Physical implementation of oblivious transfer using optical correlated randomness.

Area of Science:

• Quantum Information Science
• Optical Physics
• Cryptography

Background:

• Oblivious transfer (OT) is a fundamental cryptographic primitive essential for secure multi-party computation.
• Implementing OT with information-theoretic security guarantees is challenging, especially over long distances.
• Existing methods often rely on complex setups or have limited key generation rates.

Purpose of the Study:

• To demonstrate a physically implemented, information-theoretically secure one-out-of-two oblivious transfer (OT) protocol.
• To leverage optical correlated randomness from semiconductor lasers for secure communication.
• To assess the feasibility of the scheme for practical, long-distance secure computation.

Main Methods:

• Utilizing semiconductor lasers driven by common random light broadcast over optical fibers to generate correlated randomness.
• Implementing a one-out-of-two oblivious transfer protocol based on the principle of bounded observability.
• Measuring the effective key generation rate of the implemented scheme.

Main Results:

• Successful physical implementation of information-theoretic secure oblivious transfer.
• Achieved a one-out-of-two oblivious transfer with an effective key generation rate of 110 kb/s.
• Demonstrated the use of optical correlated randomness for secure cryptographic tasks.

Conclusions:

• The proposed scheme offers a promising approach for information-theoretic secure oblivious transfer over long distances.
• The method is suitable for future secure computation applications, including privacy-preserving database mining, auctions, and electronic voting.
• Optical correlated randomness provides a viable resource for practical, secure cryptographic protocols.