BITS Faculty Publications
Permanent URI for this communityhttp://localhost:4000/handle/123456789/1867
Browse
11 results
Search Results
Item PUF-AQKD: a hardware-assisted quantum key distribution protocol for man-in-the-middle attack mitigation pdf(IEEE, 2025-05) Bhatia, Ashutosh; Bitragunta, Sainath; Tiwari, KamleshThe Quantum Key Distribution (QKD) protocol utilizes quantum mechanics principles for cryptographic key exchange, ensuring absolute secrecy. Current QKD techniques are susceptible to man-in-the-middle (MITM) attacks due to the absence of an inherent mechanism for identity verification within the quantum channel. For authentication, these systems rely on classical or post-quantum cryptography, which diminishes the perfect security advantage provided by QKD. We present a Physical Unclonable Function (PUF)-based authenticated QKD protocol (PUF-AQKD), which avoids the necessity for authenticated classical channels and is useful in mitigating MITM attacks. The fundamental concept of PUF-AQKD is to implement a phase shift in the basis used for polarizing the transmitted qubits. The phase shift is dictated by PUFs, which are anticipated to result in analogous (correlated) responses for devices manufactured under similar conditions but dissimilar responses in different conditions. An adversary lacking a correlated PUF response shared by Alice and Bob would inadvertently increase the Quantum Bit Error Rates (QBER) observed at Bob’s end. We present a mathematical model to assess the efficacy of the proposed PUF-AQKD method and perform simulations utilizing the NetSquid simulator. The mathematical analysis and simulation findings indicate that PUF-AQKD can efficiently identify eavesdroppers, even during incomplete measurements, without the necessity of an authorized classical channel.Item Adaptive RIS design and optimization for cooperative ris-assisted wireless systems(IEEE, 2025-07) Bitragunta, Sainath; Bhatia, AshutoshWe propose an adaptive RIS-based cooperative transmission strategy that jointly selects one of two RIS paths and dynamically optimizes the number of active meta-atoms to maximize physical layer (PHY) secrecy capacity under a total average power constraint. Unlike existing approaches that fix the RIS size K or assume identical fading on all links, our framework uses long-term statistics to probabilistically choose between two RISs (upper or lower) with arbitrary first-hop fading, and leverages instantaneous channel state information (CSI) on the selected path to solve a convex K-sizing problem via a Lagrangian multiplier approach. We derive and present the solution for optimal K, and numerically evaluate the average PHY secrecy capacity and average PHY secrecy efficiency for the proposed optimal strategy. Numerical results show that the proposed optimal-K strategy achieves up to 35% higher average PHY secrecy capacity and 50% improvement in average PHY secrecy efficiency compared to a fixed-K benchmark strategy across moderate power thresholds. Furthermore, we present an insightful asymptotic analysis for average PHY secrecy capacity in an interesting scaling regime. Our findings demonstrate the practical benefits of adaptive RIS for cooperative PHY secure and energy-efficient beyond fifth generation (B5G) wireless systemsItem Quantum key distribution optimization: reducing communication overhead in post-processing steps(IEEE, 2025-03) Bhatia, Ashutosh; Bitragunta, Sainath; Tiwari, KamleshQuantum Key Distribution (QKD) is a ground-breaking method in modern cryptography that uses quantum mechanics to establish secure communication channels. Unlike classical cryptographic techniques, QKD provides unconditional security based on quantum principles, such as the no-cloning theorem and the uncertainty principle. However, existing QKD systems often suffer from high overhead in key post-processing, affecting efficiency and scalability, especially in resource-constrained environments such as IoT. This paper addresses these challenges by introducing two key optimizations to enhance the efficiency and security of QKD systems. First, we propose a method using Pseudorandom Number Generators (PRNGs) to determine key bit positions for verification by Alice and Bob, significantly reducing communication over-head. Second, we employ hash-based subsequence comparison to minimize data exchange and leverage the cryptographic strength of hash functions. Results demonstrate that these strategies effectively reduce key post-processing overhead and improve the efficiency of QKD systems in real-world conditions making QKD more practical and scalable for diverse application contexts.Item Efficient routing for QKD network using novel quantum optimization approach(IEEE, 2025) Bitragunta, Sainath; Bhatia, AshuthoshWith exponential growth and associated milestones set in quantum information and quantum computing (QC) technologies, QC is becoming