A Novel Approach Based on Quantum Key Distribution Using BB84 and E91 Protocol for Resilient Encryption and Eavesdropper Detection

Quantum cryptography is anticipated to drive substantial advancements in the field of cybersecurity. The impending arrival of quantum cryptography has the potential to compromise current encryption methods, thereby possibly compromising the effectiveness of traditional key management-based security protocols. Quantum cryptography represents a burgeoning area that necessitates thorough examination and scrutiny to validate its efficacy in safeguarding data and securely distributing secret keys. One fundamental quantum key distribution protocol, BB84, encounters challenges when operating with fewer quantum bits (qubits) and bases that only support up to 8 qubits. This limitation weakens the system’s security, making brute force, intercept, and resend attacks less challenging. Consequently, this study proposes a method to enhance the security of the BB84 protocol, to reduce susceptibility to attacks and eavesdropping. The proposed improved BB84 protocol utilizes 9, 12, and 16 quantum bits along with two, and three bases to significantly bolster security, allowing authorized parties to prevent the key distribution process and eliminate the use of compromised keys. Additionally, this study has implemented the E91 quantum key distribution protocol utilizing the Entanglement Pair Generation method to produce secure keys. While the existing E91 protocol ensures security through Bell’s theorem and Bell’s inequality, it overlooks the impact of noise, leading to inaccuracies in eavesdropper detection. Hence, this study introduces an additional security measure. Whenever an eavesdropper attempts to measure the quantum state, the proposed E91 protocol collapses its state from |10⟩ to |11⟩, setting the first qubit to |1⟩ and the other qubit to |0⟩, thus providing the eavesdropper with incorrect information, accompanied by a phase angle of 15π/8. This leads to misconception and misconfiguration, preventing eavesdroppers from obtaining useful details about transferred quantum states and compromising the keys. Additionally, considering that the proposed E91 protocol relies on entangled particles and utilizes double qubit gates, which are inherently noisier than single qubit gates and susceptible to quantum decoherence, this study employs error mitigation techniques in the final measurement to predict outcomes more efficiently.