Cryptology ePrint Archive: Report 2017/119

Quantum Authentication with Key Recycling

Christopher Portmann

Abstract: We show that the family of quantum authentication protocols introduced in [Barnum et al., FOCS 2002] can be used to construct a secure quantum channel and additionally recycle all of the secret key if the message is successfully authenticated, and recycle part of the key if the message has been tampered with. We give a full security proof that constructs the secure channel given only insecure noisy channels and a shared secret key. We also prove that the number of recycled key bits is optimal for this family of protocols, i.e., there exists an adversarial strategy to obtain all non-recycled bits. Previous works recycled less key and only gave partial security proofs, since they did not consider all possible distinguishers (environments) that may be used to distinguish the real setting from the ideal secure quantum channel.

Category / Keywords: Quantum cryptography, composable security, authentication, key recycling

Original Publication (in the same form): IACR-EUROCRYPT-2017

Date: received 13 Feb 2017

Contact author: chportma at ethz ch

Available format(s): PDF | BibTeX Citation

Version: 20170216:215522 (All versions of this report)

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