a threat to existing key encryption strategies that leverage asymmetric cryptographic algorithms like RSA (Rivest, Shamir, Adleman) encryption. Since these algorithms form the backbone of Internet communication, it becomes essential to utilize secure quantum methods for key generation and distribution. The quantum key distribution (QKD) networks have since been extensively researched and implemented with various communication protocols, primarily utilizing the Quantum Entanglement and Quantum Key Correction paradigms. Efficient routing is one of the significant problems in classical and hybrid networks. It is important to propose novel hybrid and efficient routing protocols based on modern optimization approaches to design secure, fidelitous, and efficient quantum information networks. We perform this optimization by generating a cost function to implement quantum optimization algorithms, namely the Quantum Approximate Optimization Algorithm (QAOA). We further draw a comparison with the state-of-the-art graph theory-based optimization techniques. The primary objective of this paper is to fabricate a robust quantum communication network and to subsequently analyze the effectiveness of quantum based techniques to carry out network routing and link optimization, generating scope for the utilization of quantum architecture to enhance security in Q KD networks.Item Enhanced lightweight quantum key distribution protocol for improved efficiency and security(IEEE, 2025) Bhatia, Ashutosh; Bitragunta, Sainath; Tiwari, KamleshQuantum Key Distribution (QKD) provides secure communication by leveraging quantum mechanics, with the BB84 protocol being one of its most widely adopted implementations. However, the classical post-processing steps in BB84, such as sifting, error correction, and key verification, often result in significant communication overhead, limiting its efficiency and scalability. In this work, we propose three key optimizations for BB84: (1) PRNG-based predetermined key bit positioning, which eliminates redundant bit exchanges during sifting, (2) hash-based subsequence comparison, enabling lightweight and efficient key verification, and (3) adaptive basis reconciliation, which minimizes the communication costs associated with basis matching. The proposed optimizations achieve a 50% reduction in communication overhead for large key sizes compared to traditional QKD protocols, as demonstrated through rigorous performance analysis. While the focus of this work is on the BB84 protocol, these optimizations are also directly applicable to a broader class of Discrete-Variable QKD (DV-QKD) protocols, such as six-state, B92, and E91, which share a fundamentally similar post-processing structure. This generality highlights the modularity and adaptability of the proposed methods across diverse QKD implementations. The proposed optimizations enhance post-processing efficiency and scalability, enabling practical deployment in bandwidth-limited environments like IoT networks, secure financial systems, and defense communications, thereby supporting broader adoption of quantum communication systems.Item Quantum computing-accelerated kalman filtering for satellite clusters: algorithms and comparative analysis(IEEE, 2025-01) Bitragunta, Sainath; Bhatia, Ashutosh; Tiwari, KamleshThe increasing demand for high-precision real-time data processing in satellite clusters requires efficient algorithms to manage inherent uncertainties in space-based systems. We propose an innovative framework that integrates Quantum Neural Network (QNN) architecture into Kalman filtering processes, specifically tailored for Low Earth Orbit satellite clusters. Our quantum computing-based approach achieves a significant improvement in prediction accuracy and a reduction in mean absolute error compared to classical Kalman filtering techniques. These advances significantly improve computational efficiency and error handling, making the method highly scalable under varying noise levels. A comparative analysis demonstrates the superior performance of the Quantum Kalman Filter in processing speed, resource utilization, and prediction accuracy, all evaluated within the constraints of LEO satellite constellations. These findings highlight the potential of quantum computing to optimize data processing strategies for future missions, including deep space explorations.Item Secrecy capacity and efficiency outage analysis of cooperative phy-secure wireless systems and secrecy capacity-based RIS design(IEEE, 2025-03) Bitragunta, Sainath; Bhatia, AshutoshPhysical layer (PHY) security (PLS) leverages the inherent randomness of wireless fading channels to provide enhanced secrecy capacity. In this work, we consider a four-node, dual hop, eavesdropper-aware cooperative PHY-security model. Considering probabilistic relay selection and relaying in the presence of hybrid fading channels, we