On quantum and approximate privacy

Abstract

This paper studies privacy and secure function evaluation in communication complexity. The focus is on quantum versions of the model and on protocols with only approximate privacy against honest players. We show that the privacy loss (the minimum divulged information) in computing a function can be decreased exponentially by using quantum protocols, while the class of privately computable functions (i.e., those with privacy loss 0) is not enlarged by quantum protocols. Quantum communication combined with small information leakage on the other hand makes certain functions computable (almost) privately which are not computable using either quantum communication without leakage or classical communication with leakage. We also give an example of an exponential reduction of the communication complexity of a function by allowing a privacy loss of $o(1)$ instead of privacy loss 0.

30 pages, appeared at 19th Symposium on Theoretical Aspects of Computer Science, STACS '02, to appear in Theory of Computing Systems

References in corpus (7)

• Strengths and Weaknesses of Quantum Computing
• Quantum Copying: Beyond the No-Cloning Theorem
• Insecurity of Quantum Secure Computations
• Quantum communication complexity of symmetric predicates
• Quantum vs. Classical Communication and Computation
• Quantum Circuits with Mixed States
• Lower bounds for quantum communication complexity

Cited by in corpus (8)

• Towards quantum-based privacy and voting
• Lower bounds on information complexity via zero-communication protocols and applications
• Interaction in Quantum Communication
• Quantum Private Information Retrieval with Sublinear Communication Complexity
• Quantifying the Leakage of Quantum Protocols for Classical Two-Party Cryptography
• Practical Quantum Appointment Scheduling
• Communication Complexity of Private Simultaneous Quantum Messages Protocols
• On the Power of Two-Party Quantum Cryptography