Key Distribution Scheme Research Articles

A hierarchical key pre‐distribution scheme for fog networks

SummarySecurity in fog computing is multi‐faceted, and one particular challenge is establishing a secure communication channel between fog nodes and end devices. This emphasizes the importance of designing efficient and secret key distribution scheme to facilitate fog nodes and end devices to establish secure communication channels. Existing secure key distribution schemes designed for hierarchical networks may be deployable in fog computing, but they incur high computational and communication overheads and thus consume significant memory. In this paper, we propose a novel hierarchical key pre‐distribution scheme based on “Residual Design” for fog networks. The proposed key distribution scheme is designed to minimize storage overhead and memory consumption while increasing network scalability. The scheme is also designed to be secure against node capture attacks. We also demonstrate that, in an equal‐size network, our scheme reduces node storage overhead significantly. Our research paves the way for building an efficient key management framework for secure communication within the hierarchical network of fog nodes and end devices.

An Efficient Key Distribution Scheme in Wireless Sensor Architecture with Arduino and XBee

An Efficient Key Distribution Scheme in Wireless Sensor Architecture with Arduino and XBee

Quantum key distribution with phase-encoded coherent states: Asymptotic security analysis in thermal-loss channels

We consider discrete-alphabet encoding schemes for coherent-state quantum key distribution. The sender encodes the letters of a finite-size alphabet into coherent states whose amplitudes are symmetrically distributed on a circle centered in the origin of the phase space. We study the asymptotic performance of this phase-encoded coherent-state protocol in direct and reverse reconciliation assuming both loss and thermal noise in the communication channel. In particular, we show that using just four phase-shifted coherent states is sufficient for generating secret key rates of the order of $4 \times 10^{-3}$ bits per channel use at about 15 dB loss in the presence of realistic excess noise.

High-order encoding schemes for floodlight quantum key distribution

Floodlight quantum key distribution (FL-QKD) has realized a 1.3\,Gbit/s secret-key rate (SKR) over a 10-dB-loss channel against a frequency-domain collective attack [Quantum~Sci.~Technol. {\bf 3}, 025007 (2018)]. It achieved this remarkable SKR by means of binary phase-shift keying (BPSK) of multiple optical modes. Moreover, it did so with available technology, and without space-division or wavelength-division multiplexing. In this paper we explore whether replacing FL-QKD's BPSK modulation with a high-order encoding can further increase that protocol's SKR. First, we show that going to $K$-ary phase-shift keying with $K = 32$ doubles---from 2.0 to 4.5\,Gbit/s---the theoretical prediction from [Phys.~Rev.~A {\bf 94}, 012322 (2016)] for FL-QKD's BPSK SKR on a 50-km-long fiber link. Second, we show that $2d\times 2d$ quadrature amplitude modulation (QAM) does not offer any SKR improvement beyond what its $d=1$ case---which is equivalent to quadrature phase-shift keying---provides.

Decoherence can help quantum cryptographic security

In quantum key distribution, one conservatively assumes that the eavesdropper Eve is restricted only by physical laws, whereas the legitimate parties, namely the sender Alice and receiver Bob, are subject to realistic constraints, such as noise due to environment-induced decoherence. In practice, Eve too may be bound by the limits imposed by noise, which can give rise to the possibility that decoherence works to the advantage of the legitimate parties. A particular scenario of this type is one where Eve can't replace the noisy communication channel with an ideal one, but her eavesdropping channel itself remains noiseless. Here, we point out such a situation, where the security of the Ping-Pong protocol (modified to a key distribution scheme) against a noise-restricted adversary improves under a non-unital noisy channel, but deteriorates under unital channels. This highlights the surprising fact that, contrary to the conventional expectation, noise can be helpful to quantum information processing. Furthermore, we point out that the measurement outcome data in the context of the non-unital channel can't be simulated by classical noise locally added by the legitimate users.