develop an insightful analysis for the probability of PHY-secrecy capacity outage (PSCO) and PHY-secrecy efficiency outage (PSEO). Specifically, we derive closed form expressions for these performance measures and evaluate them numerically to obtain valuable qualitative insights. We also develop an insightful comparative study to show that the cooperative PLS relay model having a destination node equipped with multiple antennas and performing selection combining delivers superior PHY-secrecy outage performance. We extend the analysis to the reconfigurable intelligent surface (RIS)-assisted cooperative PLS system. Specifically, we address the design problem of N, the number of reflecting elements in RIS. We develop insightful criteria based on secrecy capacity to derive a closed form lower bound on N. This insightful result provides the values of N that could achieve superior PHY-secrecy capacity than the relay-assisted cooperative PLS system. Our analysis of the former cooperative PLS model and its extension to RIS design is useful for next generation cooperative PLS relay and RIS-assisted wireless systems and networks.Item Relay Selection, Eavesdropper-Aware Relaying, PHY-Secrecy Capacity Analysis of Cooperative Wireless System over Hybrid Fading Channels(IEEE, 2023) Bhatia, Ashutosh; Bitragunta, SainathPhysical layer (PHY) security (PLS) exploits the randomness of wireless fading channels and offers better secrecy capacity. Cooperative and eavesdropper-aware relays are useful in establishing reliable and energy-efficient communication links between the source transmitter and destination receiver and enhancing PHY secrecy. We consider a four-node, two-hop cooperative PHY-security model with one eavesdropper node. For it, we propose relay selection probabilistically and relaying in the presence of hybrid fading channels. We derive closed-form expressions for probabilities with which the regenerative relay is selected. Further, we develop an analysis of PHY-secrecy capacity and gain useful insights. We evaluate and validate the performance of the proposed strategy and present different numerical results. The proposed model with the relay selection and energy-efficient relaying strategy is a useful potential benchmark for more complex power-adaptive cooperative PHY-secure systems and networks.Item Simultaneous Quantum Information and Power Transfer-Based Green QKD Receiver Architectures(IEEE, 2024) Bhatia, Ashutosh; Bitragunta, Sainath; Tiwari, KamleshConsidering the carbon footprint of rapidly evolving quantum systems and technologies, it is essential to develop energy efficient and sustainable next generation quantum communication systems. Simultaneous Lightwave Information and Power Transfer (SLIPT) enables the transfer of power and information from a transmitter to a receiver through light waves in the infrared (IR) and visible portions of the electro-magnetic spectrum. In this work, the authors propose QKD-featured, SLIPT-enabled (QuIPT) quantum communication hybrid receiver architectures. Specifically, the authors present simplified green QKD receiver architectures integrating free space QKD and SLIPT. The proposed system is useful for developing QKD-featured autonomous quantum Internet of Light Things (QIoLT). The simplified architecture comprises two key modules: the QKD-decryption and decoding module and the energy harvesting subsystem module. Finally, the authors present additional remarks on extending the architectures to include radio frequency based energy harvesting (RFbEH) modules for superior performanceItem QC-Stack: A Layered Reference Model for Quantum Computers(IEEE, 2024) Bhatia, Ashutosh; Bitragunta, Sainath; Tiwari, KamleshThis paper presents a layered architecture QC-Stack for the quantum computing domain. It is a comprehensive framework explaining quantum computing systems by identifying three fundamental layers: the physical, system, and application layers. Each plays a crucial role in implementing quantum computing systems in practice. The physical layer evaluates quantum hardware technologies based on crucial performance parameters such as qubit quality, connectivity, and scalability. The system layer, which includes quantum firmware, compilers, operating systems, and software development tools, bridges the gap between the physical and application layers. The application layer incorporates Quantum Programming Languages and algorithms, emphasizing their significance in leveraging quantum computing potential across various domains. The paper provides a comparative analysis at a higher level of existing quantum algorithms, protocols, and hardware and software technologies within each sub-layer. It also highlights the strengths and weaknesses of different technologies at each layer. This holistic model can guide researchers and practitioners, offering insights into the ever-evolving landscape of quantum technology