Editing Authentication of Quantum Messages (section)

==Functionality==
Quantum authentication allows the exchange of quantum messages between two parties over a insecure quantum channel with the guarantee that the received quantum information is the same as the initially sent quantum message. Imagine a person sends some quantum information to another person over an insecure channel, where a dishonest party has access to the channel. How can it be guaranteed that in the end the receiver has the same quantum information and not something modified or replaced by the dishonest party? Schemes for authentication of quantum channels/quantum states/quantum messages are families of keyed encoding and decoding maps that provide 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. The quantum message is encoded using a quantum error correction code. Since using only one particular quantum error correction code would enable a third party to introduce an error, which is not detectable by this particular code, it is necessary to choose a random quantum error correction code from a set of codes. <br/> <br/>Note that, it is different from the functionality of [[Quantum Digital Signature|digital signatures]], a multi-party (more than two) protocol, which comes with additional properties (non-repudiation, unforgeability and transferability). Authenticating quantum states is possible, but signing quantum states is impossible, as concluded in [[Authentication of Quantum Messages#References|(1)]]. 
Also, unlike [[Authentication of Classical Messages|classical message authentication]], quantum message authentication requires encryption. However, classical messages can be publicly readable (not encrypted) and yet authenticated.

<br/>'''Tags:''' [[:Category:Two Party Protocols|Two Party Protocol]][[Category:Two Party Protocols]], [[Quantum Digital Signature]], [[:Category:Quantum Functionality|Quantum Functionality]][[Category:Quantum Functionality]], [[:Category:Specific Task|Specific Task]][[Category:Specific Task]], [[:Category:Building Blocks|Building Block]][[Category:Building Blocks]]