Multipartite continuous variable quantum communication with entanglement in the middle

Multipartite quantum key distribution (QKD) is crucial for quantum communicating and may link massive private information to the complex quantum network protocols. In this paper, we tackle one of the difficulties in multipartite quantum communications by designing a quantum key distribution scheme with improved secret key rates. We suggest an entanglement-based tripartite continuous variable quantum key distribution (CVQKD) scheme for quantum network, where the source in the middle generates tripartite state and distributes the modes of the state to legitimate parties, respectively. We analyze the mutual information among the distributed modes of the tripartite state of protocols involving different attack strategies of the eavesdropper in varied circumstances. Numeric simulation results show that the CVQKD system enables the generations of secret keys against optimal coherent attacks.

Parameter Estimation with Almost No Public Communication for Continuous-Variable Quantum Key Distribution.

One crucial step in any quantum key distribution (QKD) scheme is parameter estimation. In a typical QKD protocol the users have to sacrifice part of their raw data to estimate the parameters of the communication channel as, for example, the error rate. This introduces a trade-off between the secret key rate and the accuracy of parameter estimation in the finite-size regime. Here we show that continuous-variable QKD is not subject to this constraint as the whole raw keys can be used for both parameter estimation and secret key generation, without compromising the security. First, we show that this property holds for measurement-device-independent (MDI) protocols, as a consequence of the fact that in a MDI protocol the correlations between Alice and Bob are postselected by the measurement performed by an untrusted relay. This result is then extended beyond the MDI framework by exploiting the fact that MDI protocols can simulate device-dependent one-way QKD with arbitrarily high precision.

New Quantum Key Distribution Scheme Based on Random Hybrid Quantum Channel with EPR Pairs and GHZ States

A theoretical quantum key distribution scheme based on random hybrid quantum channel with EPR pairs and GHZ states is devised. In this scheme, EPR pairs and tripartite GHZ states are exploited to set up random hybrid quantum channel. Only one photon in each entangled state is necessary to run forth and back in the channel. The security of the quantum key distribution scheme is guaranteed by more than one round of eavesdropping check procedures. It is of high capacity since one particle could carry more than two bits of information via quantum dense coding.

Secure Self-healing Group Key Distribution Scheme with Constant Storage for SCADA Systems in Smart Grid

Smart grid has a great advantage over the traditional power grid and it is a critical condition in people’s daily life. The security of data communication in smart grid is important and needs to be efficiently guaranteed. The supervisory control and data acquisition (SCADA) systems is in charge of supervising the sensitive process. In SCADA systems, the secure communication between control center and remote terminal units can be achieved by the key distribution mechanism. However, the remote terminal units are resource-constrained and sometimes are not available so that they cannot receive the session key updating broadcast. Self-healing is an efficient mechanism to calculate missing session keys by using later broadcast messages. In this paper, we propose an efficient self-healing group key distribution scheme for SCADA systems. The security analysis illustrates that our scheme satisfy the basic security properties defined in security model. According to the performance evaluation from storage and communication cost viewpoints, the proposed scheme is efficient.

Secure Key Distribution Strategy in OFDM-PON by Utilizing the Redundancy of Training Symbol and Digital Chaos Technique

A secure key distribution scheme for orthogonal frequency division multiplexing (OFDM) passive optical network system is proposed and experimentally demonstrated. The training symbol (TS), which is used for time synchronization and channel estimation, is formed by adopting a noise-like chaotic sequence. The redundancy of the TS is utilized to embed secure keys. An experiment is performed, in which 7.64 Gb/s 16-quadrature-amplitude-modulation OFDM data and 28.4 Mb/s keys embedded in are successfully transmitted over 25 km standard single mode fiber. The results indicate a promising key distribution method for physical layer secure optical communication.

Proof-of-principle experimental realization of a qubit-like qudit-based quantum key distribution scheme

In comparison to qubit-based protocols, qudit-based quantum key distribution ones generally allow two cooperative parties to share unconditionally secure keys under a higher channel noise. However, it is very hard to prepare and measure the required quantum states in qudit-based protocols in general. One exception is the recently proposed highly error tolerant qudit-based protocol known as the Chau15 (Chau 2015 Phys. Rev. A 92 062324). Remarkably, the state preparation and measurement in this protocol can be done relatively easily since the required states are phase encoded almost like the diagonal basis states of a qubit. Here we report the first proof-of-principle demonstration of the Chau15 protocol. One highlight of our experiment is that its post-processing is based on practical one-way manner, while the original proposal in Chau (2015 Phys. Rev. A 92 062324) relies on complicated two-way post-processing, which is a great challenge in experiment. In addition, by manipulating time-bin qudit and measurement with a variable delay interferometer, our realization is extensible to qudit with high-dimensionality and confirms the experimental feasibility of the Chau15 protocol.

