The secure communication system called Quantum Key Distribution (QKD) needs improvements in long-distance implementation because energy loss and eavesdropping threats exist. The authors present the Multi-layer Proxy Encryption Scheme (MPES) which combines proxy re-encryption together with entangled quantum particles to achieve security enhancements along with distant QKD transmission capability. Quantum repeaters within the MPES model conduct multiple encryption and decryption operations which guards fiber-optic channel data transfers. The trust-based shortest path algorithm enables more efficient photon transfer which leads to decreased transmission loss and improved efficiency. The experimental data shows that key errors decreased by 62.5% while energy efficiency increased by 90.90% when implementing the MPES against standard BB84 protocol operation. Optimal conditions for photon mean free path required keeping wavelengths at 0.0051 nm and determined the most efficient photon energy span to be between 0.01 MeV. The new modeling system enhances quantum communication protection and simultaneously achieves satisfactory key transmission speeds. The conducted research shows MPES presents itself as an effective solution for quantum-secure communication at extended ranges within cloud environments.
The secure communication system called Quantum Key Distribution (QKD) needs improvements in long-distance implementation because energy loss and eavesdropping threats exist. The authors present the Multi-layer Proxy Encryption Scheme (MPES) which combines proxy re-encryption together with entangled quantum particles to achieve security enhancements along with distant QKD transmission capability. Quantum repeaters within the MPES model conduct multiple encryption and decryption operations which guards fiber-optic channel data transfers. The trust-based shortest path algorithm enables more efficient photon transfer which leads to decreased transmission loss and improved efficiency. The experimental data shows that key errors decreased by 62.5% while energy efficiency increased by 90.90% when implementing the MPES against standard BB84 protocol operation. Optimal conditions for photon mean free path required keeping wavelengths at 0.0051 nm and determined the most efficient photon energy span to be between 0.01 MeV. The new modeling system enhances quantum communication protection and simultaneously achieves satisfactory key transmission speeds. The conducted research shows MPES presents itself as an effective solution for quantum-secure communication at extended ranges within cloud environments.
Modern quantum key distribution (QKD) network designs are based on sending photons from one node to another and require free-space or dedicated fiber optic cables between nodes. The purpose of this is to co-generate secret key material on both sides of the quantum channel. In addition to this quantum link, there are several insecure classical channels that allow QKD algorithms to exchange book-keeping information and send symmetrically encrypted data. The attenuation of photons transmitted through fiber becomes too high to practically generate key material over fiber at distances of more than 100 km. Free-space transmission through the atmosphere or the vacuum of space can reduce attenuation, but at the cost of system complexity and sensitivity to other impairments, such as weather. To extend the effective range of QKD networks, we present a method that combines QKD algorithms with post-quantum, homomorphic key-switching to allow multiple parties to effectively share secret key material over longer distances through semi-trusted relay nodes. We define how such a system should work for arbitrary network topologies and provide proofs that our scheme is both correct and secure. We assess the feasibility of this solution by building and evaluating two implementations based on lattice-based cryptography: learning with errors.
Recent developments in quantum-enhanced security have demonstrated encouraging promise for enhancing cloud computing environments' security. Utilizing quantum physics, in particular Quantum Key Distribution (QKD), provides a new method for generating cryptographic keys and improves cloud data transport security. The present study offers a thorough investigation of the integration of QKD with conventional encryption techniques, including Advanced Encryption Standard (AES), in order to tackle the dynamic cyber security scenario in cloud computing. The approach entails combining AES for encryption and decryption procedures and establishing a QKD layer within the cloud architecture to produce true quantum keys utilizing Quantum in Cloud technology. Data transmission security is greatly improved by the smooth integration of AES with QKD-generated keys, guaranteeing confidentiality, integrity, and authenticity. In addition, strong key management practices are put in place to handle cryptographic keys safely at every stage of their lifespan, reducing the possibility of unwanted access or interception. The suggested approach successfully addresses the difficulties presented by cyber threats by offering a robust and flexible means of enhancing security in cloud-based systems. Using both traditional and quantum encryption methods, this strategy provides a strong barrier against cyber-attacks, data leaks, and other security flaws. After 70 simulation rounds, the suggested strategy, which is implemented using the QKD-AES framework in Python software, achieved a data access rate of 820 MB/s. In addition to providing an accurate and quantitative assessment of the performance, this also exhibits a high data access rate attained under simulated conditions. At 15 milliseconds, the key generation time was achieved with efficiency, guaranteeing the quick creation of secure cryptographic keys in cloud environments. Overall, there is a lot of potential in using quantum-enhanced security techniques to protect sensitive data and guarantee the integrity of cloud computing infrastructures.
