[Paper Review] Quantum cryptography -- an information theoretic security

Muhammad Nadeem|arXiv (Cornell University)|Jul 28, 2015

Quantum Information and Cryptography28 references3 citations

TL;DR

This paper proposes a unified framework for quantum cryptography based on quantum non-local correlations, enabling information-theoretic security across diverse protocols. By leveraging non-local quantum resources, the framework achieves unconditional security against both quantum and classical attacks, providing secrecy, binding, input concealment, and secure information splitting without relying on computational assumptions or impossible primitives like bit commitment.

ABSTRACT

Methods of quantum mechanics promise information-theoretic security for various protocols in cryptography. However, impossibility of some cryptographic applications such as standard bit commitment, oblivious transfer, multiparty secure computations and ideal coin tossing in quantum regime leaves an obvious question on the completeness of quantum cryptography. Instead of using wide range of rules and techniques for a variety of cryptographic applications, we demonstrate here a unified structure for quantum cryptography based on quantum non-local correlations. The unified framework achieves same goals in information-theoretic way as classical cryptography does with computational hardness. To cover the broad range of cryptographic applications, we show that the framework (i) assures secrecy by providing encryption completely unintelligible to eavesdroppers, (ii) guarantees that input from distant parties is concealed unless they are willing to reveal, (iii) assures binding, (iv) allows splitting information between several parties securely and more generally, (v) evades both quantum and classical attacks from internal as well as external eavesdropping.

Motivation & Objective

• To address the incompleteness of quantum cryptography by resolving the impossibility of standard primitives like bit commitment and oblivious transfer.
• To unify diverse cryptographic applications under a single information-theoretic framework based on quantum non-locality.
• To provide security that is immune to both internal and external eavesdropping, including quantum adversaries.
• To replace computational hardness assumptions in classical cryptography with intrinsic quantum correlations.
• To ensure secrecy, binding, input concealment, and secure multiparty information splitting without relying on unproven computational assumptions.

Proposed method

• The framework is built on quantum non-local correlations, which enable secure information exchange without direct communication between parties.
• It uses entangled quantum states to create correlations that cannot be simulated by classical means, ensuring security by the no-signaling principle.
• The method ensures that any eavesdropping attempt introduces detectable disturbances due to the monogamy of entanglement and non-locality.
• It achieves input concealment by encoding inputs in non-local correlations such that they remain hidden unless parties voluntarily reveal them.
• The framework supports secure multiparty computation by distributing information across non-locally correlated subsystems, preserving secrecy until cooperation is given.
• It evades both quantum and classical attacks by relying on the foundational principles of quantum mechanics rather than computational complexity.

Experimental results

Research questions

• RQ1 Can a single quantum framework unify diverse cryptographic protocols under information-theoretic security?
• RQ2 How can quantum non-local correlations replace computational hardness in achieving secure cryptography?
• RQ3 Can the framework ensure binding and input concealment without relying on unproven assumptions?
• RQ4 Is it possible to achieve security against both internal and external eavesdroppers using only quantum non-locality?
• RQ5 How does the framework handle secure information splitting and multiparty computation?

Key findings

• The framework achieves information-theoretic security for a broad range of cryptographic applications using only quantum non-local correlations.
• It provides unconditional secrecy, ensuring that eavesdroppers gain no useful information, regardless of their computational power.
• The method guarantees that inputs remain concealed unless parties explicitly choose to reveal them, ensuring privacy.
• The framework is secure against both quantum and classical attacks, including those from internal adversaries.
• It successfully evades the impossibility of standard primitives like bit commitment and oblivious transfer by redefining security in terms of non-locality.
• The approach demonstrates that non-local quantum correlations can serve as a foundational resource for a complete and secure cryptographic framework.