Passive measurement-device-independent quantum key distribution with orbital angular momentum and pulse position modulation

Based on the orbital angular momentum and pulse position modulation, we present a novel passive measurement-device-independent quantum key distribution (MDI-QKD) scheme with the two-mode source. Combining with the tight bounds of the yield and error rate of single-photon pairs given in our paper, we conduct performance analysis on the scheme with heralded single-photon source. The numerical simulations show that the performance of our scheme is significantly superior to the traditional MDI-QKD in the error rate, key generation rate and secure transmission distance, since the application of orbital angular momentum and pulse position modulation can exclude the basis-dependent flaw and increase the information content for each single photon. Moreover, the performance is improved with the rise of the frame length. Therefore, our scheme, without intensity modulation, avoids the source side channels and enhances the key generation rate. It has greatly utility value in the MDI-QKD setups.

Continuous‐Variable Quantum Key Distribution Scheme with Odd Coherent States

The Quantum key distribution (QKD) has been entering the practical application era. The odd coherent state which follows sub Poisson distributed has been confirmed to extend transmission distance and improve secret key rate in Discrete-variable quantum key distribution (DVQKD) protocol. We propose Entanglement-based (EB) scheme of Continuous-variable quantum key distribution (CVQKD) with odd coherent state. This scheme allows distributing Gaussian modulated CVQKD with laser light which could be odd coherent state. We analyze the logarithmic negativity between entangled odd coherent states and the security. The results show that renewed scheme can extend secure distance by 10.6% and enhance the tolerance excess noise in same parameter, and the renewed scheme could be applied to prepare-and-measure (P&M) model in CVQKD.

Delay and cost performance analysis of the diffie-hellman key exchange protocol in opportunistic mobile networks

Diffie-Hellman (DH) provides an efficient key exchange system by reducing the number of cryptographic keys distributed in the network. In this method, a node broadcasts a single public key to all nodes in the network, and in turn each peer uses this key to establish a shared secret key which then can be utilized to encrypt and decrypt traffic between the peer and the given node. In this paper, we evaluate the key transfer delay and cost performance of DH in opportunistic mobile networks, a specific scenario of MANETs where complete end-to-end paths rarely exist between sources and destinations; consequently, the end-to-end delays in these networks are much greater than typical MANETs. Simulation results, driven by a random node movement model and real human mobility traces, showed that DH outperforms a typical key distribution scheme based on the RSA algorithm in terms of key transfer delay, measured by average key convergence time; however, DH performs as well as the benchmark in terms of key transfer cost, evaluated by total key (copies) forwards.

Self-Similar key generation for secure communication in multimedia applications

Long term research activities focus on the provision of fundamental understanding and easy deployment of multimedia services on the multimedia communication. The rapid growth of digital communication and electronic data exchange provides the intensive data transfer without concentrating on the security issues. Secure communication with the minimal computational and storage overhead is the challenging task with the large size members nowadays. The Group Key Management (GKM) protocols offer numerous solutions to the security issues with an efficient interaction of group members controlling them. The groups participated in secure communication belongs to open or close scenario. The participation of registered members in close group is beneficial than the open group. With the increase in number of participants, the key size and the number of key generations will increase the computational overhead. To alleviate these issues, this paper proposes the novel self-similar key generation and distribution scheme on the basis of the Elliptic Curve Diffie Hellman (ECDH) and Chinese Reminder Theorem (CRT). The assigning permission to each node to generate their own key at the specified time by the ECDH prevents the unnecessary distribution of keys that reduces the communication overhead. Then, the application of CRT theorem reduces the mathematical burden of key generation. Finally, the integration of the Elliptic Curve Cryptography (ECC) with the above mechanisms validates the number of messages transferred among the participants in both sender and receiver side. The prior key generation using ECDH and the CRT-based self-similar key generation reduces the computational and communication overhead effectively. The comparative analysis between the proposed SSKG with the existing schemes in terms of overhead, complexity assures the effectiveness of proposed schemes in secure multicast communication.

