Authentication of Quantum Messages

Functionality

If a person sends some information over an insecure channel (a dishonest/malicious party has access to the channel), what is the guarantee that the receiver on the other end will receive the same information as sent and not something which is modified or replaced by the dishonest party? Authentication of quantum channels/quantum states/quantum messages provides this guarantee to the users of a quantum communication line/ channel. The sender is called the suppliant (prover) and the receiver is called the authenticator. Note that, it is different from the functionality of digital signatures, a multi-party (more than two) protocol, which comes with additional properties (non-repudiation, unforgeability and transferability). Also, authenticating quantum states is possible but signing quantum states is impossible, as concluded in (1).

Tags: Two Party Protocol, Quantum Digital Signature, Quantum Functionality, Specific Task, Building Block

Protocols

• Clifford Based Quantum Authentication: requires one side to be able to prepare and measure quantum states.
• Polynomial Code based Quantum Authentication: requires one side to only prepare and send quantum states

Properties

• Any scheme which authenticates quantum messages must also encrypt them. (1)
• Protocols should be non-interactive, i.e. there should be no interaction between the parties after the message has been sent.

Further Information

1. Barnum et al (2002) First protocol on authentication of quantum messages. It is also used later for verification of quantum computation in Interactive Proofs for Quantum Computation. Protocol file for this article is given as the Polynomial Code based Quantum Authentication

contributed by Shraddha Singh