This paper tackles the issue of single relay selection for secure communication in a fullduplex regenerative cooperative system under attack of an eavesdropper. We propose a novel single relay selection scheme, which does not requires the instantaneous channel state information of wiretap channels, to enhance the system security level. Through simulations, we show that the proposed scheme gives...

In this work we present a quantum key distribution protocol using continuous-variable nonGaussian states, homodyne detection and post-selection. The employed signal states are the Photon Added then Subtracted Coherent States (PASCS) in which one photon is added and subsequently one photon is subtracted. We analyze the performance of our protocol, compared to a coherent state based protocol, for...

We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the correspondi...

Cryptographic identification protocols enable a prover to prove its identity to a verifier. A subclass of such protocols are shared-secret challenge-response identification protocols in which the prover and the verifier share the same secret and the prover has to respond to a series of challenges from the verifier. When the prover is a human, as opposed to a machine, such protocols are called h...

In this paper, we study the design of secure communication for time division duplexing multi-cell multi-user massive multiple-input multiple-output (MIMO) systems with active eavesdropping. We assume that the eavesdropper actively attacks the uplink pilot transmission and the uplink data transmission before eavesdropping the downlink data transmission phase of the desired users. We exploit both...

We extend earlier research on mounting and resisting passive long-term end-to-end traffic analysis attacks against anonymous message systems, by describing how an eavesdropper can learn sender-receiver connections even when the substrate is a network of pool mixes, the attacker is non-global, and senders have complex behavior or generate padding messages. Additionally, we describe how an attack...

In this paper, we propose a novel secure transmission scheme for MIMO Two-Way Relay Channels. By exploiting the properties of the transmission medium in the physical layer, our proposed scheme could achieve a high transmission efficiency as well as security. Two different approaches has been introduced including Information Theoretical approach and Physical Layer Encryption approach. Direction ...

The ability of an eavesdropper to compromise the security a quantum communication system by changing angle incoming light is well-known. Randomizing role detectors has been proposed be efficient countermeasure this type attack. Here we show that can bypassed if attack generalized including more variables. Using experimental data from existing literature, how randomization effectively prevents i...

It has been found that an algorithm can generate true random numbers on classical computer. The algorithm can be used to generate unbreakable message PIN (personal identification number) and password. Cryptography has long history [1]. Interestingly, it has been found that taking key material from open source it is possible to design unbreakable crypto-system. Following the technique [2] an alg...

Distinguishability of photons in non-operational degrees freedom compromises unconditional security quantum key distribution since an eavesdropper can improve attack strategies by exploiting this distinguishability. However, the optimal eavesdropping presence light source side channels are not known. Here we provide several explicit on BB84 protocol with partially distinguishable photons. In pa...