Efficient quantum key distribution using Fibonacci-number coding with a biased basis choice

The conjugation relation between the Lucas sequence and the Fibonacci sequence leads us to devise some simple modifications which essentially increase the efficiency and the capacity of the quantum key distribution scheme proposed by Simon et al. (2013) [8]. The first major ingredient of our scheme is the sources for preparing entangled OAM states based on a Vogel spiral with the same Fibonacci numbers, which can prepare two types of entangled states. The second major ingredient is the distribution of significantly different probabilities to the entangled state photons and measurement bases during both transmission and reception, thus reducing the fraction of discarded data. The third major ingredient is that we use the close relationships among the Lucas sequence, Chebyshev maps and k-Chebyshev maps to greatly enhance the capacity of each entangled particle for key generation without the limit of spiral and OAM bandwidths. Lastly, by combining the ideas proposed by Lo et al. (2005) [9] and Xue et al. (2002) [10], we divide the accepted data into different subsets in terms of the types of measurements chosen and estimate an error rate for each subset separately to guarantee the security of our proposed scheme.

PUF-Assisted Group Key Distribution Scheme for Software-Defined Wireless Sensor Networks

In this letter, a novel group key distribution scheme based on physical unclonable functions (PUFs) is proposed for software-defined wireless sensor networks. The PUF is difficult to be cloned and predicted, remarkably enhancing physical security performance of sensor nodes. In addition, under the centralized management of software-defined networking, PUF challenge is stored in the sensor nodes to minimize communication overhead. The proposed algorithm achieves group key delivery with two-way authentication function through one communication interaction. We demonstrate the scheme can resist multiple attacks, including cloning, eavesdropping, and so on, thus effectively guaranteeing the security and efficiency of group key distribution process.

Deterministic MDI QKD with two secret bits per shared entangled pair

Although quantum key distribution schemes have been proven theoretically secure, they are based on assumptions about the devices that are not yet satisfied with today’s technology. The measurement-device-independent scheme has been proposed to shorten the gap between theory and practice by removing all detector side-channel attacks. On the other hand, two-way quantum key distribution schemes have been proposed to raise the secret key generation rate. In this paper, we propose a new quantum key distribution scheme able to achieve a relatively high secret key generation rate based on two-way quantum key distribution that also inherits the robustness of the measurement-device-independent scheme against detector side-channel attacks.

Quantum-chaotic cryptography

In this work, it is presented an optical scheme for quantum key distribution employing two synchronized optoelectronic oscillators (OEO) working in the chaotic regime. The produced key depends on the chaotic dynamic, and the synchronization between Alice’s and Bob’s OEOs uses quantum states. An attack on the synchronization signals will disturb the synchronization of the chaotic systems increasing the error rate in the final key.

Pilot-multiplexed continuous-variable quantum key distribution with a real local oscillator

We propose a pilot-multiplexed continuous-variable quantum key distribution (CVQKD) scheme based on a local local oscillator (LLO). Our scheme utilizes time-multiplexing and polarization-multiplexing techniques to dramatically isolate the quantum signal from the pilot, employs two heterodyne detectors to separately detect the signal and the pilot, and adopts a phase compensation method to almost eliminate the multifrequency phase jitter. In order to analyze the performance of our scheme, a general LLO noise model is constructed. Besides the phase noise and the modulation noise, the photon-leakage noise from the reference path and the quantization noise due to the analog-to-digital converter (ADC) are also considered, which are first analyzed in the LLO regime. Under such general noise model, our scheme has a higher key rate and longer secure distance compared with the preexisting LLO schemes. Moreover, we also conduct an experiment to verify our pilot-multiplexed scheme. Results show that it maintains a low level of the phase noise and is expected to obtain a 554-Kbps secure key rate within a 15-km distance under the finite-size effect.