Cryptology ePrint Archive: Report 2016/559
Quantum homomorphic encryption for polynomial-sized circuits
Yfke Dulek and Christian Schaffner and Florian Speelman
Abstract: We present a new scheme for quantum homomorphic encryption which is compact and allows for efficient evaluation of arbitrary polynomial-sized quantum circuits. Building on the framework of Broad- bent and Jeffery and recent results in the area of instantaneous non-local quantum computation, we show how to construct quantum gadgets that allow perfect correction of the errors which occur during the homomorphic evaluation of T gates on encrypted quantum data. Our scheme can be based on any classical (leveled) fully homomorphic encryption (FHE) scheme and requires no computational assumptions besides those already used by the classical scheme. The size of our quantum gadget depends on the space complexity of the classical decryption function - which aligns well with the current efforts to minimize the complexity of the decryption function.
Our scheme (or slight variants of it) offers a number of additional advantages such as ideal compactness, the ability to supply gadgets "on demand", circuit privacy for the evaluator against passive adversaries, and a three-round scheme for blind delegated quantum computation which puts only very limited demands on the quantum abilities of the client.
Category / Keywords: cryptographic protocols / homomorphic encryption, quantum cryptography, quantum teleportation, garden-hose model
Original Publication (with major differences): IACR-CRYPTO-2016
Date: received 2 Jun 2016
Contact author: Y M Dulek at cwi nl
Available format(s): PDF | BibTeX Citation
Version: 20160603:162107 (All versions of this report)
Short URL: ia.cr/2016/559
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