Quantum cryptography is a practical method of secret communication that guarantees the foolproof secrecy. This paper presents the simulation for implementation of a Quantum Key Distribution (QKD) protocol BB84, the pioneering, and most basic and fundamental protocol. We use the quantum computing platform developed by IBM named as Qiskit for the simulation of the BB84 protocol, implementing it with and without an Eve eavesdropper for studying the relative outcomes. Recently, Qiskit is globally very popular for quantum simulations because it provide us the opportunity to simulate quantum logic circuit on classical computer as well as real quantum computers owned by IBM. As per our best knowledge, there is no any proposal published for quantum circuit by anyone for BB84 QKD. We performed experimentation on local as well as cloud simulators: 1) The "qasm_simulator" was used as local machine simulator, and 2) The "ibmqx2" simulator was used as IBM cloud quantum simulator. The outcome of local as well as IBM simulator with and without an eavesdropper, between the two parties involved in key exchange were recorded and presented in the results section.
Quantum cryptography is a practical method of secret communication that guarantees the foolproof secrecy. This paper presents the simulation for implementation of a Quantum Key Distribution (QKD) protocol BB84, the pioneering, and most basic and fundamental protocol. We use the quantum computing platform developed by IBM named as Qiskit for the simulation of the BB84 protocol, implementing it with and without an Eve eavesdropper for studying the relative outcomes. Recently, Qiskit is globally very popular for quantum simulations because it provide us the opportunity to simulate quantum logic circuit on classical computer as well as real quantum computers owned by IBM. As per our best knowledge, there is no any proposal published for quantum circuit by anyone for BB84 QKD. We performed experimentation on local as well as cloud simulators: 1) The "qasm_simulator" was used as local machine simulator, and 2) The "ibmqx2" simulator was used as IBM cloud quantum simulator. The outcome of local as well as IBM simulator with and without an eavesdropper, between the two parties involved in key exchange were recorded and presented in the results section.
The rapid progress of quantum computing demands secure communication protocols which are beyond classical cryptographic techniques. This necessity of Quantum Key Distribution (QKD) is met by providing security relying on the fundamental laws of quantum mechanics. In the work presented, the BB84 protocol is implemented using Qiskit platform provided by IBM. The performance is analyzed for both the ideal channel conditions and an intercept–resend eavesdropping scenario studying its security behavior and performance. 100% key agreement is observed with a QBER of 0% for the BB84 protocol executed under the ideal condition. When an eavesdropper is introduced, the QBER increases significantly, ranging from 16% to 38%, exceeding the acceptable security threshold of 11% and resulting in complete rejection of the generated key. Performance analysis carried out for key sizes between 100 and 1000 qubits shows that the execution time follows O(n) trend growing linearly. This simulation validates the correct operation of the BB84 protocol and demonstrates a detailed performance and security analysis of a QKD system using IBM Qiskit.
Quantum cryptography is basically based on a trusted channel in communication between two parties compared to classical channel. Recently, Quantum Key Distribution (QKD has become more secure transmission method used to transmit secret key between two legitimate parties. This paper discusses the implementation of QKD protocol (BB84 protocol), which is widely used today. The implementation simulates the communication of two parties who wish to share a secret key with the existing of eavesdropper. The existing of eavesdropper is simulated with two kinds of attacks, which is use as parameter to measure the length of final key agreed by both authenticated parties at the end of the communication. This paper also discuss about future works to fully implement the shared secret key.
Due to the importance of securing electronic transactions, many cryptographic protocols have been employed, that mainly depend on distributed keys between the intended parties. In classical computers, the security of these protocols depends on the mathematical complexity of the encoding functions and on the length of the key. However, the existing classical algorithms 100% breakable with enough computational power, which can be provided by quantum machines. Moving to quantum computation, the field of security shifts into a new area of cryptographic solutions which is now the field of quantum cryptography. The era of quantum computers is at its beginning. There are few practical implementations and evaluations of quantum protocols. Therefore, the paper defines a well-known quantum key distribution protocol which is BB84 then provides a practical implementation of it on IBM QX software. The practical implementations showed that there were differences between BB84 theoretical expected results and the practical implementation results. Due to this, the paper provides a statistical analysis of the experiments by comparing the standard deviation of the results. Using the BB84 protocol the existence of a third-party eavesdropper can be detected. Thus, calculations of the probability of detecting/not detecting a third-party eavesdropping have been provided. These values are again compared to the theoretical expectation. The calculations showed that with the greater number of qubits, the percentage of detecting eavesdropper will be higher.
