• Journal of Digital Convergence
• /
• v.11 no.11
• /
• pp.389-395
• /
• 2013

As fusing IT and medical technique, the number of patients who adhere medical equipment inside of them is increasing. However there is a problem of for the third person to tap or modulate the patient's biometric data viciously. This paper suggests quantum encryption-based key distribution model to share key for the third person not to tap or modulate the patient's biometric data between patient and hospital staff. The proposed model uses one-time pad key that shares key sending random bits not direct sending message of quantum data. Also, it guarantees patient's anonymity because the biometric data of injected-device in the body doesn't be exposed unnecessarily.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.30 no.5
• /
• pp.771-780
• /
• 2020

QKD(Quantum Key Distribution) is one of the protocols that can make two distant parties safely share secure keys against the threat of quantum computer. Generally, cryptographic applications which are connected to the QKD device have fixed roles as a transmitter and a receiver due to the race condition and complexity of implementation. Because the conventional QKD system is mainly applied to the link encryptor, there are no problems even if the roles of the cryptographic devices are fixed. We propose a new scheme of QKD system and protocol that is easy to extend to the QKD network by eliminating quantum key dependency between cryptographic device and QKD node. The secure keys which are generated by the TRNG(True Random Number Generator) are provided to the cryptographic applications instead of quantum keys. We design an architecture to transmit safely the secure keys using the inbound and outbound quantum keys which are shared between two nodes. In this scheme, since the dependency of shared quantum keys between two QKD nodes is eliminated, all cryptographic applicatons can be a master or a slave depending on who initiates the cryptographic communications.

• ETRI Journal
• /
• v.45 no.3
• /
• pp.462-478
• /
• 2023

In quantum computing, the use of Pauli frames through software traces of classical computers improves computation efficiency. In previous studies, error correction and Pauli operation tracking have been performed simultaneously using integrated Pauli frames in the physical layer. In such a complex processing structure, the number of simultaneous operations processed in the physical layer exponentially increases as the distance of the surface code encoding logical qubit increases. This study proposes a Pauli frame management architecture partitioned into two layers for a lattice surgery-based surface code and describes its structure and operation rules. To evaluate the effectiveness of our method, we generated a random circuit according to the gate ratios constituting the commonly known quantum circuits and compared the generated circuit with the existing Pauli frame and our method. Simulations show a decrease of about 5% over traditional methods. In the case of experiments that only increase the code distance of the logical qubit, it can be seen that the effect of reducing the physical operation through the logical Pauli frame becomes more important.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.10
• /
• pp.5190-5208
• /
• 2016

Because of the advantages of certificateless and no escrow feature over the regular signature and identity-based signature, certificateless signature has been widely applied in e-business, e-government and software security since it was proposed in 2003. Although a number of certificateless signature schemes have been proposed, there is only one lattice-based certificateless signature scheme which is still secure in the quantum era. But its efficiency is not very satisfactory. In this paper, the first certificateless signature scheme on NTRU lattice is proposed, which is proven to be secure in random oracle model. Moreover, the efficiency of the new scheme is higher than that of the only one lattice-based certificateless signature.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.18 no.4
• /
• pp.73-78
• /
• 2018

In this paper, we consider a system where multiple sources are encrypted in separated nodes and sent through their respective public communication channels into a joint sink node. We are interested at the problem on protecting the security of an already existing system such above, which is found out to have correlated encryption keys. In particular, we focus on finding a solution without introducing additional secret keys and with minimal modification to minimize the cost and the risk of bringing down an already running system. We propose a solution under a security model where an eavesdropper obtains all ciphertexts, i.e., encrypted sources, by accessing available public communication channels. Our main technique is to use encoders of universal function to encode the ciphertexts before sending them to public communication channels.

• Journal of Astronomy and Space Sciences
• /
• v.36 no.1
• /
• pp.21-33
• /
• 2019

This paper focuses on the interpretation of radiation fluxes from active galactic nuclei. The advantage of positron annihilation spectroscopy over other methods of spectral diagnostics of active galactic nuclei (therefore AGN) is demonstrated. A relationship between regular and random components in both bolometric and spectral composition of fluxes of quanta and particles generated in AGN is found. We consider their diffuse component separately and also detect radiative feedback after the passage of high-velocity cosmic rays and hard quanta through gas-and-dust aggregates surrounding massive black holes in AGN. The motion of relativistic positrons and electrons in such complex systems produces secondary radiation throughout the whole investigated region of active galactic nuclei in form of cylinder with radius R= 400-1000 pc and height H=200-400 pc, thus causing their visible luminescence across all spectral bands. We obtain radiation and electron energy distribution functions depending on the spatial distribution of the investigated bulk of matter in AGN. Radiation luminescence of the non-central part of AGN is a response to the effects of particles and quanta falling from its center created by atoms, molecules and dust of its diffuse component. The cross-sections for the single-photon annihilation of positrons of different energies with atoms in these active galactic nuclei are determined. For the first time we use the data on the change in chemical composition due to spallation reactions induced by high-energy particles. We establish or define more accurately how the energies of the incident positron, emitted ${\gamma}-quantum$ and recoiling nucleus correlate with the atomic number and weight of the target nucleus. For light elements, we provide detailed tables of all indicated parameters. A new criterion is proposed, based on the use of the ratio of the fluxes of ${\gamma}-quanta$ formed in one- and two-photon annihilation of positrons in a diffuse medium. It is concluded that, as is the case in young supernova remnants, the two-photon annihilation tends to occur in solid-state grains as a result of active loss of kinetic energy of positrons due to ionisation down to thermal energy of free electrons. The single-photon annihilation of positrons manifests itself in the gas component of active galactic nuclei. Such annihilation occurs as interaction between positrons and K-shell electrons; hence, it is suitable for identification of the chemical state of substances comprising the gas component of the investigated media. Specific physical media producing high fluxes of positrons are discussed; it allowed a significant reduction in the number of reaction channels generating positrons. We estimate the brightness distribution in the ${\gamma}-ray$ spectra of the gas-and-dust media through which positron fluxes travel with the energy range similar to that recorded by the Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics (PAMELA) research module. Based on the results of our calculations, we analyse the reasons for such a high power of positrons to penetrate through gas-and-dust aggregates. The energy loss of positrons by ionisation is compared to the production of secondary positrons by high-energy cosmic rays in order to determine the depth of their penetration into gas-and-dust aggregations clustered in active galactic nuclei. The relationship between the energy of ${\gamma}-quanta$ emitted upon the single-photon annihilation and the energy of incident electrons is established. The obtained cross sections for positron interactions with bound electrons of the diffuse component of the non-central, peripheral AGN regions allowed us to obtain new spectroscopic characteristics of the atoms involved in single-photon annihilation.