The widespread cryptographic methods RSA and AES have become more susceptible to quantum-based attacks because researchers developed quantum algorithms such as Shor's and Grover's. QKD chromosomes from quantum mechanics grant authorized parties the ability to exchange cryptographic keys securely alongside built-in eavesdropping detection functionality. In the proposed method a Quantum Key Distribution (QKD) is used to integrate into cloud environments to secure data against quantum threats which have become crucial security concerns today. A new security framework for combining QKD with standard cloud utilities strengthens both access privacy and verify data integrity and ensure authentication of user information. The system framework consists of key generation from quantum elements followed by distribution through quantum channels to support secure communication protocols for Software as a Service (SaaS) and Platform as a Service (PaaS) as well as Infrastructure as a Service (IaaS). The key performance evaluation of the QKD system includes measurements of key generation rate together with Quantum Bit Error Rate (QBER) and eavesdropping detection accuracy rates. The analysis against traditional cryptographic systems proves that QKD stands superior in quantum attack resilience. The proposed system demonstrates its efficiency and robustness through simulation outcomes as well as visual representations. The presented work demonstrates both the revolutionary capability of quantum technology for cloud security along with a deployable system architecture for future systems implementation. The research work advances the creation of cloud infrastructure systems which combine high security resilience to protect against future cyber threats.
This paper investigates a novel approach to enhancing cryptographic key distribution using entanglement swapping. Current quantum key distribution (QKD) protocols are often limited by distance due to signal loss and decoherence during the direct transmission of entangled photons. This research proposes a protocol that overcomes these limitations by employing entanglement swapping, effectively extending the range of secure key exchange. The core of the method involves strategically swapping entangled pairs to create correlated states between distant parties, circumventing the need for direct transmission over long distances. Mathematical formulations detailing the protocol's key steps, including the quantum operations and measurement outcomes, are presented. The analysis demonstrates a pathway towards significantly increasing the practical range of QKD systems, offering a potential solution for secure communication over greater distances. The theoretical framework presented here lays the groundwork for future experimental implementations and further optimization of entanglement swapping protocols for enhanced QKD performance.
Quantum communication and information networks offer unprecedented processing efficiency and security for data transfers. Technologies like quantum key distribution (QKD), quantum repeaters, quantum memory, and quantum entanglement sources are enabling technologies that ensure secure communication. QKD methods use quantum physics concepts to establish cryptographic keys, while quantum repeaters compensate for signal loss in fiber optic cables. Quantum memory enables storage and retrieval of quantum information, while quantum entanglement generators generate entangled photon pairs. Artificial intelligence and machine learning have significantly improved the efficacy and security of quantum communication. These methods can facilitate ultra-secure, reliable, large-scale communication and even a future quantum internet by analyzing quantum protocols and mitigating noise-induced errors. QKD protocols ensure secure communication channels, while quantum repeaters establish secure long-distance communication lines by mitigating signal loss. Traditional Internet technology is susceptible to surveillance due to Shannon's information theory and mathematics. The quantum internet (QI) uses satellite-based quantum communication and quantum cryptographic protocols for physical QI. Quantum entanglement sources fortify secure communication protocols, improving resistance to attacks. Quantum information networks (QINs) enhance computing, sensing, and security capabilities over extended distances. The development of reliable, robust communication systems depends on these technologies. Quantum-secured networks enhance urban security, smart management, and infrastructure protection by providing data privacy and facilitating secure data transmission, thereby facilitating robust infrastructure and technological development.
Quantum communications enable secure key transmission and entanglement distribution, but their rates and maximum transmission distances are limited due to the losses and noise introduced by quantum channels. Various techniques have been developed to address these limitations, tailored to the platform and the nature of the decoherence. In this thesis, we explore ways to enhance the performance of quantum communications, with a particular focus on increasing the key rates and transmission distances in quantum key distribution (QKD), a method that leverages quantum mechanics to securely share keys between trusted parties. Additionally, we aim to improve the purity of entangled states shared between two parties, contributing to broader advancements in quantum communications. We begin by introducing a software-enhanced continuous-variable QKD (CV-QKD) protocol, where keys are encoded onto the phase and amplitude degrees of the optical field. This protocol enhances both transmission distance and key rates through a post-selection method employing arbitrary filters, experimentally demonstrated on two different platforms. Its adaptability makes it highly promising, as it can be implemented on existing CV-QKD platforms and dynamically optimises key rates for rapidly changing channels. We then present a protocol for the pure-loss channel leveraging quantum repeaters to mitigate the channel losses by segmenting the total communication distance into smaller, more manageable intervals. This repeater-like protocol introduces a more efficient entanglement-swapping measurement at the repeater station than the state-of-the-art twin-field protocols. Instead of polarisation encoding, our protocol relies on encoding keys in the photon-number basis, optimising the states to achieve the highest key rates for each distance. Notably, this protocol shows strong potential for improving long-distance quantum communication by surpassing the capacity of the direct communication channel at a shorter distance than the existing repeater protocols such as twin-field QKD while achieving an overall higher transmission distance. Finally, in this thesis, we demonstrate that for the Pauli-dephasing channel, placing a node in the middle of the quantum channel to perform a Bell-state measurement as an entanglement-swapping operation does not result in improved key rates, even with reduced decoherence. As a result, we propose an entanglement purification protocol that refines a larger set of noisy entangled states into a smaller set of high-fidelity ones using local operations and classical communication. This purification protocol builds upon earlier purification methods, extending their application from two Bell pairs to any number of Bell pairs and thereby achieving the capacity of the dephasing channel. Through numerous recursive iterations, it produces near-perfect Bell pairs, making it well-suited for quantum repeaters and correcting dephasing errors in quantum computers.