the ping-pong protocol security produced by W\'{o}jcik is also suitable for our eavesdropping attack.
 Qing-yu Cai Physics , 2004, DOI: 10.1103/PhysRevLett.91.109801 Abstract: Attack the ping-pong protocol without eavesdropping.
 中国物理 B , 2007, Abstract: We introduce an attack scheme for eavesdropping freely the ping-pong quantum communication protocol proposed by Bostr\"{o} m and Felbinger Phys. Rev. Lett. 89, 187902 (2002)] in a noise channel. The vicious eavesdropper, Eve, intercepts and measures the travel photon transmitted between the sender and the receiver. Then she replaces the quantum signal with a multi-photon signal in the same state, and measures the returned photons with the measuring basis, with which Eve prepares the fake signal except for one photon. This attack increases neither the quantum channel losses nor the error rate in the sampling instances for eavesdropping check. It works for eavesdropping the secret message transmitted with the ping-pong protocol. Finally, we propose a way for improving the security of the ping-pong protocol.
 Physics , 2005, Abstract: We thoroughly analyse the novel quantum key distribution protocol introduced recently in quant-ph/0412075, which is based on minimal qubit tomography. We examine the efficiency of the protocol for a whole range of noise parameters and present a general analysis of incoherent eavesdropping attacks with arbitrarily many steps in the iterative key generation process. The comparison with the tomographic 6-state protocol shows that our protocol has a higher efficiency (up to 20%) and ensures the security of the established key even for noise parameters far beyond the 6-state protocol's noise threshold.
 Physics , 2005, DOI: 10.1088/1009-1963/16/2/001 Abstract: We introduce an attack scheme for eavesdropping the ping-pong quantum communication protocol proposed by Bostr$\ddot{o}$m and Felbinger [Phys. Rev. Lett. \textbf{89}, 187902 (2002)] freely in a noise channel. The vicious eavesdropper, Eve, intercepts and measures the travel photon transmitted between the sender and the receiver. Then she replaces the quantum signal with a multi-photon signal in a same state, and measures the photons return with the measuring basis with which Eve prepares the fake signal except for one photon. This attack increase neither the quantum channel losses nor the error rate in the sampling instances for eavesdropping check. It works for eavesdropping the secret message transmitted with the ping-pong protocol. Finally, we propose a way for improving the security of the ping-pong protocol.
 Page 1 /100 Display every page 5 10 20 Item