Quantum Key Distribution (QKD) offers a revolutionary method for secure key exchange by exploiting the principles of quantum mechanics. This paper comprehensively reviews the pioneering BB84 protocol, its experimental realization using IBM's Qiskit framework, and the underlying quantum computing concepts. We detail the methodology including qubit encoding, measurement, basis reconciliation, and key sifting, and discuss performance metrics such as the Quantum Bit Error Rate (QBER) and key generation rate. Experimental results obtained on IBM Quantum hardware are presented and analyzed, highlighting the robustness of the protocol and its security implications. The review underscores the importance of integrating QKD with future-proof encryption schemes in a quantum-enabled era.
The rapid advancement of quantum computing poses a significant threat to classical cryptographic systems that form the backbone of modern digital security.Algorithms such as RSA and ECC, which rely on the computational difficulty of integer factorization and discrete logarithm problems, become vulnerable to quantum attacks, particularly Shor's algorithm.This project presents a comprehensive Quantum Key Distribution (QKD) Simulator that implements the BB84 and E91 protocols using IBM's Qiskit quantum computing framework, providing an interactive platform for understanding, simulating, and analyzing quantum-safe key exchange mechanisms.The simulator features a full-stack architecture with a FastAPI backend powered by Python and Qiskit for quantum circuit execution, and a React 19 frontend with TypeScript for interactive visualization.The BB84 protocol implementation supports configurable qubit counts, multiple measurement bases (Z, X, and Diagonal), Eve's intercept-resend attack simulation with adjustable interception rates, and Quantum Bit Error Rate (QBER) calculation with a security threshold of 8.5%.The E91 protocol implementation uses entangled Bell state pairs with configurable measurement angles, CHSH inequality violation testing for quantum security verification, and reverse gate anti-eavesdropping mechanisms.Additionally, the system includes an AES encryption module that uses quantum-generated keys from BB84 and E91 simulations to perform AES-128, AES-192, and AES-256 encryption, with privacy amplification for keys shorter than the required length.A simulation history system with SQLite and PostgreSQL support enables experiment tracking, comparison, and analysis.The project demonstrates the practical application of quantum mechanics principles to cryptographic security and serves as an educational tool for understanding the transition from classical to quantum-safe cryptography.
Quantum cryptography is the study of delivering secret communications across a quantum channel. Recently, Quantum Key Distribution (QKD) has been recognized as the most important breakthrough in quantum cryptography. This process facilitates two distant parties to share secure communications based on physical laws. The BB84 protocol was developed in 1984 and remains the most widely used among BB92, Ekert91, COW, and SARG04 protocols. However the practical security of QKD with imperfect devices have been widely discussed, and there are many ways to guarantee that generated key by QKD still provides unconditional security. This paper proposed a novel method that allows users to communicate while generating the secure keys as well as securing the transmission without any leakage of the data. In this approach sender will never reveal her basis, hence neither the receiver nor the intruder will get knowledge of the fundamental basis.Further to detect Eve, polynomial interpolation is also used as a key verification technique. In order to fully utilize the quantum computing capabilities provided by IBM quantum computers, the protocol is executed using the Qiskit backend for 45 qubits. This article discusses a plot of % error against alpha (strength of eavesdropping). As a result, different types of noise have been included, and the success probability of the desired key bits has been determined. Furthermore, the success probability under depolarizing noise is explained for different qubit counts.Last but not least, even when the applied noise is increased to maximum capacity, a 50% probability of successful key generation is still observed in an experiment.