Quantum authentication with key recycling
Abstract
We show that a 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 tampering is detected. 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 nonrecycled 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 and secret key resource.
 Publication:

arXiv eprints
 Pub Date:
 October 2016
 arXiv:
 arXiv:1610.03422
 Bibcode:
 2016arXiv161003422P
 Keywords:

 Quantum Physics;
 Computer Science  Cryptography and Security;
 Computer Science  Information Theory
 EPrint:
 38+17 pages, 13 figures. v2: constructed ideal secure channel and secret key resource have been slightly redefined